I have a problem with my SF- 35 furnace. It starts as soon as the fuse is installed, starts the fan, sequences the ignite circuit but will not shut off by turning down thermostat, or even shutting thermostat off. Funny thing is also the Duotherm AC unit compressor always runs after The fan is shut off. Even when the Thermostat disconnected both issues occur.
A video explaining the suburban and wire hook ups.from wall to unit would be helpful. Mine came apart and now I can't figure out which wires go where? Thanks...and if there is already a video on this please send link. Thanks for your help
My name is JR this video did help my with my problem on my sf 35 thanks for your how well you do your information video. The igniter on my heater was bad on the end and tip broke off by the time I took it out. Great job keep up the good work thank you JR.
OMG !! HELLO DARIN !! MY MAN, YOU ARE A ABSOLUTE SAINT !! THRU YOUR VIDEOS, MY FURNACE IS RUNNING SO QUIETLY, THAT IT SCARES ME !!! LOL I DON'T HEAR IT RUMBLE, BIG WOOOSH WHEN IT IGNITES. I ALMOST WANTED TO MAKE A VIDEO FOR YOU, AS I RAN INTO A " ANTIVIBRATION STRAP " THAT HELPS HOLD THE MOTOR IN THE BRACKET AND NOT ENOUGH ROOM TO MOVE THE GAS LINE BACK TO BE ABLE TO EASILY REMOVE THE BURNER HEAD ASMBLY., THE ONLY OTHER THING THAT I HAVEN'T DONE IS HOOK UP A NEW DIGITAL THERMOSTAT, AS MY SETUP RUNS THRU A CONTROL SYSTEM 6.5 V THRU 2 TEMP. HEADS COMBINING THE 12.9 THAT'S ON MY SYSTEM. YOU ARE THE VERY BEST OUT THERE, AND I'VE WATCHED TONS OF VIDEOS. ALSO, THE GAL AT YOUR OFFICE IS A ANGEL, WHO GAVE ME PART NUMBERS AND RELAYED MESSAGES FROM ME TO YOU. IF YOU EVER NEED A REFERENCE, PLEASE DON'T HESITATE TO GIVE ME A CALL !! GOD BLESS YOU AND MY RV WORKS !!!
Darren, thank you for all your knowledge and advice. I have a small RV repair shop in Mt. and alot of your knowledge, tricks and tips have saved me some headaches, keep up the great work
Thank you for making such great informative videos. Couple years ago I bought my first travel trailer from a shady guy. He knew just how to hide all the problems with all the appliances. I was the perfect target for him having an excited wife looking at it with me and not knowing anything about rvs at all!!! With your videos I’ve managed to fix all my appliances except my furnace. It’s next on my list this weekend!!
Im a DIY guy on my 5r and my brothers motorhome, and occasional repairs for friends in our RV Club. These videos you provide on your channel has helped me on numerous occasions. Your vids are about the most thourough on the tube. Thanks a million !
Thanks for the info. The problem I am having is that I can run the furnace but when light are turned on everything shuts down. I put in new batteries and checked to see if I am getting 14 bolts coming into batteries and I was but voltage dropped to 11 volts on battery also unit is the in to AC 120 volts. Why am I having this problem I can run furnace or I can run lights but not both
Your vids are invaluable! I'm in the engine building biz for about 40 years, but electrical is NOT my forte, and you explain it in a way that this self-taught mechanical engineer can understand. I need to diag my own heater, and this will help tremendously. ty
Darren You Rock!!!! Thank you so so Much!!!!! We get to go to the Fisherman’s Festival in Bodega Bay, CA this weekend because YOU helped my Guy fix our heater💞💞💞thank You so much for all of your absolutely amazing guidance 🙏
Darren Thank You for this fantastic video on Furnace Theory of Operation and thorough discussion on each component's operation. These videos are informative, educational and for a DIY RV owner, You Make Me a Happy Camper!
Thanks for the info Darren. I used one of your videos last spring to diagnose the same Suburban 35 furnace in my trailer. It had occasionally not ignited when there was call for flame, eventually it wouldn't light at all. Found it was never opening the gas valve, no 12v to the valve. When I used a power probe the valve would work just fine. Being an electronics tech I thought, hey I'll just replace the relay on the board! No dice, no electronics suppliers had any stock unless a minimum order of 1000 each! It was cheaper to put in a Dinosaur Electronics board, furnace has been happy ever since. Thanks for your videos! The wife and I really need to visit PA and the Olympic Peninsula again soon. Hello from Snohomish county!
Doing an awesome job. Mechanical incline. Used this method of hearing and listening and helped myself tell my parts person what I have come up with on my demetic 13500 btu furnace an the problem uas a sticky sail switch and cleaned it, he said did that worked but did work quite well so I replace it and works fine. I followed what was said listening and smell. I did some testing of my own then called and told them what I thought it was and they helped finish the deal was definitely the sail switch. Thanks
Your timing is amazing, as I’ve come across issues in my rv I go to see what you have on UA-cam about the topic and of course you post exactly what I need around the time I need it. Always helpful and you’re much appreciated. Never hold back, thank you for your content!
Thank you for the excellent videos. I had a problem with my Suburban furnace FS35Q. A pretty new unit on a 2019 Tiffin 36LA. Hours on the unit probably less than 50. The furnace would fire, run for about 2 minutes then stop heating and then it would try the three times and then lock out. If I turned the thermostat off and then restart it would repeat the process. Using your videos I deduced it had to be the board and bought a Dinosaur from Amazon and that fixed the issue. Thanks again for the excellent job!
really enjoyed this video thank you so much for sharing this video with me . I'm trying to get my first motorhome. I've worked hard all my life and d*mn it I want the see the USA. It has taken me several years to get to this point. I told my wife that I would never leave as long as my mother was living. Well she left us close to a year ago. We sold the family farm and now getting our house it top shape to be able to rent it out. My wife and I agree we never want to be with out a home. If we do this for 4 to 5 years and do not wish to live this life anymore then we still have our house a home to go back to. I just do not want to have to call a service person every time we have a problem. Also if I do decide to call a service person because I just do not want to fix it. At least I will have some Ideal by the sound it is making and yes I will break out my fluke it he comes up with some bull shit of a cost and prove to him what the problem is. I'm 66 years old and not stupid so do not treat me that way. I do not mind paying a person for his time to honestly repair my motorhome. Any body that does this for a living deserves to be paid for his training and knowledge. So getting back the subject thank you so much from my wife and I ! ! ! ! ! ! ! ! ! ! ! !
I haven't seen the comment yet, but it would be nice to see the video talking about the capping of the other blue wire. My understanding from school was that all furnaces had the 2 blue wires no matter the AC unit. please explain thank you!
Awesome video!! Please do a similar video for AC problems. Your videos are the best I’ve found. I’m a DIYer and trying to teach myself how to maintain my new RV
I just found your site and started watching you for about the last month. These videos are great. You have a knack for demonstrating and then fixing these problems. While traveling to Tennessee last year, we suffered a total loss of 12v power sometime in the last 3 hours of our trip. I tried to fix it my self. I just couldn't quite put all of the pieces together. I found a great repair shop in Lebanon Tn. just east of Nashville. Greg not only took the time to fix me up, he taught me a great lesson while doing it. I am hooked on learning this stuff. I plan to take some courses late this year in Athens, Texas. Now that I'm retired from Ma Bell, I am seriously considering becoming a traveling repair tech part-time. I love your content. Thank you so much. Maybe some tips and pointers about being a traveling tech?
My favorite is listening to them and knowing exactly what is wrong without even looking. I take them and bench test them most the time. Im down in sw washington Darren if you ever need a tech in the area to support any customers of yours
I saw a youtuber couple, "Called To Wander", that are having problems with their fridge. I pointed them to your 21 video fridge playlist and suggested that maybe you guys could do a collaboration video if they can't get it working (they could post, you could download and repost with your commentary).
Troubleshooting always keeps you fresh and on your toes !! RV Tech my 2nd career also 35 years HD Mechanic , Truck Trailer , Automotive , Been RV ing 5 years & decided to try RV Tech Your videos are great Alberta Canada ☮
Great videos. Very helpful - thank you. It got a rodent in it and destroyed the large fan. I removed some blades to balance it out and reinstalled, then ran the furnace until I received the new fan. Furnace was firing fine. Received new fan and installed, now it won’t fire. I now have the furnace on my bench to troubleshoot. Sail switch and high temp switch are good. I’m getting 12VDC on the red wire at the white connector on the control board. Fan is running, but gas valve never comes in - brown wire never gets 12VDC. Tested gas valve with another 12VDC source and it opens as it should - tested with air through it - all good. Electrode is tight. Is the most likely culprit the control board or the electrode? Any insight is helpful. Thanks!
I work for a rv dealership and we had one that had a bad gas valve and after replacing that it ran but not well We had 3 different guys looking at it and we were starting to think maybe it was the regulator on our test tank because it was acting like it was starving for fuel. Long story short when the original tech put the gas valve in he torqued the valve ever so slightly into the burner. And he found a service bulletin about that. Took a little twisting to tweak the line and ran flawlessly But to just look at it you would never think it was not assembled correctly And always ask if they tried to fix it themselves. Had a customer put the thermostat wires back wrong So the complaint about the furnace had me originally order a new thermostat. We get .2 in diag time from warranty that’s 12 minutes So when it takes 20 minutes to get units switched and then have to go find the customer keys to open dead bolt when only the handle is supposed to be be locked so we can access with masters Another long story short. Thermostat looked like it was working but had no signal to furnace when on heat(quick jab with multi meter) Supply chain being what it is 2 weeks later thermostat arrives. Wire in like it was and same result. Start looking at my wires and it made no sense. They had power and ground hooked up wrong but the electronic thermostat still lit up and cycled through settings. Thermostat wire was shorted was original issue. But trying to figure out which wire is which by sound ( Ac, fan high fan low heat pump and furnace) added on by diy gone wrong So you diyers if you have a warranty issue. Please don’t make it worse and then not tell you touched
Hi Justin, that will be available soon on the website (www.t3interface.com). Feel free to submit a request on the website to be notified when it is available. Thank you for your interest!
Hi Scott, this may be a video we do in the future. You will want to consider your area and what repairs are most common. For example, in our area, we don't get a lot of A/C calls, so we don't stock a lot of A/C parts. You will also want to consider the cost of the item, and may want to have parts over a certain amount be "special order".
Darren, I've been watching your videos for over a year now. I have the vast majority of them bookmarked, and whenever I have an issue of any sort, my first thought is, does Darren have a video on it. You have helped me immeasurably, and I try to pass it along whenever I can as well as spread the word about your channel. I've also purchased tools through your site and am going to check out your wiring kit you show in this video. THANKS!
Thank so much. I’m looking for someone like you in the Phoenix area to help me with a possible propane leak on my 2015 Forester MBS class C RV. Any recommendations?
I've serviced residential furnaces, boilers and AC for over 30 years. One thing I'm curious about is proving flame on an RV furnace. On a residential gas furnace flame is usually proved thru flame rectification. A small AC signal is sent thru a flame rod or sometimes the HSI. The signal is rectified as it passes thru the flame and the control is looking for DC milliamps. Since the voltage to the furnace is already DC is the control simply looking for DC milliamps to prove flame? It's somewhat amusing to have someone post a complaint that their furnace isn't running what could be wrong. It's always the sail switch. You're doing yeoman's work explaining the sequence of operation. As you said the clicks and ticks give you a lot of information once you know how the unit is supposed to operate. Thank you.
If you remove the leads from the high temperature limit switch and put them on a fuse to short around the switch you can monitor as needed to see if your symptoms change. If yes the switch is bad, if no keep swinging.
If you have a meter, you can put one lead on each side of the limit switch leaving the existing wires in place. If there's power to the switch and it's closed, you won't see voltage on the meter. If you see voltage the switch is open.
I do heating and ac . I took my furnace out one winter .found my board to be bad . I installed a new electrode . Found after I got the new board in I was tick tick tick it lit . Then took the burner apart found a-fits bugs . Also found electrode was dirty and was greater than a eighth inch so I put a new one in and tightened the gap . Now I don't hear it tick like before . Now my gas valve is clicking load .
Really enjoy your videos keep them coming. I have one question. You talk about the lead kit that you build and sell. I looked at the link in your description and can only locate the amazon list of your tools and they seem to be Fluke accessories listed. I also am addicted too tools and would be interested in seeing what comes in your kit. Making them in a kit seams much better than buying them all individually. I may just be overlooking the obvious in your list but could you help an old man out and direct me to your kit please. Thanks again.
Hi, and thanks for your interest! That tool will be available on our website, www.t3interface.com. Barring any unexpected delays, we expect to have the AquaHot Diagnostic Switch, Test Lead Set, & LP Tap Jig available in February!
Dose not seam that I'm getting 12v power to my gas solenoids everything is coming on but the gas solenoids I hear the igniter ticking but no click to the gas solenoids. But did the drill battery test and that worked. gas smell n clicking fine I'm plugged in the land /shore power no battery power.
On some of those Atwoods, the solenoid circuit passes through an on-off/reset switch, verify you're getting 12 volts coming out of the brown wire on the control board and follow it all the way to the solenoids. If you don't have 12 volts coming out of the control board then the issue may be the control board.
Hi there! You can find them on our website (www.t3interface.com) in the very near future. Feel free to sign up on our website to be notified when they are available. Thanks for your interest!
Here's a weird one! I just changed the electrode on my furnace a week or so ago and ever since then I now hear relays and switches clicking up in my cupboard that I never used to hear before. Before, the thermostat would click and immediately after the furnace would click and you'd hear the flame start. Now I hear clicks coming from way up in my cupboard that were simply never there before. I haven't taken the panel off to see what it is just yet. It's up in there where the factory router and all that is for the Lippert one control system. I have the fuses removed from that system so I know that they are not even on, but what on Earth is this clicking that I'm hearing? And why didn't I hear it before I changed the electrode? Very strange
Just watched your video. My rv furnace does everything you just explained along with a weird smell not sure if it's gas or what it's strong gives me a headache
Process of elimination. 80% of all rv issues are electrical. Intermittent issues are likely a bad connection, electrical short, or something overheating causing a fault. The other cause can also be unstable power supply. The first thing i always do is test the DC supply. It needs to ne stable. I stress the dc draw to confirm a stable supply. Then i begin testing parts for proper resistance and inspecting wires for insulation integrity. I use my digital laser thermometer to test wire and other temps. Eventually you will isolate the issue. Always consider that a hidden wire inside a wall or something that jas ahorted or disconnected. I this case i run a new wiring harness for that appliance to the source. I thwn properly label that harness from the source to the appliance.
Thank you for explaining all that but the issue I'm having with mines. I left a comment on one of your other videos. So the issue I'm having. I hear the click click click after the 15 seconds. Im not getting the one click to open the gas valve so what I did was the 12 V set up the check and see if the solenoids was good.heard the click and smell the gas. But wen I plug in to Rv not getting the click or gas. Please advise. Thanks. 8535 III Atwood
Hi, Thanks for sharing this information. I have a question as to why my Atwood MPD 38477 /8500IV is underperforming. The motor RPMs sound fine, the flame is full bore but the air out of all the floor registers is very weak. It simply has no volume. At this minute it's 39 degrees outside. I just probed the registers with my laser gun and found the outlets are 77 degrees at best. most are less than that. I checked for restrictions and found none. Any idea what I may check next? Thanks, and cheers from Louisiana.
If the outside exhaust is hot then we can assume furnace is doing it's job correctly at that point... How about the supply air from the living side feeding the furnace (and returning to living side)? Make sure the furnace is not drawing in cold air somehow and returning it to the living area. Also check the ductwork for any breaches. PS: Darren grew up in Covington!
My sail switch is clean and working properly. However my fan starts to run for about 2 seconds then shuts off for 2 seconds then runs for 2 seconds and shuts off for 2 seconds. Cage is spinning very slowly. Any thoughts.
My 1998 Fleetwood bounder,propane heat only blows in the bathroom and bedroom,but at the entry and passageways it blows cold.so only 2 vents blows hot air ,the front roof ac don't work but the lights come on for the heater ,for the front ac I think the fan is bad
Hi Rick, the test leads that Darren mentions in the video will be available on our website (www.t3interface.com) in the very near future. Feel free to sign up on the website to be notified when they are available. Thanks for your interest!
I had to replace my thermostat on Atwood 7920-ii bc I accidentally melted it with a buddy heater. Now furnace turns on for about tens seconds and the blower is barely pushing then trips 5-amp fuse on the furnace. Any suggestions on how where to look?
I have a new grand design rv and the furnace, dometic, fires up when the thermostate calls for heat. Blower turns on, ignites for 10 seconds, flame goes off, waits 20 seconds, then ignites again and runs for about 1 minute 30 seconds, then flame out, blower runs for a bit then off. Same cycle whenever there is a call for heat. Any thoughts?
Hi Justin, you can sign up to be notified when the tools are available on our website, or just send us an email at info@t3interface.com. Barring any unexpected delays, we expect to have the AquaHot Diagnostic Switch, Test Lead Set, & LP Tap Jig available in February!
@@MyRVWorks thank you. I found the sign up. Appreciate it. Found your page a few days ago. I am signed up to go to NRVTA in a few months. Been RVing for 10 years and I’m tired of working construction.
My furnace runs on shore power but when on Battery it does the same thing this one does. Fan, ignite , burn out. Repeat. Plug it into shore power and there is no issue. What up with that?
The outside temperature is more a function of how I work - LOL. It was cold this day so I brought the furnace into my our service trailer to work on it. Sorry if that was confusing...
My surburban furnace lights heats up then kicks off on the first use. Then, furnace tries to light 3 times will not light and locks out. You hear it clicking and lighting but flame goes out after a second or so. Anyone have a clue?
The first thing the furnace will do is a pre-Purge of about 15 to 30 seconds. Then it will try to ignite. After ignition it will do a post Purge for about 90 seconds. So my question, do you actually hear the furnace igniting and running or do you just hear the fan running? If you get ignition but the ignition extinguishes within a couple seconds, that is an indication that your DSI board is not detecting the flame. It could be low LP pressure, the gap of the electrode to the burner head, the igniter electrode itself, or the board. If you look at our video playlist we do have quite a few videos that cover every one of these topics. Good luck and try to stay warm.
Thank you! I understood well.. I’m fixing mine and the intermittent problems are the headache, I haven’t worked on furnaces much , also I worked for an rv guy ,. I’ve done all diagnostics on my own, without making phone calls. And it’s in isolation to the motherboard or the igniter for mine. But I am ruling the motherboard. Because my furnace shuts down. It’s different when you can grab the parts out of the service truck. L O L, And why I think it’s my motherboard is because the motherboard gets warm and then the problem acts up
Actually it was 6 minutes but after that what a wealth of information. I've learned more about my furnace from this video then all of UA-cam combined thank you for such an in-depth tutorial
You seem like you can do better. I say this because you are only adding negativity. No positivity. I would be very interested to see your video on furnace troubleshooting. Please let me know when it is completed. Remember to keep it brief and focused. Thank you.
"If you're supporting us" Every viewer (Not just patreon) is supporting just by watching your videos. Aren't these videos monetized? That's a pretty poor choice of words and will turn off many viewers.
Thanks for watching! We appreciate your viewership and hope this video was helpful to you. Stay tuned for Part 2!
I have a problem with my SF- 35 furnace. It starts as soon as the fuse is installed, starts the fan, sequences the ignite circuit but will not shut off by turning down thermostat, or even shutting thermostat off. Funny thing is also the Duotherm AC unit compressor always runs after The fan is shut off. Even when the Thermostat disconnected both issues occur.
@@thekiltedkamper2855
@@frankschauer7828 it ended up being the Dometic control board in the AC unit.
A video explaining the suburban and wire hook ups.from wall to unit would be helpful. Mine came apart and now I can't figure out which wires go where?
Thanks...and if there is already a video on this please send link. Thanks for your help
This is why I call you the RV professor!
Thank you for you’re time to explain all that stuff
It's hard to do such a complete walk through...thanks for the complete picture!
My name is JR this video did help my with my problem on my sf 35 thanks for your how well you do your information video. The igniter on my heater was bad on the end and tip broke off by the time I took it out. Great job keep up the good work thank you JR.
Great video!!
You are an AWESOME TEACHER!!
Thank you!!
OMG !! HELLO DARIN !! MY MAN, YOU ARE A ABSOLUTE SAINT !! THRU YOUR VIDEOS, MY FURNACE IS RUNNING SO QUIETLY, THAT IT SCARES ME !!! LOL I DON'T HEAR IT RUMBLE, BIG WOOOSH WHEN IT IGNITES. I ALMOST WANTED TO MAKE A VIDEO FOR YOU, AS I RAN INTO A " ANTIVIBRATION STRAP " THAT HELPS HOLD THE MOTOR IN THE BRACKET AND NOT ENOUGH ROOM TO MOVE THE GAS LINE BACK TO BE ABLE TO EASILY REMOVE THE BURNER HEAD ASMBLY., THE ONLY OTHER THING THAT I HAVEN'T DONE IS HOOK UP A NEW DIGITAL THERMOSTAT, AS MY SETUP RUNS THRU A CONTROL SYSTEM 6.5 V THRU 2 TEMP. HEADS COMBINING THE 12.9 THAT'S ON MY SYSTEM. YOU ARE THE VERY BEST OUT THERE, AND I'VE WATCHED TONS OF VIDEOS. ALSO, THE GAL AT YOUR OFFICE IS A ANGEL, WHO GAVE ME PART NUMBERS AND RELAYED MESSAGES FROM ME TO YOU.
IF YOU EVER NEED A REFERENCE,
PLEASE DON'T HESITATE TO GIVE ME A CALL !! GOD BLESS YOU AND
MY RV WORKS !!!
Thanks, George!
Darren, thank you for all your knowledge and advice. I have a small RV repair shop in Mt. and alot of your knowledge, tricks and tips have saved me some headaches, keep up the great work
Thank you Darren. Another fantastic video!
Thank you for making such great informative videos. Couple years ago I bought my first travel trailer from a shady guy. He knew just how to hide all the problems with all the appliances. I was the perfect target for him having an excited wife looking at it with me and not knowing anything about rvs at all!!! With your videos I’ve managed to fix all my appliances except my furnace. It’s next on my list this weekend!!
Im a DIY guy on my 5r and my brothers motorhome, and occasional repairs for friends in our RV Club. These videos you provide on your channel has helped me on numerous occasions. Your vids are about the most thourough on the tube. Thanks a million !
Thanks, Walter!
Thanks for the info. The problem I am having is that I can run the furnace but when light are turned on everything shuts down. I put in new batteries and checked to see if I am getting 14 bolts coming into batteries and I was but voltage dropped to 11 volts on battery also unit is the in to AC 120 volts. Why am I having this problem I can run furnace or I can run lights but not both
Volts not bolts sorry
i am smittimg with your videos...
can stop watching, can't get enough of them ....🤩
Great Job, thanks for all your help.
Your vids are invaluable! I'm in the engine building biz for about 40 years, but electrical is NOT my forte, and you explain it in a way that this self-taught mechanical engineer can understand. I need to diag my own heater, and this will help tremendously. ty
Darren You Rock!!!! Thank you so so Much!!!!! We get to go to the Fisherman’s Festival in Bodega Bay, CA this weekend because YOU helped my Guy fix our heater💞💞💞thank You so much for all of your absolutely amazing guidance 🙏
Great job as usual. Thank you
Darren Thank You for this fantastic video on Furnace Theory of Operation and thorough discussion on each component's operation. These videos are informative, educational and for a DIY RV owner, You Make Me a Happy Camper!
Thanks for the info Darren. I used one of your videos last spring to diagnose the same Suburban 35 furnace in my trailer. It had occasionally not ignited when there was call for flame, eventually it wouldn't light at all. Found it was never opening the gas valve, no 12v to the valve. When I used a power probe the valve would work just fine. Being an electronics tech I thought, hey I'll just replace the relay on the board! No dice, no electronics suppliers had any stock unless a minimum order of 1000 each! It was cheaper to put in a Dinosaur Electronics board, furnace has been happy ever since. Thanks for your videos! The wife and I really need to visit PA and the Olympic Peninsula again soon. Hello from Snohomish county!
Doing an awesome job. Mechanical incline. Used this method of hearing and listening and helped myself tell my parts person what I have come up with on my demetic 13500 btu furnace an the problem uas a sticky sail switch and cleaned it, he said did that worked but did work quite well so I replace it and works fine. I followed what was said listening and smell. I did some testing of my own then called and told them what I thought it was and they helped finish the deal was definitely the sail switch. Thanks
Your teaching skills are great marine, keep it up and Semper Fi
Your timing is amazing, as I’ve come across issues in my rv I go to see what you have on UA-cam about the topic and of course you post exactly what I need around the time I need it. Always helpful and you’re much appreciated. Never hold back, thank you for your content!
We appreciate you so much. Thank you!
Thanks, Rick!
Very helpful 👌
Thanks so much your testing sequence helped a lot my problem was fan switch plugged orfface rust )
Glad it helped
So exceptionally helpful, thank you!!
Thank you for the excellent videos. I had a problem with my Suburban furnace FS35Q. A pretty new unit on a 2019 Tiffin 36LA. Hours on the unit probably less than 50. The furnace would fire, run for about 2 minutes then stop heating and then it would try the three times and then lock out. If I turned the thermostat off and then restart it would repeat the process. Using your videos I deduced it had to be the board and bought a Dinosaur from Amazon and that fixed the issue. Thanks again for the excellent job!
Video well done. Thank you for taking the time do go over this.
really enjoyed this video thank you so much for sharing this video with me . I'm trying to get my first
motorhome. I've worked hard all my life and d*mn it I want the see the USA. It has taken me several years
to get to this point. I told my wife that I would never leave as long as my mother was living. Well she left us
close to a year ago. We sold the family farm and now getting our house it top shape to be able to rent it out.
My wife and I agree we never want to be with out a home. If we do this for 4 to 5 years and do not wish to live
this life anymore then we still have our house a home to go back to. I just do not want to have to call a service person
every time we have a problem. Also if I do decide to call a service person because I just do not want to fix it. At least
I will have some Ideal by the sound it is making and yes I will break out my fluke it he comes up with some bull shit of
a cost and prove to him what the problem is. I'm 66 years old and not stupid so do not treat me that way. I do not mind
paying a person for his time to honestly repair my motorhome. Any body that does this for a living deserves to be paid
for his training and knowledge. So getting back the subject thank you so much from my wife and I ! ! ! ! ! ! ! ! ! ! ! !
Hi Jeff, thanks for watching the video and we hope you and your wife enjoy your travels!
I haven't seen the comment yet, but it would be nice to see the video talking about the capping of the other blue wire. My understanding from school was that all furnaces had the 2 blue wires no matter the AC unit. please explain thank you!
Your videos are AMAZING!! Thank you so much for everything that you do!! We all really really appreciate your time and your knowledge!! Keep it up!!
Awesome video!! Please do a similar video for AC problems. Your videos are the best I’ve found. I’m a DIYer and trying to teach myself how to maintain my new RV
Brilliant! The way you explain things just makes sense. Great teacher! Can't wait to learn more!
I just found your site and started watching you for about the last month. These videos are great. You have a knack for demonstrating and then fixing these problems. While traveling to Tennessee last year, we suffered a total loss of 12v power sometime in the last 3 hours of our trip. I tried to fix it my
self. I just couldn't quite put all of the pieces together. I found a great repair shop in Lebanon Tn. just east of Nashville. Greg not only took the time to fix me up, he taught me a great lesson while doing it. I am hooked on learning this stuff. I plan to take some courses late this year in Athens, Texas. Now that I'm retired from Ma Bell, I am seriously considering becoming a traveling repair tech part-time. I love your content. Thank you so much. Maybe some tips and pointers about being a traveling tech?
I never understood why the one blue wire was caped off on some units. Now I know it’s a giveaway for what ac unit/ thermostat they have. 👍
My favorite is listening to them and knowing exactly what is wrong without even looking. I take them and bench test them most the time. Im down in sw washington Darren if you ever need a tech in the area to support any customers of yours
Thanks, let us know your website and perhaps we can refer people to you!
I saw a youtuber couple, "Called To Wander", that are having problems with their fridge. I pointed them to your 21 video fridge playlist and suggested that maybe you guys could do a collaboration video if they can't get it working (they could post, you could download and repost with your commentary).
Thank you!
Troubleshooting always keeps you fresh and on your toes !!
RV Tech my 2nd career also
35 years HD Mechanic , Truck Trailer , Automotive ,
Been RV ing 5 years & decided to try RV Tech
Your videos are great
Alberta Canada ☮
Great videos. Very helpful - thank you. It got a rodent in it and destroyed the large fan. I removed some blades to balance it out and reinstalled, then ran the furnace until I received the new fan. Furnace was firing fine. Received new fan and installed, now it won’t fire. I now have the furnace on my bench to troubleshoot. Sail switch and high temp switch are good. I’m getting 12VDC on the red wire at the white connector on the control board. Fan is running, but gas valve never comes in - brown wire never gets 12VDC. Tested gas valve with another 12VDC source and it opens as it should - tested with air through it - all good. Electrode is tight. Is the most likely culprit the control board or the electrode? Any insight is helpful. Thanks!
I work for a rv dealership and we had one that had a bad gas valve and after replacing that it ran but not well We had 3 different guys looking at it and we were starting to think maybe it was the regulator on our test tank because it was acting like it was starving for fuel.
Long story short when the original tech put the gas valve in he torqued the valve ever so slightly into the burner. And he found a service bulletin about that. Took a little twisting to tweak the line and ran flawlessly But to just look at it you would never think it was not assembled correctly
And always ask if they tried to fix it themselves. Had a customer put the thermostat wires back wrong So the complaint about the furnace had me originally order a new thermostat. We get .2 in diag time from warranty that’s 12 minutes So when it takes 20 minutes to get units switched and then have to go find the customer keys to open dead bolt when only the handle is supposed to be be locked so we can access with masters Another long story short. Thermostat looked like it was working but had no signal to furnace when on heat(quick jab with multi meter) Supply chain being what it is 2 weeks later thermostat arrives. Wire in like it was and same result. Start looking at my wires and it made no sense. They had power and ground hooked up wrong but the electronic thermostat still lit up and cycled through settings. Thermostat wire was shorted was original issue. But trying to figure out which wire is which by sound ( Ac, fan high fan low heat pump and furnace) added on by diy gone wrong
So you diyers if you have a warranty issue. Please don’t make it worse and then not tell you touched
I couldn't find the link below to find where to purchase the test lead kit that you we're referring too? It's not on t3.
Hi Justin, that will be available soon on the website (www.t3interface.com). Feel free to submit a request on the website to be notified when it is available. Thank you for your interest!
Excellent videos Darren! Love your detailed explanations, Thank you!
Great information. After you mentioned parts stock in your video. I was curious what common parts stock a person starting in RV repair should carry.
Hi Scott, this may be a video we do in the future. You will want to consider your area and what repairs are most common. For example, in our area, we don't get a lot of A/C calls, so we don't stock a lot of A/C parts. You will also want to consider the cost of the item, and may want to have parts over a certain amount be "special order".
Darren, I've been watching your videos for over a year now. I have the vast majority of them bookmarked, and whenever I have an issue of any sort, my first thought is, does Darren have a video on it. You have helped me immeasurably, and I try to pass it along whenever I can as well as spread the word about your channel. I've also purchased tools through your site and am going to check out your wiring kit you show in this video. THANKS!
Thank so much. I’m looking for someone like you in the Phoenix area to help me with a possible propane leak on my 2015 Forester MBS class C RV. Any recommendations?
I've serviced residential furnaces, boilers and AC for over 30 years. One thing I'm curious about is proving flame on an RV furnace. On a residential gas furnace flame is usually proved thru flame rectification. A small AC signal is sent thru a flame rod or sometimes the HSI. The signal is rectified as it passes thru the flame and the control is looking for DC milliamps. Since the voltage to the furnace is already DC is the control simply looking for DC milliamps to prove flame?
It's somewhat amusing to have someone post a complaint that their furnace isn't running what could be wrong. It's always the sail switch. You're doing yeoman's work explaining the sequence of operation. As you said the clicks and ticks give you a lot of information once you know how the unit is supposed to operate. Thank you.
If you remove the leads from the high temperature limit switch and put them on a fuse to short around the switch you can monitor as needed to see if your symptoms change. If yes the switch is bad, if no keep swinging.
If you have a meter, you can put one lead on each side of the limit switch leaving the existing wires in place. If there's power to the switch and it's closed, you won't see voltage on the meter. If you see voltage the switch is open.
I do heating and ac . I took my furnace out one winter .found my board to be bad . I installed a new electrode . Found after I got the new board in I was tick tick tick it lit . Then took the burner apart found a-fits bugs . Also found electrode was dirty and was greater than a eighth inch so I put a new one in and tightened the gap . Now I don't hear it tick like before . Now my gas valve is clicking load .
I loved the video!
Great teacher. thankyou!
Really enjoy your videos keep them coming. I have one question. You talk about the lead kit that you build and sell. I looked at the link in your description and can only locate the amazon list of your tools and they seem to be Fluke accessories listed. I also am addicted too tools and would be interested in seeing what comes in your kit. Making them in a kit seams much better than buying them all individually. I may just be overlooking the obvious in your list but could you help an old man out and direct me to your kit please. Thanks again.
Hi, and thanks for your interest! That tool will be available on our website, www.t3interface.com. Barring any unexpected delays, we expect to have the AquaHot Diagnostic Switch, Test Lead Set, & LP Tap Jig available in February!
Dose not seam that I'm getting 12v power to my gas solenoids everything is coming on but the gas solenoids
I hear the igniter ticking but no click to the gas solenoids. But did the drill battery test and that worked. gas smell n clicking fine
I'm plugged in the land /shore power no battery power.
On some of those Atwoods, the solenoid circuit passes through an on-off/reset switch, verify you're getting 12 volts coming out of the brown wire on the control board and follow it all the way to the solenoids. If you don't have 12 volts coming out of the control board then the issue may be the control board.
Thank you for your time making this video. I now understand the workings of a furnace.
Glad to help
Bye the way your the best on you tube
Excellent video. The detail and deep dive nature is great
Lots of great info,,,thanks
Enjoy your shows! Really helped me understand how the furnace works!! Thanks! How can I acquire one of your test lead sets?
Hi there! You can find them on our website (www.t3interface.com) in the very near future. Feel free to sign up on our website to be notified when they are available. Thanks for your interest!
Here's a weird one! I just changed the electrode on my furnace a week or so ago and ever since then I now hear relays and switches clicking up in my cupboard that I never used to hear before. Before, the thermostat would click and immediately after the furnace would click and you'd hear the flame start. Now I hear clicks coming from way up in my cupboard that were simply never there before. I haven't taken the panel off to see what it is just yet. It's up in there where the factory router and all that is for the Lippert one control system. I have the fuses removed from that system so I know that they are not even on, but what on Earth is this clicking that I'm hearing? And why didn't I hear it before I changed the electrode? Very strange
What have you seen with the new Furrion furnace? Have you had to resolve any issues with the wall thermometer and the temp sensor?
Do you prefer dinosaur control boards or manufacture?
Anybody can turn wrenches. Proper troubleshooting is where it's at.
Just watched your video. My rv furnace does everything you just explained along with a weird smell not sure if it's gas or what it's strong gives me a headache
Process of elimination. 80% of all rv issues are electrical. Intermittent issues are likely a bad connection, electrical short, or something overheating causing a fault. The other cause can also be unstable power supply. The first thing i always do is test the DC supply. It needs to ne stable. I stress the dc draw to confirm a stable supply. Then i begin testing parts for proper resistance and inspecting wires for insulation integrity. I use my digital laser thermometer to test wire and other temps. Eventually you will isolate the issue. Always consider that a hidden wire inside a wall or something that jas ahorted or disconnected. I this case i run a new wiring harness for that appliance to the source. I thwn properly label that harness from the source to the appliance.
Thank you
Thank you for explaining all that but the issue I'm having with mines. I left a comment on one of your other videos.
So the issue I'm having. I hear the click click click after the 15 seconds. Im not getting the one click to open the gas valve so what I did was the 12 V set up the check and see if the solenoids was good.heard the click and smell the gas. But wen I plug in to Rv not getting the click or gas. Please advise. Thanks.
8535 III Atwood
Thanks!
Hi, Thanks for sharing this information. I have a question as to why my Atwood MPD 38477 /8500IV is underperforming. The motor RPMs sound fine, the flame is full bore but the air out of all the floor registers is very weak. It simply has no volume. At this minute it's 39 degrees outside. I just probed the registers with my laser gun and found the outlets are 77 degrees at best. most are less than that. I checked for restrictions and found none. Any idea what I may check next?
Thanks, and cheers from Louisiana.
If the outside exhaust is hot then we can assume furnace is doing it's job correctly at that point... How about the supply air from the living side feeding the furnace (and returning to living side)? Make sure the furnace is not drawing in cold air somehow and returning it to the living area. Also check the ductwork for any breaches. PS: Darren grew up in Covington!
My sail switch is clean and working properly. However my fan starts to run for about 2 seconds then shuts off for 2 seconds then runs for 2 seconds and shuts off for 2 seconds. Cage is spinning very slowly. Any thoughts.
I have a hr neptune with atwood furnace, just wondered does this system have a relay ?
My 1998 Fleetwood bounder,propane heat only blows in the bathroom and bedroom,but at the entry and passageways it blows cold.so only 2 vents blows hot air ,the front roof ac don't work but the lights come on for the heater ,for the front ac I think the fan is bad
Darren, Where can I take a look at the test wiring extension kit? I looked but didn't see it in test equipment - unless I missed it. Thanks
Hi Rick, the test leads that Darren mentions in the video will be available on our website (www.t3interface.com) in the very near future. Feel free to sign up on the website to be notified when they are available. Thanks for your interest!
I had to replace my thermostat on Atwood 7920-ii bc I accidentally melted it with a buddy heater. Now furnace turns on for about tens seconds and the blower is barely pushing then trips 5-amp fuse on the furnace. Any suggestions on how where to look?
Thanks nice job god bless
I have a new grand design rv and the furnace, dometic, fires up when the thermostate calls for heat. Blower turns on, ignites for 10 seconds, flame goes off, waits 20 seconds, then ignites again and runs for about 1 minute 30 seconds, then flame out, blower runs for a bit then off. Same cycle whenever there is a call for heat. Any thoughts?
Was this before or after your coffee?
what will cause power surge when turning on furnace
fan went out on suburban SF 35q, put fan in and furnace starts up ignites starts to get warm but then ignitor shuts off.
When will the times be available for order on your website?
Hi Justin, you can sign up to be notified when the tools are available on our website, or just send us an email at info@t3interface.com. Barring any unexpected delays, we expect to have the AquaHot Diagnostic Switch, Test Lead Set, & LP Tap Jig available in February!
@@MyRVWorks thank you. I found the sign up. Appreciate it. Found your page a few days ago. I am signed up to go to NRVTA in a few months. Been RVing for 10 years and I’m tired of working construction.
Brilliant! Now if I watch a few more times it might stick in my thick skull.;-}
Does the thermostat have to be on to check voltage
My furnace runs on shore power but when on Battery it does the same thing this one does. Fan, ignite , burn out. Repeat. Plug it into shore power and there is no issue. What up with that?
I was trying to watch it all the way through... You sure like to talk😂
Why would outside temp have an effect on when heater works?
The outside temperature is more a function of how I work - LOL. It was cold this day so I brought the furnace into my our service trailer to work on it. Sorry if that was confusing...
Maybe my 6v batteries are getting old. Just wont ignite. All of a sudden after switching propane tanks.
My furnace has started burning too hot and trips out on over temp PLEASE HELP!
My surburban furnace lights heats up then kicks off on the first use. Then, furnace tries to light 3 times will not light and locks out. You hear it clicking and lighting but flame goes out after a second or so. Anyone have a clue?
His guy loves to hear himself yab
Intermittent failures are a real pain in the butt.
12:37 the back of where? I think you maybe a little confused sir. that's a tool bag you're pointing the rear of....😂
I have a problem with the furnace it turns on & Runs an and turns off in a few minutes, What could my problem be?
The first thing the furnace will do is a pre-Purge of about 15 to 30 seconds. Then it will try to ignite. After ignition it will do a post Purge for about 90 seconds. So my question, do you actually hear the furnace igniting and running or do you just hear the fan running? If you get ignition but the ignition extinguishes within a couple seconds, that is an indication that your DSI board is not detecting the flame. It could be low LP pressure, the gap of the electrode to the burner head, the igniter electrode itself, or the board. If you look at our video playlist we do have quite a few videos that cover every one of these topics. Good luck and try to stay warm.
It just Runs, no no click or igniter
Thank you! I understood well.. I’m fixing mine and the intermittent problems are the headache, I haven’t worked on furnaces much , also I worked for an rv guy ,. I’ve done all diagnostics on my own, without making phone calls. And it’s in isolation to the motherboard or the igniter for mine. But I am ruling the motherboard. Because my furnace shuts down. It’s different when you can grab the parts out of the service truck. L O L, And why I think it’s my motherboard is because the motherboard gets warm and then the problem acts up
If you have 2 miles to get to your destination, why travel 100 miles to get there ??
I just looked for the lead set you are making and I couldn't find it anywhere.
myrvworksstore.square.site/shop/tools/3
He talks so darn much. 5 minutes on the introduction before he even started to troubleshoot
Actually it was 6 minutes but after that what a wealth of information. I've learned more about my furnace from this video then all of UA-cam combined thank you for such an in-depth tutorial
You seem like you can do better. I say this because you are only adding negativity. No positivity. I would be very interested to see your video on furnace troubleshooting. Please let me know when it is completed. Remember to keep it brief and focused. Thank you.
Blah... Blah... Blah OMG Just Get To The Point!!
"If you're supporting us" Every viewer (Not just patreon) is supporting just by watching your videos. Aren't these videos monetized? That's a pretty poor choice of words and will turn off many viewers.
Can you recommend a good online RV parts store? I’m having a heck of a time finding a furnace blower motor part #233062