In my gas fitter program (Canada) we call them switches. This is the first time I’m hearing them called contacts. All good. Ps. DO NOT test continuity while the relay is connected to a live circuit.
I got a new 90-340 fan relay where the condenser is and every time the AC turns on, it makes a loud single click... is that normal? I ask because the previous relay wasn't as loud.
i have the same meter,noticed one thing the beeping sound is very low, hard to hear it outside while working if you more units next to you that are ON,
Relays are used with electrical loads at a range of about 10 amperes or less, while a contactor (think power) load capacity is greater than 10 ampere. In other words a Relay can be used to control a contactor but generally not the other way around. In this case a thermostat would have a 24 volt rated relay powered by the a 5v circuit board that powers the 24 volt coil on the 110/220/480v contactor.
I think the purpose of 24v relays are to be able to use small size conductors that fit in smaller enclosures to control larger loads, thus saving space and cost.
My 90-340 is 8 pin for 8 pin socket (like this one). But when I search for a replacement to order I get half with 10 pins - Will a 10 pin 90-340 fit my socket - extra coil blades hang over the socket and not touch anything?? I cannot find a different marking or part number for 8 to 10 pin 90-340???? All sects are the same but shouldn't the 8 and 10 pin have different part numbers? Grainger only shows a 10 pin in pic.
Bryan can you expand on the amp ratings of the contacts. When it says 230 volt or 460 volt, would that be if you somehow applied 230 volt measured to ground on one contact, or is that if you applied 230 to both sets of contacts (120 per contact, but ultimately a 230 volt load).
Put a Triac in place of the switch and control the whole process with a microcontroler (arduino etc). Going to be my next project ,to replace the mechanical sequencers. Should be able to dial in efficient and more accurate timings.
I need your help I don't have knowledge about this relay problem I have is when I turn on the heat the blower turns on but not on cold.i installed a new capacitor 7.5mf the blower works I'm trying to figure it out I don't have a working diagram on a gibson 2.5 ton hvac thanks
HVAC School how would I wire this relay to power 2 well pumps from a switch in the house. The switch on position would power one pump and if you turn switch off it would power the other pump. A wiring diagram for this would help alot
Matthew Anglin pretty simple actually. Tl1 &T4: line in (hot & neutral or both hot if running 240V) T2 & T5: pump 1(normally on) T3 & T6: pump 2(on when relay is energized)
I have an older sears furnace, no board just relays that fan comes on immediately, it works otherwise but im not sure its wired correctly i removed the fan limit wire and it didnt care at all, the 90-340 switch has terminals 1 and 4 jumped with a wire, removing that the fan doesnt run, why would a jumper wire be placed on 1 and 4. Relay tested good though. Wouldnt fan limit wire have to go to the coil connection.
always check your wiring diagram first,a lot of furnaces have a limit on the fan shroud that if it fails the fan will never shut off as a safety in case of high limit opens you wont have flame and no fan
Thanks for making the vids. Starting HVAC school in the fall and these are a great supplement!
How did the school and work go?
Welcome gues all
I finally understand the contact ratings with your explanation. I can't thank you enough!
Another nice video tutorial ❤️
Again enlightened me about RELAY. thanks for sharing your knowledge ❤️
thanks .... so simple yet i learned alot . i think i blew up a thermostat today watching this video would of helped
Thanks for an informative video that even I can understand. Well Done!
Can you please do this with a fan blower ? I guess thermostat, to relay, to fan. It would be great
In my gas fitter program (Canada) we call them switches. This is the first time I’m hearing them called contacts. All good. Ps. DO NOT test continuity while the relay is connected to a live circuit.
I got a new 90-340 fan relay where the condenser is and every time the AC turns on, it makes a loud single click... is that normal?
I ask because the previous relay wasn't as loud.
another great presentation thanks
I'm a maintenance tech that has hands on experience but it's really good to get detailed and very educational explaintion 🙏👊👍
Excellent video! Thank you!
i have the same meter,noticed one thing the beeping sound is very low, hard to hear it outside while working if you more units next to you that are ON,
So great
Can I replace my 91-9301 24v with this one. Can not find one with exact parts number. Any other alternative? thanks
Can you make a video on how to use it to wire an air handler? Thanks
You should show how to wire this relay to control an air handler.
Too much time explaining the same point rather than show in what scenarios you can use it on 2cents
Unfortunately relays like this one are becoming obsolete. Just like cars swapping boards is the future.
Relays are used with electrical loads at a range of about 10 amperes or less, while a contactor (think power) load capacity is greater than 10 ampere. In other words a Relay can be used to control a contactor but generally not the other way around. In this case a thermostat would have a 24 volt rated relay powered by the a 5v circuit board that powers the 24 volt coil on the 110/220/480v contactor.
I think the purpose of 24v relays are to be able to use small size conductors that fit in smaller enclosures to control larger loads, thus saving space and cost.
I used to study in Germany ,
The way of your teaching reminds me German technical schools.
Great job 👏👏👏👏
Please continue .
I would love to know where you got those nice insulated alligator probes.
Great video Bryan! Thank you
Can you explain how to wire this switch to a Goodman unit. Thx
Doesn't the double pole/double throw refer to the number of circuits you can control with the relay (the fact that you have two sets of contacts)?
Great explanation! Thanks for the video
My 90-340 is 8 pin for 8 pin socket (like this one). But when I search for a replacement to order I get half with 10 pins - Will a 10 pin 90-340 fit my socket - extra coil blades hang over the socket and not touch anything?? I cannot find a different marking or part number for 8 to 10 pin 90-340???? All sects are the same but shouldn't the 8 and 10 pin have different part numbers? Grainger only shows a 10 pin in pic.
By far the best explanation I have seen.
Very good I like it
Bryan can you expand on the amp ratings of the contacts. When it says 230 volt or 460 volt, would that be if you somehow applied 230 volt measured to ground on one contact, or is that if you applied 230 to both sets of contacts (120 per contact, but ultimately a 230 volt load).
It's the total voltage applied across one contact. In the case of 230 / 240V that is two opposing 120v sine waves
Very good demonstration. Many thanks!
Put a Triac in place of the switch and control the whole process with a microcontroler (arduino etc). Going to be my next project ,to replace the mechanical sequencers. Should be able to dial in efficient and more accurate timings.
I need your help I don't have knowledge about this relay problem I have is when I turn on the heat the blower turns on but not on cold.i installed a new capacitor 7.5mf the blower works I'm trying to figure it out I don't have a working diagram on a gibson 2.5 ton hvac thanks
You may have a bad board or a bad thermostat.
ua-cam.com/video/y59w9LcumlE/v-deo.html
Very good job breaking it down. I was able to understand very clearly. Thank you!
HVAC School how would I wire this relay to power 2 well pumps from a switch in the house. The switch on position would power one pump and if you turn switch off it would power the other pump. A wiring diagram for this would help alot
Matthew Anglin pretty simple actually.
Tl1 &T4: line in (hot & neutral or both hot if running 240V)
T2 & T5: pump 1(normally on)
T3 & T6: pump 2(on when relay is energized)
thank u for the help great video much much aprociatate
I have an older sears furnace, no board just relays that fan comes on immediately, it works otherwise but im not sure its wired correctly i removed the fan limit wire and it didnt care at all, the 90-340 switch has terminals 1 and 4 jumped with a wire, removing that the fan doesnt run, why would a jumper wire be placed on 1 and 4. Relay tested good though. Wouldnt fan limit wire have to go to the coil connection.
always check your wiring diagram first,a lot of furnaces have a limit on the fan shroud that if it fails the fan will never shut off as a safety in case of high limit opens you wont have flame and no fan
Thank you for a great explanation
Well explained, thanks
Thank you!!!
What meter is that?
Testo 770-3
Tanks brov
good demonstration thank you for making videos
great video, is that how a compresor heater is wired, normally closed?
compressor heater if your talking like a belly band,is always wired hot 240v,not switched