After watching several you tube videos on this, I was not quite sure about a few things. Your video cleared up all issues. It was nice to hear each wire explained. Thanks.
The 120 volts read to ground means absolutely nothing when troubleshooting a 240 volt compressor, only that the transformer feeding it has a center tapped secondary. With the contactor closed, you would read 120 volts to ground from both L1 and L2, even if one of the 240 volt line conductors were open, 240 volts were not present at the contactor, and nothing could run. You would be reading 120 volts through the compressor motor windings giving the false impression that 240 volts were present between L1 and L2. This happens when fused switches are used for condensing unit disconnects, and one fuse has blown. Always check for 240 volts line to line at your equipment, and not for 120 volts to ground.
Very we'll explained Zack. I always look Foward to watching your vid. What happened with David and Ralph haven't seen them post any vid lately . Hope there doing well and they post vid soon.
Great vid. Love all the electrical stuff. Changing it out when it looks rough is a good call. But I'm wondering for larger contactors, I've been told measuring voltage drop is more accurate, how exactly should that be done?
Hi Guys! Is there any good video out there on wiring basic 24v relays, I'm in my first year and I'm not having any issues in the classroom but when I hit the shop and start wiring I'm getting confused. Any suggestions? Thanks in advance!
I need to replace a contactor and its FLA is 25 and Resistive is 40 amps its a 24v, do I need to get the same exact one or can I get a 30 amps FLA? or can I use a 2 pole contactor?
If you don’t have a signal for it to come on it won’t close. Check to see if you have 24 V between the Y and common wires. If you don’t understand what I’m saying it might be best to call a technician.
I'll tell you why I asked. I am off grid and use solar panels to power my freezer. I want my freezer to come on when the Sun comes up, so I can take advantage of the solar power in the am. I'm wondering if I can hook I hate separate solar panel up to the low side of the contact her to trigger the freezer to come on when the Sun comes up.
insight needed anyone! had a compressor in a heat pump the other day not pumping or sucking. the suction line pressures dropped maybe 5 psi after starting. replaced the compressor aND STILL SAME SYMPTOMS. what are your thoughts on this before recovering any more refrigerant. half stuck reversing valve? i know when there is a blockage (txv/filter) the pressures are exaggerated and you will know but this...hmm.
May be not more videos make by David and Rafal because tbey got cut by the state. Please use this videos for HVAC apprentices only. YOU guys never going to see big corporations doing video to the public like that. Watch for state they following videos like this one ,that can may be very injury or dead.
Very clear and concise video! Currently headed back to HVAC school at night to finish what I started 3 years ago.
After watching several you tube videos on this, I was not quite sure about a few things. Your video cleared up all issues. It was nice to hear each wire explained. Thanks.
Thanks for posting your training videos. Most people take this stuff for granted, a refresher is always a good thing. Keep up the good work.
Ray
Thanks Ray
The 120 volts read to ground means absolutely nothing when troubleshooting a 240 volt compressor, only that the transformer feeding it has a center tapped secondary. With the contactor closed, you would read 120 volts to ground from both L1 and L2, even if one of the 240 volt line conductors were open, 240 volts were not present at the contactor, and nothing could run. You would be reading 120 volts through the compressor motor windings giving the false impression that 240 volts were present between L1 and L2. This happens when fused switches are used for condensing unit disconnects, and one fuse has blown. Always check for 240 volts line to line at your equipment, and not for 120 volts to ground.
Thanks for sharing your knowledge.
Great walk through of the contactor circuitry Zack !! Take care, Brett
Thanks Brett
Perfectly explained thank you
Another nice job. Keep up good work.
Thanks David
Another Great Video From Talyn! Liked!
Very we'll explained Zack. I always look Foward to watching your vid. What happened with David and Ralph haven't seen them post any vid lately . Hope there doing well and they post vid soon.
I am not sure about David, but Ralph is doing well (fixing furnaces). Thanks for watching.
Awesome job
Thanks for the vids...you do a great job!!
Brent
Thanks Brent, I really enjoy it!
thanx
Great vid. Love all the electrical stuff. Changing it out when it looks rough is a good call. But I'm wondering for larger contactors, I've been told measuring voltage drop is more accurate, how exactly should that be done?
Voltage drop can be measured across the contactor poles. I.E. L1 to T1 or L2 to T2
thank's zack for sharing!!!!!
Why do some HVAC companies use double pole contactors instead of single pole?
Nice video Zach!
Thanks Rob
Great, What u do when its buzzing on and off all the time ? on contactor, new one/old one. not cooling but fans run.
Hi Guys! Is there any good video out there on wiring basic 24v relays, I'm in my first year and I'm not having any issues in the classroom but when I hit the shop and start wiring I'm getting confused. Any suggestions?
Thanks in advance!
I need to replace a contactor and its FLA is 25 and Resistive is 40 amps its a 24v, do I need to get the same exact one or can I get a 30 amps FLA? or can I use a 2 pole contactor?
Whats the purpose of having a single pole contactor? Why not just make everything double pole? Could they be interchangeable
Yes, they can be interchanged. I do not know why they prefer single pole. That is a good question.
Mine keeps bussing always
I do not have any power at the top of my switch but I do have 240 at the bottom , is the contractor bad
If you don’t have a signal for it to come on it won’t close. Check to see if you have 24 V between the Y and common wires. If you don’t understand what I’m saying it might be best to call a technician.
So the low side is completely different on high voltage side. could you use 12 volt DC to operate the contactor on the low side?
I'll tell you why I asked. I am off grid and use solar panels to power my freezer. I want my freezer to come on when the Sun comes up, so I can take advantage of the solar power in the am. I'm wondering if I can hook I hate separate solar panel up to the low side of the contact her to trigger the freezer to come on when the Sun comes up.
Bob Vance the contactors I use specify AC coils.
+Bob Vance you need a 12 volt dc relay, 20 amp rated
insight needed anyone! had a compressor in a heat pump the other day not pumping or sucking. the suction line pressures dropped maybe 5 psi after starting. replaced the compressor aND STILL SAME SYMPTOMS. what are your thoughts on this before recovering any more refrigerant. half stuck reversing valve? i know when there is a blockage (txv/filter) the pressures are exaggerated and you will know but this...hmm.
Reversing valve is a good starting point
May be not more videos make by David and Rafal because tbey got cut by the state.
Please use this videos for HVAC apprentices only.
YOU guys never going to see big corporations doing video to the public like that.
Watch for state they following videos like this one ,that can may be very injury or dead.