Electric heat driving me crazy

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Qojoe

Qojoe

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Hey guys, to try and make a long story short my parents have electric heat in their house, the heat stopped working in the living room. They have a 24v thermostat that controls a 2 (240v) circuit (white rogers) relay. That relay went bad so i swapped it out, all was well and everything was working (btw this is the first time i have dealt with these relays). So i got a call saying the heat wasnt working so i stopped by and checked everything, and there was no problems. The heat was working perfectly fine. About 20 mins ago i got another call saying when they shut the tstat off half the heaters went off and the others got hotter. I am going to swap the relay out on monday again to see what happens but this has me at a loss. I read over the instructions about 5 times and looked at the schematic over and over. Im 100 percent sure i wires this thing correctly but im confused to why this might be happening. Do you think its defective? I will post a couple of pics of the relay im using. It was a direct replacement for the one they orignally had. Also btw 2 of the heaters i replaced (there the ones working) according to them and the 3 others are the olders heaters.
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Sounds like maybe you have lost one phase (L1 or L2) and the heaters may be wired incorrectly on top of that.
Check for the 45 second delay at turn on and turn off.
It sounds a bit like the two sets are in series when "on" and only one is across the lines when "off".

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How would i wire it? I did it exactly according to the schematic. The relay only opens and closes one believe

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Im not sure this is a picture of the one i swapped out, i purchased the same one

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Qojoe said:
ays). About 20 mins ago i got another call saying when they shut the tstat off half the heaters went off and the others got hotter.
Click to expand...

This is a fairly basic but functional heating element control. Did the blower remain on for say 90 to 120 seconds after all elements were off? If it remained on to cool the compartment, then I really don't see a problem. However, if the blower cut out with the first set of elements, and the others elements were energized after the blower stopped, then you have a problem.

The bi-metal strips that open the circuits will not necessarily cool off at the same rate. You might even be able to measure different resistance across the elements in switch heater #1 and #2, and the wattage of the switch heaters might be printed on the device. When one opens before the other, the one that is still energized will have a slightly higher voltage on it that will be pushing higher current as well. So, it will likely get hotter before it cuts out.

It is surprising that your family was able to tell that was happening. Did they have probes attached?
 
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That wiring doesn't quite look right is that a 120 or 240 volt transformer? Either way it looks like the secondary is tied into the line voltage/common?? You need to separate and organize the wires to clearly display their orgin so someone could figure out what you have. What is that out of a ptac or baseboard unit I've never see anything like that in a central air unit.
 
They have one of those little temp guns and measured the temp of the heaters that way. This is all electric baseboard heat and that relay has a 240v transformer

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Im not sure if this is going to help but i am going to draw a picuture of how i8ts wired. Im only going to one of the 2 circuits to try and keep it easy. But basically theres 2 circuits wired like this using this relay. This is the line side

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This isnt part of a central air system, this relay just allows you to control 2 240v zones of elec heat through one 24v tstat

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Qojoe said:
This isnt part of a central air system, this relay just allows you to control 2 240v zones of elec heat through one 24v tstat

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Click to expand...

Disregard the blower comment then. I still believe you are wired properly. The isolation of the 24v controls from the 240v line is within the switches. If you "autopsy" the old one you will likely see how that was done.
 
I actually plan on doing that, i have the old one in my truck. I was looking at it in depth the other day

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Update, so i went over today and checked the heaters. Everything was perfectly fine and wired correctly.

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