I really thought it was the run cap
#41
03-27-20, 08:39 AM
I'm going to assume I checked both correctly and get no reading. What's the next place to check upstream? Here's a pic of the control board in the furnace fwiw...
Sorry, about the orientation...seems to do something different with each pic.
Sorry, about the orientation...seems to do something different with each pic.
#42
03-27-20, 08:43 AM
Member
If you take that door off you will trip the safety switch on the door that’ll shut the unit down. It’s in the upper right of the photo.
Make sure you have 24V, which you probably do since the blower runs.
Then see if you have a call for cooling at the board.
Make sure you have 24V, which you probably do since the blower runs.
Then see if you have a call for cooling at the board.
weigojmi
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#43
03-27-20, 09:19 AM
Yea, it did shut off when I removed the panel which released the switch.
Again I have to ask about where to specifically check for the voltage and what you mean by call for cooling at the board? I know first step is to turn the ac on at the thermostat, then...?
Again I have to ask about where to specifically check for the voltage and what you mean by call for cooling at the board? I know first step is to turn the ac on at the thermostat, then...?
#45
03-27-20, 10:22 AM
Are you saying there should only be one yellow wire for Y? I can trace where the red one goes if that helps?
#46
03-27-20, 10:24 AM
Group Moderator
weigojmi
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#47
03-27-20, 10:58 AM
Member
Those red wires are likely running to an inline safety device that’s tripped, as PJ mentioned above.
That’s a field installed device, whatever it is. You’ll have to tell us what it is/where those wires go.
That’s a field installed device, whatever it is. You’ll have to tell us what it is/where those wires go.
weigojmi
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#48
03-27-20, 11:48 AM
So that red wire is split with the other half in the wire-nut and then running to this switch/float thing in the pan below. I would assume this would only trigger if the water level rose to switch level but as you can see it is dry.
#49
03-27-20, 12:05 PM
Member
You can check across the switch and see if it’s open or closed.
There may have been a clogged drain that tripped the switch and now it’s stuck open.
There may have been a clogged drain that tripped the switch and now it’s stuck open.
weigojmi
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#50
03-27-20, 01:35 PM
How do I do that, exactly? Since I haven't gotten any readings so far testing voltage I'm probably doing something wrong...
#52
03-27-20, 01:37 PM
Group Moderator
A condensate overflow pan is usually clean. I'd imagine that crap may have jammed the switch.
It should be a movable float. That looks like an older Aquaguard sensor by Rectorseal.
It may have some type of float and magnet system.
Unclip it from the pan and check it out.
It should be a movable float. That looks like an older Aquaguard sensor by Rectorseal.
It may have some type of float and magnet system.
Unclip it from the pan and check it out.
weigojmi
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#53
03-27-20, 01:50 PM
I don't think so because I got no reading on my meter. Where should each lead be touching? I tried all over the screws and wires where they connect.
Also, is it good enough that the system is "off" because the door is off or should I be turning the air handler off at the main light switch during these checks?
Also, is it good enough that the system is "off" because the door is off or should I be turning the air handler off at the main light switch during these checks?
#54
03-27-20, 02:05 PM
Not sure how one should look or operate but it doesn't seem damaged. The outer "float ring" recesses in freely if I turn it upside down or push it. I also cleaned up that debris around it but there wasn't any under it.
#55
03-27-20, 02:08 PM
Group Moderator
Make sure that ring slides down and see if you now have continuity across the switch.
You should be getting 24v to the yellow compressor wire now.
You should be getting 24v to the yellow compressor wire now.
weigojmi
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#57
03-27-20, 02:49 PM
Ah OK well that was my main issue at the air handler. I'll find an assistant to hold the switch. I was told a couple things to check. What should I check and in what order?
Probably also my issue at the condenser...I had the breaker off I think since I was advised it should be off at different times. Must have gotten my wires crossed so to speak...
Probably also my issue at the condenser...I had the breaker off I think since I was advised it should be off at different times. Must have gotten my wires crossed so to speak...
#58
03-27-20, 02:59 PM
Member
Condenser doesn’t need to be powered on for control voltage. The control voltage source is the air handler.
With power restored to the air handler you should have 0 V between R and Y when the unit is calling to run.
With power restored to the air handler you should have 0 V between R and Y when the unit is calling to run.
weigojmi
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#59
03-27-20, 03:15 PM
Sorry, lost me again. So I'm not checking for 24v between R and Y when AC is called to run (air is on) and all power is on?
#60
03-27-20, 03:21 PM
Member
When your air conditioner is calling to run, and the power is on, 0V between R and Y means you have 24V on Y because the circuit is closed. You should read 24V all the time between R and C.
weigojmi
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#62
03-27-20, 04:23 PM
Member
So that means you have control voltage, and your air conditioner is not being told to run.
Although your thermostat may have a time delay.
Although your thermostat may have a time delay.
weigojmi
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#63
03-27-20, 04:59 PM
Member
Join Date: Dec 1999
Location: San Diego Ca. USA
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Hi, I think you need a new contactor. The wires operating the contactor are much smaller than the wires that run the compressor.From your picture it looks like yellow on top and blue on bottom both connected to the contactor with spades that operate the contactor. With the power on put one lead on each spade if the reading is about 24 volts the contactor is bad, if the the meter reads 0 the problem is upstream.
Good Luck Woodbutcher
Good Luck Woodbutcher
#64
03-27-20, 05:18 PM
Member
Woodbutcher, the OP has no voltage to the contactor coil. It is not the problem with the unit.
weigojmi
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#65
03-28-20, 05:02 AM
When I checked the contactor voltage, I had the power off at the condenser. I believe it was suggested earlier that this was OK. Please confirm. I can start troubleshooting out there again if necessary.
Otherwise, anything else I can check inside? Thanks again for everyone's help thus far.
Otherwise, anything else I can check inside? Thanks again for everyone's help thus far.
#67
03-28-20, 06:56 AM
The thermostat is a Nest and about 4 months old. Haven't had any issues I am aware of to this point. Something related to current to check here?
#68
03-28-20, 06:59 AM
Member
Wait for the time delay and make sure the nest is calling.
The nest is a terrible thermostat, it’s the source of many problems and issues. I’ve removed and trashed hundreds of them.
The nest is a terrible thermostat, it’s the source of many problems and issues. I’ve removed and trashed hundreds of them.
weigojmi
voted this post useful.
#69
03-28-20, 07:13 AM
Making sure its calling is to check for 24V at the Y and R terminals there? Won't removing the cover affect this?
#70
03-28-20, 07:18 AM
Member
Have to put the thermostat back on the wall, and jump out the door switch at the furnace.
If no call jump out R to Y.
If no call jump out R to Y.
weigojmi
voted this post useful.
#71
03-28-20, 07:38 AM
Please explain what you mean "jump out" R and Y?
Regarding, door switch you mean it just needs to be pressed in so power is on while doing the above step?
Regarding, door switch you mean it just needs to be pressed in so power is on while doing the above step?
#72
03-28-20, 07:42 AM
Member
Press the door switch to close it.
You can put a jumper wire between R and Y to bypass the thermostat.
You can put a jumper wire between R and Y to bypass the thermostat.
weigojmi
voted this post useful.
#73
03-28-20, 07:57 AM
I think it would be easier to do this at the thermostat, no?
Like this? https://youtu.be/9Y_R9unnadI
Also, looks like he is suggesting turning power off at furnace while applying jumper. I only have a paperclip at this time to use so there would be no insulation.
Like this? https://youtu.be/9Y_R9unnadI
Also, looks like he is suggesting turning power off at furnace while applying jumper. I only have a paperclip at this time to use so there would be no insulation.
#75
03-28-20, 09:13 AM
Well hot damn, I bypassed the thermostat and the air came on. So I guess this is another data-point against Nest thermostats. I can't thank you enough for walking me through this. I learned quite a bit.
#76
03-28-20, 09:26 AM
Member
Another Nest bites the dust.
I know I sound like a broken record but the Nest is literally the worst choice someone can make for a thermostat. A worthless paperweight wrapped in a good marketing campaign.
You’d be best with a product from Honeywell or Ecobee. Although more expensive they are superior products.
Ive actually had Nests short out by themselves and cause damage to the furnace control board. A few others stuck on and wouldn’t shut off the furnace.
I know I sound like a broken record but the Nest is literally the worst choice someone can make for a thermostat. A worthless paperweight wrapped in a good marketing campaign.
You’d be best with a product from Honeywell or Ecobee. Although more expensive they are superior products.
Ive actually had Nests short out by themselves and cause damage to the furnace control board. A few others stuck on and wouldn’t shut off the furnace.
#77
03-30-20, 03:59 PM
meter set up
swap the red and black leads on the meter connection ports, turn the dial on 500.
you might want to see if your condensate pan is full of water or the condensate pump safety is open.
if the fan is running, you have 24VAC
you might want to see if your condensate pan is full of water or the condensate pump safety is open.
if the fan is running, you have 24VAC
#78
03-30-20, 06:46 PM
Group Moderator
@ hvac01453 ....... I believe you are a page behind.
The float switch was shown to be sitting in a dry drain pan and no pump.
You can contact nest and they will send you a new sub base at no charge.
The float switch was shown to be sitting in a dry drain pan and no pump.
You can contact nest and they will send you a new sub base at no charge.
#79
03-31-20, 04:12 AM
So I contacted Nest and they did some troubleshooting to humor me which pointed to their thermostat as the issue as expected. But would not replace it since it was out of warranty. I replaced it with a Honeywell and am back in business.
#80
03-31-20, 10:55 AM
Group Moderator
I'm surprised.
They will not usually send out a new thermostat...... just the sub base which is the problem area.
They will not usually send out a new thermostat...... just the sub base which is the problem area.
