HVAC Questions? Ask an HVAC Expert for Answers ASAP
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Have you checked the switch on the side of the furnace? The breaker? If you push in the switch with lower panel off, are there any LED lights on?
No lights at all.
and I've checked the breaker
the switch is just a plain old light switch, right?
I'll check it again, hold on
OK, switch was in off position, and the condensate pump came on, but still no power to the thermostat display, and no movement in the unit
pump came on when I turned it on (though for some reason it was wired to be in the "off" position)
Did you check to make sure blower door is on tight? If it is, try taking the lower panel door off and seeing if the fuse on the control board is blown. Many furnaces have a blade type fuse.
I think the fuse MAY be blown, but where would I find it on the control board?
it's not apparent
Many furnaces have a fuse like this on the control board. I don't have a model number or specifics on your furnace, but check and see if it has this type of fuse.
just trying to figure out where that might be on the board
It may not have one. It would be sticking out and apparent (on the board) if you had one.
doesn't appear to have one
AND there was a red LED blinking
and the thermostat seems to have power all of a sudden
but when I depress the door panel switch, the LED goes out
Are you there?
Sorry, just ran down to see what it was doing
so no fuse
No fuse in the furnace?
and when the switch is depressed by the door panel, it shuts down the thermostat which, when the red LED on the bottom of the unit is blinking and the switch is NOT depressed, has power
no switch on the control board, no
How did you hook up this new blower door switch?
I cut the old leads and replaced them with smaller ones that fit the switch in question
Gosh, i wish I could show you how things look via FaceTime or skype or something
OK, there should be two leads that attach to the switch. Can you turn the power off and take those leads off and jumper (tie) them together thereby bypassing the switch?
I can do that, yeah. Just a second
OK that's done
still just a blinking red LED at the bottom of the control unit
Now turn power on and see if it works
power is on
that's why the LED is blinking
Is there a code legend somewhere around that control that tells what that blinking means?
I'll go down to the basement and take a look
it's flashing, though without a previous point of reference, I can't say if it's "fast" or "slow"
and the codes are "normal, no call for heat" if slow
which I guess is the case
and "normal, call for heat" if fast
which I don't think is the case
the thermostat is set to 74
with the ambient temp at 76
and the thermostat says "wait"
So it sounds like your furnace has power and 24 volts. But the thermostat is "dead"?
I was able to start the fan though
the thermostat is an LCD readout
OK and it says "wait"?
it's lit up
That is the delay when in a/c mode
and I can make alterations to the desired temp, etc
and start the fan
so what does that mean?
give it 3-5 minutes
Then it should work
I put a wire nut on the two exposed switch leads
OK, I just wanted to make sure it wasn't the new switch
I think the switch they sold me at the electronics shop isn't the same type as the switch I removed
I think this one BREAKS the current when depressed, rather than the other way around
Yeah, better to get an OEM replacement
like a fridge light
There are many sites that sell Trane parts
Ebay, my man
so it seems like I was basically on the right track, just didn't have the right switch
Go to an HVAC site that sells Trane parts
still waiting to see if it comes back on
It takes a good 3-5 minutes
Ok, seems to be running now
so I should be OK with it jumped like that, but will want to put in an oem switch, right?
Yes, OK to leave jumped for now
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Have a great day