HVAC Questions? Ask an HVAC Expert for Answers ASAP
Ok, that will work
turn breakers off. the on the relay that is burned..there are 2 wires that come to as from main power and then wires leave it and go to the compressor.
Touch one meter lead to the power side on one terminal and then touch the metal cabinet with the other lead. tell me if needle moves.
ok, now this may be tedious..
we want to remove a component at a time from the syatem while ohming out the circuit.
Ex....mark all motor wires and unhook..then ohm...if still moving...the unhook from a relay and ohm...the remove wires from compressor and ohm..look for domed tops on the capactiors (the round cannisters the size of a pop can).
Eventually you will get no needle movement to ground....this will identify the last item you unhooked as having the short.
Lets say you remove 3 wires that attach to motor...you would put one lead on the motor wire and the other to ground...to that all the motor wires...if there is no needle movement then the motor is not shorted..
Then remove wires from compressor and test compressor to ground.
Plus I am available for 30 days to help..
so does the needle move on just the component?
Then this would mean you daodged a bullett.
This is a common part to short. It is called a contactor. Make sure all wires are identified and marked. Remove contactor and swing by a local cooling shop and get a new one.
Let me know if you need help installing the new one.
Very observant....the terminals outside are copied to the thermostat. And yes the control you pulled wires off from and still read a needle movement will be the unit to replace.
You just respond to this same thread.
You have 30 days of follow up after accept is clicked....this should give us good time to get it solved.
Ok, if you can get the part tomorrow just respond and let me know.
was there wires attached to the contactor when you ohmed it out and the needle moved?
Do you have electrical tape?
Start at the compressor and follow the wires back to the contactor (part replaced)
Take the wires off that go to the contactor.
You will see 3 wires leave the compressor and 2 go to the contactor and one to the pop can size cylinder. We want those 3 unhooked and taped just well enough so wire ends are covered.
Then turn on and tell me result.
Look in the section under the fan in the top.
Down at the bottom you will see a "can" that is the size of an oversized paint can
It will have copper pipes attached to it and wires out of the bottom.....3 of the heavy wires will lead back to the part you replaced and the capacitor.
The compressor will be directly under the fan motor in the top of unit.
Believe it or not it is starting to fall together. Now...when you first started...you said a breaker labeled heat trips....
Is that the only breaker to this unit?
And also, you see where the main power comes in the unit at lower right...then 2 big black wires attach where it meets up with 2 big yellows and 2 more blacks?
I need a full pic of the area to the left....showing the big wires that lead there.
Put all wires back in unit. Turn off/leave off the heat breaker.
Go to thermostat and have all wires hanging loose but not touching each other.
Have the AC breaker on.
Take the red wire at thermostat and the green wire and twist them together.
Tell me if fan kicks on.
Thank you..now the twist the red, green, yellow and orange (wire that was on O)
do this with the ac breaker off...then turn on after wires are connected.
correct...I forgot about the blue being yellow....good catch
red, green blue orange
I am betting the yellow is bad..since it was swapped with blue.
take the thermostat wires off at outdoor cicuit board....breaker for ac on..use short wire an cross r to y terminal and tell me what happens
All the wires on the R, G, Y,W2 C etc...are all signal wires from the thermostat.
Label what went to what terminal. Remove all. Juper r terminal to Y and tell me if compressor and fan in top start.
Now at circuit board...R to G again should do fan
but from inside r to g made fan run right?
upper compartment far left..big block transformer far left is a rocker switch. press that and see if it was tripped.
and ac breaker is on?
and small trip switch on transformer still reset?
And can you read 24v ac at terminal R and C (not G this time).
With meter lead on R and meter lead on C was there 24v?
The terminals you have on the circuit board...
are they R, Y, G, O, C, W, W2?
I know this is tiresome and redundant but I want to be sure...and careful.
now try jumping r to o and tell me if you hear a click
now try R to W2
Now...we know the reverse valve activates
We know we have 24v
Now try R to Y again and then R to G again.
but this time ...actually install the jumper in place on the screws and tighten and wait a couple minutes to make sure we get by the delay timer if present.
The only thing we DONT want to do is short R to C or the transformer will trip again.
Rats..we are so close...now we know compressor and fan are active.
Can you see into the blower area where the fan is that circulates air through the duct?
The part you put in..if you press the center down does blower start?
is there a small plastic cover over the center?
Is there any way someone inside can verify if air came out of register?
We are at the end here and I just need to be sure.
very sorry, had an emergency. I work on hospital equipment and had a chiller for an MRI machine go down.
Ok...at the circuit board wire a jumper from R to Y...tell me if outdoor unit fan in top and the blower for registers runs. Then if so..wire R to Y and Y to O. Tell me if it ac's..if so we are ready to wire thermostat for cooling.
and last time for this...R to G just as a last effort on that circuit.
when you press in contactor what all runs?
give me a model number from the unit and I will see if we can make do.
see this pic but this time we are looking at the relay above the part you replaced. It has 2 black wires, a red wire, and then 2 smaller wires at the bottom end...do you see this and understand which part I refer to?
AC breaker off.
pull the 2 black wires
we want to contact these 2 wires.
Use a small nail that slides into each end or a piece of paper clip..tape the joint so no metal is exposed. The goal is to have these 2 wires off the relay and wired to each other.
Then turn ac breaker on and tell me if fan starts.
I see the wiring has been changed...brown to blue and a spliced red..
Now put a jumper (screwed into the terminals) on R and Y with the ac breaker off.
Then turn on breaker..go inside and check register.
now add a wire from Y to O.
turn breaker back on.
tell me if it cools out of register
Looks like some "rigging" has been done to this unit...
that fan should be cooling the freon as it circulates through the system.
Unhook O terminal and tell me if it feels the same.
now give a close up pic of the pop can looking items (capacitor)
Was there a definite difference in the temp out of register when O terminal unhooked?
And is the filter clean?
Here is what I need now.
Hook O terminal back up. Let it run for a bit..then take a temp coming out of register and tell me if it is 15 degrees cooler than the room temperature.
Thanks for hanging in there...most CT guys I know are not so patient....
What is room temperature?
Is O terminal wire still attached?
I do not know what was done with the wiring of the red, brown and blue control wires but it involeved the indoor blower relay.
We by passed that relay to allow the blower to come on with a call for cooling (R to Y).
With the relaay bypassed and the compressor, outdoor fan and indoor fan running we should have a discharge temperature of at least 15 degrees cooler than the air being sucked in.
We know the motor works but has been rewired, we know the fan in top works, we know the compressor works because temp of air is different when O is hooked or not hooked.
So, we have all the major items accounted for. But it appears there is a cooling issue. With O unhooked it goes into heat by default. With O attached it is supposed to cool. With 99 coming out of register shows the air is actually being heated...which leads me to think reverse valve dropped out.
If the R, Y, O is jumped together and the air coming out is warm....we have an issue with either too little freon, or bad reverse valve.
Is it still blowing hot air?
then the reverse valve is stuck, bad etc...
The reverse valve is in the area by the compressor
I hate giving in , as you can tell, but the components are all accounted for...just a glitch left with the Heat/cool reverse valve.
I thank you for your extreme patience, but at this point I would have to recommend a tech to inspect the reverse valve.
If the valve itself needs replaced it means removing freon and brazing in a new valve body.
If it is just the coil on top it is easier.
I really apologize but I have no working information of dealer/contractors in your area.
I really wish I could help more.
red to r = 24v
green to g = indoor blower
yellow to y = ac compressor
This must be a heat pump also.
The biggest culprit of the blown fuse is damge to the thermostat wire that runs from inside to outside.
remove the thermostat wires from circuit board.
replace the fuse
install the R wire and the G wire...test fan on function from thermostat.
if ok add the Y/W1 wire and O terminal wire.
sorry but I have to go offline for a 20-30 minute break.
I am glad you got one going at least..if new info pops up let me know.
Is the breaker on to the outdoor unit? Fuses in disconnect box on side of house by unit?
Is the filter at indoor unit clean?
Is the underside of the indoor coil clean?
Is the outdoor coil clean?
If those issues are ok then it is likely a loss of refrigerant issue.
As far as tip....dont worry about it as you have already paid more than most.
I thank you.
Yes...putting in freon is a touchy balance. Too much ruins compressor, not enough = no cooling.
Hopefully you will have a string of goodluck soon...I really wish you well
A set of refrigeration gages.
And a jug of R22 refrigerant.
Would help if you knew anyone in the business since to get the r22 freon you must be certified.
It can only get better....good luck in the new job.
That would cause the issue..the air is not all forced through the coil thus it mimics a dirty filter or bad blower.
Set fan "on" and run with ac off for 40 minutes. This should defrost the coil,,replace all panels and then try...let me know.