Is my compressor bad or just need refrigerant?

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  #1  
Old 05-30-06, 08:23 PM
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Is my compressor bad or just need refrigerant?

System:
Trane Air Handler (circa 1994 is my guess) Model TWH030B140A1
Thermostat : some older model (no digital) Trane Weathertron
Heat Pump: A matching Trane model.

I purchased this house in December 05. I had to fix the blower relay with the help of some gracious individuals on this board. It is possible, but unlikely that I did something when I replaced it.

I am pretty famaliar with automotive a/c but don't know much about home a/c. Here is my problem.

It is getting warmer. I turned on the a/c, after about 45 minutes the temp did not go down one bit and it was not blowing any cold air. The fan was working properly. The heat pump unit, outside, had a fully working fan, but when I touched what I think should be the high pressure hose and fittings they were not cold. If I was working on automotive ac, I would say that the compressor is not turning on because: 1) it is bad, 2) it is not receiving the proper signal, 3) the refrigerant is low so it won't cycle on.

Before I pay for a service call for something silly (that could have happened when I installed the relay, but again this is very unlikely), is there a way to test any of these? I have no idea if the a/c was working when I took possession of the home b/c it has not been warm enough to test it.

Is there a way to troubleshoot this?

Thanks,
jon
 
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  #2  
Old 05-31-06, 03:48 AM
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Did it heat for you when you had it in heat mode?

Feel if the compressor is running?
 
  #3  
Old 05-31-06, 02:11 PM
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Originally Posted by Jay11J
Did it heat for you when you had it in heat mode?

Feel if the compressor is running?
Hi Jay11J,

Thanks for jumping in on this one.

The model is Trane TWN030c100A2 made in 1994

The system did heat the house during the winter. I should say this though. This was when the air handler blower relay was bad and it was "always on." It seemed to me that the "aux heat" light came on pretty often though, but then again I am not sure what is normal for this system. I did not "test" the heat, other than seeing that it did turn on, when I replaced the blower relay (it was too warm for heat by then). I don't know what this says about the heat pump. I do recall the fan on the heat pump spinning while it was heating. Does this help or tell you anything?

I have done some further diagnosis to answer your other question. everthing below refers to the heat pump and not the air handler.

When the high voltage in on and there is current coming from the thermostat/electric panel (what should be normal operating procedure for the a/c): the fan spins, the compressor does not start, and something in the unit "hums" (i will call this "hum(s)" from here out and it sounds like a florescent light that is going bad. You know that electric buzzing sound they make. That's sort of what this sounds like). I does not seem like the compressor is trying to start, meaning it is not hesitating, choking, or breifly starting and then stopping. Of course, I don't know what the compressor sounds like on this model, but I think I would be able to tell if it were kicking in.

If I then cut the high voltage to the heat pump: the fan stops (as you would expect), the compressor does not change its state (as you would expect), and the hum remains.

If I then turn off the thermostat or cut the power at the electric panel, the hum stops (as you would expect).

I have located two capacitors on this unit. One is smaller than the other, silver, and has three poles. The other is black, slightly larger in diameter, and about 1.5 inches longer. It has two poles and there is a large resistor soldered across the poles.

Should I check the capacitors? Does this tell you anything? Should I post more info?

Thanks again,
jon
 
  #4  
Old 05-31-06, 02:26 PM
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Replace the capacitors, they are cheap, do them both. Mark wiring locations and take the old ones with you to your favorite local HVAC supply house so they can match them. Oh dont forget to discharge them before touching them they carry quite a wallop LOL. May not be the problem but 12 year old capacitors should probably be replaced anyway so lets start there. You are not on any type of cash flow or time restraints are you?
 
  #5  
Old 05-31-06, 06:17 PM
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Replace the capacitors, they are cheap, do them both. Mark wiring locations and take the old ones with you to your favorite local HVAC supply house so they can match them. Oh dont forget to discharge them before touching them they carry quite a wallop LOL. May not be the problem but 12 year old capacitors should probably be replaced anyway so lets start there. You are not on any type of cash flow or time restraints are you?
Hi,

I am not strapped for time. I do, however have some "cash flow restraints" . Don't we all. Seriously, I really can't afford to put a new heat pump in, and if it seems like this is a possible solution (which it does) I'd like to start there. I guesss the unit is getting old, but if it still has life in it, I'd like to go this route.

The troubleshooting chart lists a Run Capacitor and a Start Capacitor. Are both of these for the compressor or is one for the fan (the fan is working)?

My last question is about discharging the capacitor. I have a 123 Home Improvement book that lists the process as. 1) buy a 20k OHM 5 watt resistor and two leads. Turn off main power, clip the two leads to the resistor clip the other end of the leads to the terminal on the capacitor and wait about 15 seconds. They don't say what to do with a three pole capacitor though. Radio Shack only has a 20k 1/2 watt resistor (will that work).

There is also a screwdriver process listed at the very bottom of this webpage. Is it correct?
http://www.arnoldservice.com/run_capacitors.htm
When he says to go to "chasis ground," I am correct in assuming this means to just touch it to ANY bare metal on the case.

I also am assuming that I leave all the wires on the capacitor when I am doing this (I know this sounds stupid, but I want to confirm it).

How do I tell if the capacitor is discharged properly? Obviously, I have a multimeter.

Sorry for all the questions, I don't want to get zapped.
Thanks

jon
 

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  #6  
Old 06-02-06, 05:53 AM
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Update:

I found the two relays locally, but they only had the start relay in stock. The dual 25/5 440 relay is coming in today.

Anyway, I figured I would get the start relay and go home and see if it alone fixed the problem. The first thing that was weird is that when I was "discharging" the capacitors, I never heard or saw any sparks or any evidence that they were charged. I used the screwdriver and arced them a million ways. So I installed the capicitor I had and fired up the system and the original problem/condition still remained. Afterwards, again, I when I "discharged" the capacitors there was no evidence that they held a charge (I should expect to see something right?). So I am going to pick up the other cap today and see if it fixes it.

The other thing is that (with power off), I checked to see if the compressor motor was shorted by measuring resistance from the three wires that come off the compressor and the ground wire. The meter never moved, which should indicate that the motor is not shorting to ground.
 
  #7  
Old 06-02-06, 04:12 PM
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How to proceed now?

Well, I installed new run and start caps. Still no change (from what I described above). I also added one of those superboost things and there was no change. 38.00 total, it was worth a shot.

Some interesting findings. Again, I may be wrong here, but thought I would hear or see some sort of "event" when i discharged the caps. There has never been any point where I had ANY indication that the caps were discharging. Does this mean they were not charged?

Also, there is a red blinking light on the board. it was blinking at about 1 blink per second. About every minute to minute and a half it would do two or three quick blinks in succession and then immediately go back to one per second. The paperwork indicates one blink per second is normal.

There never seemed to be any point where the compressor was trying to come on.

Any ideas on how to proceed now?

Thanks for the help,
jon
 
  #8  
Old 06-02-06, 04:34 PM
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hey jon well from your previous description we should be cooling now but sometimes it takes a couple of trys. OK now lets check the contactor, they tend to also make a nice buzzing noise when they go bad. I assumed it was OK since the condensor fan motor was running and typicall if bad no compressor or condensor fan. Lets verify that the center section of the contactor is pulling in and staying in when the thermostat is calling for cooling, it is handy to have someone click the thermostat onto cool while you visually observe the contactor in operation. If all good there, we will need to then verify that with the contactor pulled in, we indeed have 240 volts on the down (compresssor side) of the contactor. Holler back with test results, we may have to invest in a contactor for this bad boy. Since you have established a HVAC parts source we are almost guaranteed success barring a internal refrigerant charge level problem or bad compressor. Carry on soldier
 
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Old 06-02-06, 04:44 PM
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Let me start with: I am not an HVAC guy. I am an electrician but I do work on pumps (motors) and some HVAC but not enough to get you ionto the contols of any new fangled electronic controls. Since you don't seem to be getting too many respnses, maybe I can tell you how to blow things up.

I have had caps that showed no sign of discharging even when all was good and right. I wouldn't neccessarily put too much into the fact that they did not arc. Dont use your meter to check if they are discharged. If it is still charged, you may harm the meter. This is ususally one of the "faith" things. Make sure you have grounded out the terms, wait a half minute or so and do it again. They should be drained at that time.

If you have two caps one labeled as start and the other as run, you have a cap start/ cap run motor.
Now do the caps hook to a small relay? or is this all electronic?

The LED blinking is an indicator of problems (or all is well) The fact that it blinks other than the "all ok" blink, I would think it can tell you more, I just don't know what it is telling you. Maybe one of the HVAC guys will jump in on that.

OK, then on the motor leads, black, red, white? Using an ohmeter, check for continuity between each of them and ground and from each one to each other. B-G, R-G, W-G, B-R, B-W, R-W.

Do you have voltage at the contactor (relay) ?Do you have voltage on the motor side of the contactor when it pulls in, or does it pull in at all?
 
  #10  
Old 06-02-06, 05:07 PM
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hey jon well from your previous description we should be cooling now but sometimes it takes a couple of trys. OK now lets check the contactor, they tend to also make a nice buzzing noise when they go bad. I assumed it was OK since the condensor fan motor was running and typicall if bad no compressor or condensor fan. Lets verify that the center section of the contactor is pulling in and staying in when the thermostat is calling for cooling, it is handy to have someone click the thermostat onto cool while you visually observe the contactor in operation. If all good there, we will need to then verify that with the contactor pulled in, we indeed have 240 volts on the down (compresssor side) of the contactor. Holler back with test results, we may have to invest in a contactor for this bad boy. Since you have established a HVAC parts source we are almost guaranteed success barring a internal refrigerant charge level problem or bad compressor. Carry on soldier
Hey Former Member,

The contactor is working, meaning when "cool" is turned on, the contactor is pulled down and stays down, and goes up when cool is turned off.

I put the positive lead of my voltmeter on the downside pole (which was red and fatter than most of the other wires. it looked like it went to the compressor) that is one side of the contact. I put the negative lead going to ground - where the ground wire enters the unit and is screwed to the unit. This read about 124ish volts. I then put my positive lead on the other side of the contact (which was some sort of brownish wire - maybe faded I don't know). It also read 124ish. I tried multiple times and used both the 200v and 600v setting on my meter. all readings with respect to the contactor were 120ish.

Did I test it correctly? What's next Sarge?
 

Last edited by Forums; 08-11-06 at 12:46 PM.
  #11  
Old 06-02-06, 05:19 PM
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We need a reading between the two main lines at the contactor (it should be 240 volts) what you checked would seem to indicate 120 on each leg but sometimes you are only reading feedback thru the motor. Verify 240 volts on down side of contactor by checking L1 to L2 please, put black on one line and red on the other should get 240 wat you got man?
 
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Old 06-02-06, 06:10 PM
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We need a reading between the two main lines at the contactor (it should be 240 volts) what you checked would seem to indicate 120 on each leg but sometimes you are only reading feedback thru the motor. Verify 240 volts on down side of contactor by checking L1 to L2 please, put black on one line and red on the other should get 240 wat you got man?

Glad the wiring diagram was with the unit.

L1 L2 was not what I was checking before. According to my diagram L1 is a BR/Red (with other wires on it), and L2 is A FATTY Black which goes to the compressor (and a couple of other smaller Black wires)

Voltage between L1 and L2 is 252V.

Thanks.
 

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Old 06-03-06, 08:19 PM
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cruiserparts the 252 volt reading you got on the leads was that on the compressor side of the contactor?? if so and you have replaced the capacitor then we can be 99% sure that power is getting to the compressor. The 1% is that there may be a bad wire so we need to do a real close inspection of the compressor wires back thru the capacitor all the way to the contactor. I would probably not try to pull them off the compressor lugs though, sometimes on older units the lug is rusted and will break off and then we will be needing a compressor and thats no fun. A slight wiggle and tug is usually sufficent to be sure thay are secure to the compressor lugs. I have seen wires right at the capacitor that are nearly burned off so take a close look at those also. Sometimes the compressor internal high temp shutoff will stick open I am not sure how to cure that maybe someone else here has tryed something that worked? If I found the problem to be compressor internal and it was my own I would probably be tempted to take a 2x4 and a big hammer and give that sucker a slight whupping LOL Might not do any good other than making the hammer operator feel a bit better.
 
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Old 06-03-06, 08:34 PM
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Well if he would bother to read my post and check the wiring as I suggested, he would know if the thermals are open or not, but hey, my A/C is working just fine.

Thw other thing he can do is to take an amp draw reading when the stat calls for cooling (and the contactor pulls in). I have had compressors make absolutely no noise when trying to start but trip out the internal thermals due to a locked motor/compressor. In this case there will be an initial high current reading followed by a 0 reading. It will repeat this as the thermal resets and opens.
 
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Old 06-03-06, 08:55 PM
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ooh i like that suggestion on the compressor check {Quote "OK, then on the motor leads, black, red, white? Using an ohmeter, check for continuity between each of them and ground and from each one to each other. B-G, R-G, W-G, B-R, B-W,R-W."} lets do it. Do you have a contnuity checker and amp probe cruise man?
 
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Old 06-03-06, 09:08 PM
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NOTE: NAP pretty much cleared this up in a post below, so you can ignore this. I was tempted to just delete it, but I figured that somebody in the future might use this thread for reference and might find some value reading about my confusion!



cruiserparts the 252 volt reading you got on the leads was that on the compressor side of the contactor?? if so and you have replaced the capacitor then we can be 99% sure that power is getting to the compressor. .
Hi Former Member,

You mentioned checking L1 and L2, and after looking at the wiring diagram, I put my test leads there. Now, on the diagram, I realize that line voltage is going to the places that I measured (L1 L2), which explains why I got 252 (I measured where it was coming in, duh). So there apparently is 240 coming in and the contactor is operating. Is this what you were telling me to verify. I see that there are wires running to the compressor from both sides of the contactor and this is what confused/is confusing me.

Or do you need what is coming out of the other side? Should I check the other side of the contactor assembly. This side has two poles which are labeled T1 and a pole that is not labeled on the diagram (it seems to be associated with the fan). T1 has a red wire that is going to the compressor.

To clarify, what I checked earlier when I got 120V was on opposite sides of the moving metal blade of the contactor (see the prior post for descriptions of wires). This would be L1 and T1, but not between L1 and T1, but L1 going to ground and T1 going to ground. On L1 are wires were from the line voltage, on T1 there is a Fatty Red going to the compressor, a thin red going to the capacitor, and a red (which meets a purple) and goes to the fan.

I guess what would help me most is knowing if I should be checking the two poles that are on opposite ends of the metal blade that moves, or the poles on the same side of the entire contact assembly. There are 4 total poles.

Let me know and I will check it in the morning (too dark here now) and get back with you.

Thanks for hanging in there with me.
 

Last edited by Forums; 08-11-06 at 12:47 PM.
  #17  
Old 06-03-06, 09:10 PM
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Originally Posted by nap
Well if he would bother to read my post and check the wiring as I suggested, he would know if the thermals are open or not, but hey, my A/C is working just fine.
OOOps for some reason I didnt' even see it. I must have just been scrolling down to the last post (or that's were I was sent from the email notification). I'll read it now and see if I can understand it. Thanks for hanging in there with me. I'll be back in a bit.
 
  #18  
Old 06-03-06, 09:21 PM
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Originally Posted by nap
I have had caps that showed no sign of discharging even when all was good and right. I wouldn't neccessarily put too much into the fact that they did not arc. Dont use your meter to check if they are discharged. If it is still charged, you may harm the meter. This is ususally one of the "faith" things. Make sure you have grounded out the terms, wait a half minute or so and do it again. They should be drained at that time.
Thanks, it's good to know. I will keep grounding them multiple times and to themeselves.

Originally Posted by nap
If you have two caps one labeled as start and the other as run, you have a cap start/ cap run motor.
Now do the caps hook to a small relay? or is this all electronic?
I have a relay (in addition to the contactor we are describing in other posts)

Originally Posted by nap
OK, then on the motor leads, black, red, white? Using an ohmeter, check for continuity between each of them and ground and from each one to each other. B-G, R-G, W-G, B-R, B-W, R-W.
Coming from the compressor I have B/Bl, R, and OR. I imagine I should substitute the OR for W, correct? I'll have a go in the morning. Do I want continuity between them or not? Just curious.

Originally Posted by nap
Do you have voltage at the contactor (relay) ?Do you have voltage on the motor side of the contactor when it pulls in, or does it pull in at all?
I think that's sort of what I'm confused about. I think I have voltage at the contactor, it does pull (and remain) in. The two other posts I made describing when I measured 120V and when I measured 240 Volts might help.

Thanks again for the help. Sorry I missed your posting before.
 
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Old 06-03-06, 09:34 PM
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ooh i like that suggestion on the compressor check {Quote "OK, then on the motor leads, black, red, white? Using an ohmeter, check for continuity between each of them and ground and from each one to each other. B-G, R-G, W-G, B-R, B-W,R-W."} lets do it. Do you have a contnuity checker and amp probe cruise man?
I have a multimeter that will check contnuity. Is an "amp probe" a seperate instrument (I'm not sure of the terminology). My multimeter does have an AAC am setting that warns "10A for 30sec Max Every 15 minutes, Fused" Will this work?
 

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  #20  
Old 06-03-06, 10:03 PM
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have a relay (in addition to the contactor we are describing in other posts)
This should be a potnetial relay that cuts the start cap out after the motor starts. If this is bad, it will act like a bad cap. Checking is tough so lets do other things first.


I think that's sort of what I'm confused about. I think I have voltage at the contactor, it does pull (and remain) in. The two other posts I made describing when I measured 120V and when I measured 240 Volts might help.
what youwere checking when you checked from both contacts at the contactor is the voltage from the house to that point. While 252 is a bit high (240 is considered nominal) it is not a problem. When you checked each "leg" to ground, you were the 120 volts was correct but as tsubaki posted earlier, this can be misleading if not able to interpret correctly. What you checked is the same as if you checked term to term on a 2 pole breaker. That is how you get 240 volts.


Sorry I missed your posting before.
No biggie. I thought I was invisible for a bit there.

It sounds as you amp probe is not up to the challenge. You are probably dealing with 30 amps or so and it the motor is locked, you can easily hit near 100 for a moment or two. It sounds like you have an "inline" ammeter. A real pain. What we were hoping for is a "clamp on" meter

When checking continuity on the motor leads, disconnect them from anything else, being careful to not damage them (as Former Member pointed out earlier, this could be a bad thing) Basically when you are checking the motor leads, you are checking the windings. With a cap start/cap run there are two windings with a common. There chould be continuity between any one and at least one other. Give us the readings tomorrow and we'll go from there. You already checked for a grounded winding so there should be no continuity between any of them and ground which you already confirmed.

While you are checking, on the relay, is there 3 terms (look closely to see if you can see any numbers. I think you might find a 1 a 2 and a 5 , if I remember correctly and the relay is typical of what I run across) check continuity between each of the terms to each of the others.
 

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Old 06-03-06, 10:19 PM
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Originally Posted by nap
When checking continuity on the motor leads, disconnect them from anything else, being careful to not damage them (as Former Member pointed out earlier, this could be a bad thing) Basically when you are checking the motor leads, you are checking the windings. With a cap start/cap run there are two windings with a common. There chould be continuity between any one and at least one other. Give us the readings tomorrow and we'll go from there.
So is it fine to disconnect them as the wires come into the panel, or do I need to disconnect them at the compressor? If the former, I don't think I will mess things up. IF the later, who knows.
Originally Posted by nap

You already checked for a grounded winding so there should be no continuity between any of them and ground which you already confirmed.
I did this without disconnecting the wires, I just put them on the wires on the caps. Now that I think about it, and after examining the wiring diagram, this probably isn't right. I'll redo it tomorrow. Do I have to disconnect the wires or can I just measure from the junction point (cap or relay or whatever i trace it to) and ground?

Originally Posted by nap
While you are checking, on the relay, is there 3 terms (look closely to see if you can see any numbers. I think you might find a 1 a 2 and a 5 , if I remember correctly and the relay is typical of what I run across) check continuity between each of the terms to each of the others.
Will do.

BTW, I am correct in saying that I should always discharge the capacitors before doing any testing or work on the system, correct? I have been doing it everytime and wanted to make sure that was correct?

Thanks again. I'll give my meter a workout tomorrow.
 

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  #22  
Old 06-03-06, 10:28 PM
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Yes, always discharge the caps each time you check things. Sometimes you may have energized the system and forgot about it then POW, you take a hit. Just for safety sake, whenever you start readings, ground out the caps. I have this story about a guy that got hit with 10,ooo volts from a charged cap........but I digress, back to the pooint.

It ios better to disconnect the motor leads either at the motor or at the point they connect to a terminal. The reason being, in some cicuitry you will get feed through a component involved and get a reading that is not correct because of this so as a rule, you try to isolate each thing you are testing.

when taking off leads, find a way to either mark them with a corresponding mark on the appropriate term or make a small drawing of what is there.
 
  #23  
Old 06-04-06, 11:19 AM
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Originally Posted by nap

when taking off leads, find a way to either mark them with a corresponding mark on the appropriate term or make a small drawing of what is there.
Morning NAP,

I have some results (drum roll....)

I pulled the fan and found the following wire hanging off. I was at first concerned, but I think it might not be an issue. the compressor had three wires solidly attached (and two wires going to some sort of sensor that cradles the refrigerant tube. This may have been from a previous compressor (the wire that is attached looks like black speaker wire), although it is wired into the contactor still. I have no reason to think that it broke off. It may be left from an old compressor. But you may know more.

<img src="http://www.jonfritsch.com/fj40/connector.jpg">

I tested the following at the compressor terminal.

Continuity Test..
B-G No
R-G No
OR-G No
B-R Yes
B-OR Yes
R-OR Yes

Relay Check Continuity

1-2 Yes
1-5 No
2-5 No

Some other observations.
When therm/cool is switched on, the contactor immediatly engages. About 45 seconds later, I hear a call (click) that I think is coming from the relay, but I'm not sure.

BTW, here is the compressor tag
<img src="http://www.jonfritsch.com/fj40/compressortag.jpg">

Does this tell you anything valuable?

jon
 
  #24  
Old 06-04-06, 12:37 PM
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ok, if you go to this pdf page 22, you will see a diagram. It isn't your unit but it has the potential relay I speak of. It was the best diagram I could find and will work for what I need.

http://www.rvcomfort.com/pdf_documents/1976299.pdf

From what you describe, you have one of two things bad (or it could be both)

either the potential relay is bad or the compressor is seized.I think the potential relay is bad (if I remember correctly you should have a reading between 2 and 5 as well.

The clicking you hear is probably the motor tripping out on overload.

Now what I am going to describe to you can get you hurt if you do not follow directions exactly.
What we are going to do is simulate the potential relay doing what it does best.

How we are going to do this is with a insulated pair of needle nose pliers and an assistant and a 2x4.

. With the power disconnected remove the connection at term 1 at the potential relay. When you try to start the compessor (don't do it yet), you need to hold that wire to term 2 on the potential relay. When the contactor pulls in, hold the wire there for less than 1 second, then pull it free, keep it from touching anything, including you. Do not re-attach it to term 1 because if the relay is bad, it will put the cap back in circuit and you don't want that.

The compressor will either start at this point or not. Listen for that click you heard earlier or any other sound.

If you do not hear the click,and you get the wire situated, feel the compressor to see if it is running. Feel the freon lines, one should start getting warm and the other cool.

This would indicate that the potential relay is your immediate problem.

If the motor still clicks out, then it is probably the compressor.

Now to the assistant. Their job is twofold.

1. they need to turn on the unit when you are ready to do your thing. If the motor clicks out, they should shut the unit down as well.

2. (this is where the 2x4 comes in) if you any way get hooked into a circuit and are getting shocked, the assistant uses the 2x4 to push you free of the unit immedialtey after disconnecting the power to the unit. (you shouldn't need the 2x4 but sometimes people get excited and do not turn off the power before grabbing a person who is gettting shocked and end up getting shocked themselves.)

Just want to make sure, there is a disconnect near the unit , correct????



---------
so for a little explanation of what the relay is doing.
When you try to start the motor, the start cap needs to be utilized. Immediately after starting, it has to come out of circuit. Faliure for this to happen can damage the motor. You are just acting in place of that control system here. That may be why you are hearing that little click. the cap may not be getting pulled from the circuit and the resultant motor overload is tripping the internal thermal protection.

I would only try this a couple times at most (although if it doesn't work, the compreessor is probably toast anyway) but to avoid the possibility of damage, don't over do it.
 
  #25  
Old 06-04-06, 03:19 PM
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Originally Posted by nap
ok,

I would only try this a couple times at most (although if it doesn't work, the compreessor is probably toast anyway) but to avoid the possibility of damage, don't over do it.
Hey Nap,

Hmmm. I think my significant other is going to freak out when I ask her to help with this one. I will see how much the relay is (the local shop has been good about prices, the caps were only 28.00 total), and if its not to expensive I may just install it and see if it fixes it. I do have one rusty rivit on one of the exterior poles (but that may be normal).

Would you be able to tell more about the relay continuity test on the relay if I scan the diagram and post it.

BTW. Have you ever heard of anything like what I described in this thread... http://forum.doityourself.com/showth...524#post993524
 
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Old 06-04-06, 03:25 PM
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Yes I have. I think it is exactly what you thought it was, a heating element.

My dad had this put into his house when he built it in the 60's.

The relay shouldn't bee too bad price wise. I think it was less than $50, maybe less. It's been awhile since I had to price one.

Your diagram of the relay should be similar to the one I linked. In this case, there should be continuity between 2 and 5 and actually 1 and 5. If there is no continuity from 5 to anything, the coil is burned out.
 
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Old 06-04-06, 04:03 PM
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Originally Posted by nap
Yes I have. I think it is exactly what you thought it was, a heating element.

My dad had this put into his house when he built it in the 60's.
I can't find any evidence that I have a heating grid hooked up anywhere (no thermostat), no switch (other than the light and fan switch). I looked above the plaster and nothing. My guess is that this could have been shipped as some sort of option but was never hooked up? Did you dad's have controls or something? I will try to check it with my meter, but with 4 severed wires it may be difficult.
Originally Posted by nap

The relay shouldn't bee too bad price wise. I think it was less than $50, maybe less. It's been awhile since I had to price one.

Your diagram of the relay should be similar to the one I linked. In this case, there should be continuity between 2 and 5 and actually 1 and 5. If there is no continuity from 5 to anything, the coil is burned out.
I will have a look at the wiring diagram and compare.

Thanks again!
 
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Old 06-04-06, 04:14 PM
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I don't know how/ where it was actually tied into the power but we had thermostats on each rooms wall to control the stuff.

I would take a look at the breaker panel as well, you might find someting labeled/ relabeled that was for the heat. Just wouldn't want anybody to get hurt.
 
  #29  
Old 06-04-06, 07:18 PM
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Originally Posted by nap

Your diagram of the relay should be similar to the one I linked. In this case, there should be continuity between 2 and 5 and actually 1 and 5. If there is no continuity from 5 to anything, the coil is burned out.
Hmm..

I'm not exactly the best wiring diagram reader (but getting better by the minute!). I think mine is different. The one you posted on page 22 has four wires going into the relay (I think, but I may be wrong). Mine has three. The diagram I have (which matches what I have seen on my unit) is here.

http://www.jonfritsch.com/fj40/wdiagram.jpg
 
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Old 06-04-06, 08:02 PM
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I honestly can't tell on your diagram. I am getting older and the eyes fail sometimes.

Yes there are 4 on the diagram I linked.I only wanted to use that for reference. It was a nice clean diagram that I could use to help along.

The one in the link uses that "freeze switch" to change the circuitry when it is cold outside. Yours may have (actually should since it is also a heat pump)but it could be tied in elsewhere. Sometimes things are the same but look different because of where connections are made or drawn.

I tried to find your schematic online and had no luck.

Real simply though. It should have a wire from each of the caps and one from the motor. If it does, then I'm sure we are on the same page. By the diagram, the has to be continuity between 2 and 5 ,it is a coil for the relay and has to have continuity
.
I looked up some potential relays in a supply book I have. They listed at $20. Yours may be more because of the supplier or manufacturer but it shouldn't be too much more. Like I posted before, I think the last one I bought was around $50 or so.

Like I said, you can try it my way or try a new one but I believe yours is bad. That doesn't mean there isn't more, but at least this is one thing that is bad. Hopefully all that is bad.

The burned wire does concern me though. Try to find where it came from. If you can get a better pic of your diagram, I may be able to help with this.
 
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Old 06-04-06, 08:27 PM
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Originally Posted by nap
I

The burned wire does concern me though. Try to find where it came from. If you can get a better pic of your diagram, I may be able to help with this.
Hey Nap,

I posted a high resolution scan of the wiring diagram. You should be able to zoom at will.

From looking at the diagram and my unit, i now believe the broken thing I posted is somehow related to the "SUMP HTR." it has a black wire that enters L1, just like the diagram, and another black wire that joins with a purple and heads somewhere else. The diagram says this destination should be TDL "Discharge Line Thermostat". Clearly it is broken, but it is not obvious where it broke off from.

Let me know if the new scan is better.
http://www.jonfritsch.com/fj40/wdiagram.jpg

Thanks a million for you time.
 
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Old 06-05-06, 02:53 PM
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That's fantastic.

The "touch the wire here for a second then remove "would do what I was suggesting. If you don't want to try it, that's ok. Sometimes I wonder myself why I do things. Whatever you do, use caution and if you are uncomfortable doing something, you are correct in not doing it. Better safe than sorry.

The part labeled CSR at the bottom is the potential relay I spoke of. Yours does not have the freeze stat as in the drawing I linked so wiring will of course be different.

The wire that it broken:

Look at the top of the diagram, the two devices labeled "sump heater" and "TDL" Like I said befor, some HVAC things do make me think but I believe what that is is........wait for it...............waaaiiiittttt......................................................

it's coming........................................................................




a sump heater

The fact that you have a heat pump A/C would make that make sense. What the other thing "TDL" is is a thermostic switch to turn on the sump heater. The sump heater, I believe, is in the compressor unit itself. It would provide heat for the oil in the sump when it is cold. From what I can see, that not being hooked up should cause you no problems if only using it as an A/C.

Just tape or wire nut the end of the wire to prevent any shorts.

Now if you look at the top left corner at the CPR. That is your compressor. If you look at about 2:00 on the circle, it says "IOL".
that should stand for internal overload. This is probably what you heard clicking when trying to start the unit.

That, just as I said befor could be good or bad.

What we need to do is either replace the potential relay (CSR on the drawing) or jump the system as I described. If this doesn't get you going, I am sorry to say it is probably the compressor itself locked up and dead.
 
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Old 06-06-06, 04:26 PM
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Unhappy The verdict is in.....

Originally Posted by nap
What we need to do is either replace the potential relay (CSR on the drawing) or jump the system as I described. If this doesn't get you going, I am sorry to say it is probably the compressor itself locked up and dead.
I took the safe rout and just got the 29.00 relay.....installed it.. and.


.
.
.
.
.

.
.
.
.
.
.

No change. Nothing. Nada... Oh well, it was worth a try. At least I learned a lot about heat pumps, which is good.


I'll get the certified people out here. Any idea how much a compressor costs? Or should I replace the entire heat pump?
 
  #34  
Old 06-06-06, 08:44 PM
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Well that's a Da** with a capital D

Well, maybe one of the HVAC guys can help you with that part of compressor v. unit price and which is best, I do electrical only. Not certified to play with freon.
 
  #35  
Old 06-13-06, 06:43 AM
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Hey Nap,

Well, the HVAC service fellow came out today and confirmed that the compressor was locked up. So, at least my (with your help) diagnosis was correct, even if it is not the desired outcome!
 
  #36  
Old 06-13-06, 03:29 PM
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Hey that's great, or not. I guess it depends on which part you are looking at.

Glad I could help you at least try to save some cash. Sorry it turned out to be the compressor.

At least now you know more than you did before and can have pride in your attempts to DIY.
 
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