4 Burned Transformers and counting


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Old 05-13-09, 11:55 PM
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Exclamation 4 Burned Transformers and counting

Hello All,

First and foremost...I apologize for the long explanation...but I desperately need assistance troubleshooting the electric circuits on my Trane HVAC system. I know there is a short circuit somewhere, but I need assistance in figuring out what wires to check/test for continuity and/or voltage. My main concern is that the tranformers have been literally burning up (fire).

Now for some background info...this all started a few months ago. The heater was on, my son decided to switch to A/C mode while the system was running (which was probably a bad idea) and the system died. The first blown tranformer.

Did some research on here and after troubleshooting the system figured out I needed to replaced the tranformer. Decided to also replace the contactor on the outside unit since it was showing signs of wear (and because it looked kinda "smoky" so I though it could also be a culprit). The system was again fully operational. It worked like a charm for a few days, but then it failed again. My guess is that again, someone switched from Heat to Cool or vice versa while the system was running...but I'm not sure. The second blown tranformer.

Did some more research...since the troubles seemed to be originating at the thermostat, decided to upgrade to a programmable one. Swapped out the tranformer, again the system worked like a charm. Warned everyone about not switching from Heat to Cool while the system was running as a precaution. About a month later, my wife "forgot" she wasn't supposed to do that. The third blown tranformer.

Did some more research (after realizing that the themostat was not the problem)...read somewhere that the fan relay board might be to blame. Swapped it out along with the tranformer, and the system was fully operational again. It worked great for about 2 months, and then today all of a sudden it stopped working. Fourth blown transformer.

Although I haven't ruled it out completely, no one has admitted to tampering with the thermostat. I have done some more research and found that the switchover valve may be to blame. Needless to say...I would like to stop guessing and hopefully figure out what is really causing the problem.

Any assistance you can provide would be very helpful. I have pictures and will provide more component detail as necessary. Thank you in advance!!
 
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Old 05-14-09, 03:29 AM
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If you can post the wiring diagrams that would help. Fisrt question- what is the VA rating of the transformers? Second question- what voltage do you have at the transformer primary? 120, 208 or 240 volts? Make sure you are using the right tap on the transformer primary. Next time you have to replace a transformer, buy one that has a built in circuit breaker. A malfunction will trip the CB and prevent burnup. Next thing to do is investigate every inch of the low voltage cables. Don't miss any spots. Look for burn marks, chafing, etc. Flipping from one mode to another while the system is running shouldn't be causing the problem, however it is not a good idea. Next area to investigate is the supplemental heat section of the air handler. It could be you have a failed component in there and the failures are only showing up when the supplemental heat is on. Have you ohm tested the failed transformers? Which side failed? primary winding or secondary winding?

http://customer.honeywell.com/techli...0s/69-1014.pdf
 
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Old 05-14-09, 04:06 AM
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Though I applaud yor DIY attitude, after 4 transformers, a stat, a contactor, and a fan board its safe to say your in over your head.

Low voltage shorts can be tricky to find for an experienced tech, I would advise you call a good local HVAC company.
 
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Old 05-14-09, 11:36 AM
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Thanks for the prompt response! Tranfomers have all been 40VA. Primary voltage is 240, secondary 24. I'm not sure what you mean by using the correct tap on the primary. I'm guessing you mean the wire with the correct voltage. If so, I have.

Thanks for that suggestion...I will shop around for a transformer with a circuit breaker. The ones I've purchased are relatively inexpensive...about $10. It crossed my mind that "cheap" transformers might be part of the problem.

Checking every inch of cabling might be a problem, which is why I would like help in determining what wires to check/test for continuity and/or voltage. I have access to about a foot or so of wire at the air handler, thermostat, and outside unit. I will inspect those and post my findings along with the wiring diagrams shortly.

The system is a heat pump with supplemental heat...and the winter was so mild (TX) that the supplemental heat has not been necessary, so I'm not sure that the problem lies there (but I'm not dismissing it as a possibility since power to the transformer comes from there). And although I initially thought the switchover valve might be to blame, I now think something else might be the problem, since this last tranformer burned up on its own...without anyone tampering with the thermostat.

What I'm wondering is should I take the low voltage wiring apart at each unit and verify that none of the wires have somehow crossed or should I install the new tranformer and then test voltages after it is running? My guess is that the primary voltage is somehow bleeding into the secondary. How can I safely test that, without burning up another tranformer?

I have not tested which side failed, I will do that now and post back the findings along with the other items stated above.

Thanks again!!
 
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Old 05-14-09, 01:45 PM
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The primary voltage is not bleeding over. Usually, the primary side goes open and everyone wants to start looking for a problem on the primary side. However since both the primary and secondary experience the same load, the primary fries because it's made with smaller wire. Secondary current is 40va/24volts = about 1.67 amps. Primary current is 40va/240volts = about .167 amps. See why the prmary takes the hit? I suggest that with the power off you test the cables at each unit to the cabinets to see if you get a reading. Frankly I think you have a dead short which is why I would check the supplemental heat relay/contactor first. After that, start disconnecting compnents and see if it will run wthout popping a transformer. It can be frustrating. Check the wiring diagram n the outdoor unit to see f the switchover valve is 24 volts or 240 volts. Any chance you have a variable speed air handler?
 
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Old 05-14-09, 02:09 PM
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How old was this unit when it began problems 3 months ago?
 
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Old 05-14-09, 03:18 PM
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Mmead…The system has been in use since April 2003…worked fine until Feb or Mar of 2009. So it is a little less than 6 years old. It cools and heats like it should…

Daddyjohn…One thing I forgot to mention…with the last transformer I installed a fuse on both primary wires with the hopes that the fuse would go out before the transformer (replicating the fuse already on the secondary side). Unfortunately...it didn't help...the 10 amp fuse connected to the 240V lead burned up, but that didn’t prevent the transformer from burning up as well. The fuse on the common wire and the fuse on the secondary were both fine.

Also, I‘ve tested all the transformers for continuity and the primary side is open on all of them…the secondary circuit is closed on 3 out of 4 (it is also open on the transformer that was originally installed on the system-no clue why). So this supports your statement that the primary side is the one that normally takes the hit. Does this mean that the problem can in fact (more than likely at least) be attributed to a problem on the low voltage side?

You’ll have to excuse my lack of understanding…and also my repetitiveness…but I want to be absolutely sure I understand what you are saying.

That said…what do you mean by “I suggest that with the power off you test the cables at each unit to the cabinets to see if you get a reading.”? Are you saying I should check for continuity between the low voltage wires and the air handler and then do the same at the outside unit? In other words, check to see if they are grounded somewhere?

Also, what about… "Frankly I think you have a dead short which is why I would check the supplemental heat relay/contactor first.”? What is a dead short? And how do I check the relay/contactor?

Again, I apologize for not being familiar with the lingo and suggested procedures. BTW...I’m still working on inspecting the wires and posting the wiring diagrams…should be posted shortly.

Thanks for all your help.
 
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Old 05-14-09, 03:37 PM
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Yes look for a grounded wire. Dead short- what I mean is I think there is a component with a shorted magnetic coil or maybe a cable short. That would produce a short circuit across the transformer secondary winding. It's the same as if you had just run a wire from one side of the secondary winding to the other side. There would be no current comsuming device in between. Checking the cables means you're actually looking for the same thing- a short across the colors that go to the secondary winding. If you had a short say from the cooling wire color to the blower relay wire color that would just bypass the thermostat but not necessarily smoke a transformer. The 10 amp fuse you used was way too big to protect the primary winding.
 
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Old 05-14-09, 04:32 PM
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Thanks for the clarification...

Here is the wiring diagram for the supplemental heat unit.

http://farm4.static.flickr.com/3379/...62efb865_b.jpg

And a picture...

http://farm4.static.flickr.com/3585/...0babaedb_b.jpg

Others to follow...
 
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Old 05-14-09, 05:10 PM
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Could you post a pic of the transformer and a view showing wires coming into it and where they go once it leaves the transformer.

There really is 240 volts primary?, rather than 120? Is this common, DJ, in heatpumps, unlike that of typical split systems with furnace and a/c, that have 120?

When it went out that last time when you say that nobody fiddled with the thermostat -what mode was it in?; was it trying to heat at that time, or cool? Even if you think it may not even have been running at the time -for you to have noticed it went out, perhaps it was because you no longer got heat? or no longer got cooling?, so then you went and took alook? Or did you simply hear a noise or smell smoke and ran to the unit to check?
 
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Old 05-14-09, 05:16 PM
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Anybody think it might be a good idea to just pull all the low voltage wiring and put in fresh?
 
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Old 05-14-09, 06:28 PM
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ec- yeah the indoor section would be 240 volts because you need 240 for the strip heaters.

Elliot- try getting a resistance reading on the magnetic coil of the heat strip contactor. It looks ok but check it out- thanks. What's up with the ground wire in there? It should be landed at the ground lug.
 
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Old 05-14-09, 08:10 PM
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if you have all the burnt transformers are they cooked on the primary side or secondary sides..and what is the voltage on your 3-way valve on in the condenser..........you said you cooked the primary fuse but the secondary were ok check where you are getting the 240V for that TR primary might be spicking with the reversing valve energizing.maybe somebody here can say either a Trane 3-way is powered in heating or cooling mode.might also narrow it down seems to blow when you switch it to cooling from heat so i would go with slides to cool...that power to it is effecting the TR primary
 
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Old 05-14-09, 09:26 PM
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Here is the wiring diagram for the air handler...
http://farm3.static.flickr.com/2158/...f654963b_b.jpg

Here is a picture of the new transformer...
http://farm3.static.flickr.com/2046/...fcd61184_b.jpg

Here is a picture of the original transformer before I removed it...
http://farm3.static.flickr.com/2273/...83e02ef5_b.jpg

Here is a picture or the original thermostat and wiring...
http://farm4.static.flickr.com/3031/...8bf6a3c6_b.jpg

Here is a picture of the newly installed thermostat and wiring.
http://farm3.static.flickr.com/2323/...2229a9e6_b.jpg

Here is a picture of the reversing/switchover valve...
http://farm4.static.flickr.com/3376/...ba75431a_b.jpg

Here is a picture of the air handler prior to removing the 4th burnt transformer...
http://farm3.static.flickr.com/2416/...1588c3c4_b.jpg
 

Last edited by EliottIzzy; 05-14-09 at 10:33 PM. Reason: Added pictures
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Old 05-14-09, 09:46 PM
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Originally Posted by ecman51`
Could you post a pic of the transformer and a view showing wires coming into it and where they go once it leaves the transformer.

There really is 240 volts primary?, rather than 120? Is this common, DJ, in heatpumps, unlike that of typical split systems with furnace and a/c, that have 120?

When it went out that last time when you say that nobody fiddled with the thermostat -what mode was it in?; was it trying to heat at that time, or cool? Even if you think it may not even have been running at the time -for you to have noticed it went out, perhaps it was because you no longer got heat? or no longer got cooling?, so then you went and took alook? Or did you simply hear a noise or smell smoke and ran to the unit to check?

Ec..I posted a picture of the new transformer prior to it being installed and one of the original transformer prior to it being removed. Hopefully that shows what you're looking for.

The unit had been set to COOL for the last 2 months or so...it was working normally, then all of a sudden the house started warming up...so I went to go check the thermostat..sure enough according to the display the unit should have been in a cooling cycle...but the air handler and outside unit were both off. On the other hand...with the 3rd transfomer I happened to be right by the air handler when my wife switched from Heat to Cool...so I heard the noise and then was able to smell the smoke.
 
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Old 05-14-09, 09:51 PM
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Originally Posted by mmead
Anybody think it might be a good idea to just pull all the low voltage wiring and put in fresh?
The house itself is only 6 yrs old...and that sounds extremely difficult and expensive...I would like to avoid tearing up walls if at all possible.

But as a last resort...what does it entail and how expensive is it really? Any idea?
 
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Old 05-14-09, 10:26 PM
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Originally Posted by daddyjohn
ec- yeah the indoor section would be 240 volts because you need 240 for the strip heaters.

Elliot- try getting a resistance reading on the magnetic coil of the heat strip contactor. It looks ok but check it out- thanks. What's up with the ground wire in there? It should be landed at the ground lug.
Do you mean checking it for continuity from the blue wire to the white wire? I did...and there is continuity (circuit is closed). It should be closed right?

I'll fix that ground wire...I noticed it last time but did think much of it since it's been like that since we built the house.
 
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Old 05-14-09, 10:47 PM
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sorry
what I mean is remove the blue and white from the contactor and read the resistance of the magnetic coil in the contactor. Take the reading at the points where blue and white attach. One meter probe on where you removed blue, the other on where you removed white. You should get a measureable resistance.
 
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Old 05-14-09, 10:53 PM
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update- I looked at the AH wiring diagram, one side of the secondary is grounded to the cabinet. Hook up that equipment ground wire in the heat strip section pronto. It's possible that you're getting line voltage to the transformer secondary from a bad line voltage component. Have you ever felt a shock from the air handler?
 
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Old 05-14-09, 11:36 PM
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I loaned out my digital multimeter a while back and haven't asked for it back. All I have right now is an analog that shows zero ohms...ironically, I have a spare, but no clue where it is. I will obtain that reading for you tomorrow morning.

As far as that ground wire is concerned..it'll be #1 priority on my list tomorrow. I'm glad you you pointed it out...and to answer your question, I am happy to report that I have not felt shock from the air handler. Very happy about that! LOL

I also previously overlooked the following questions..."Check the wiring diagram n the outdoor unit to see f the switchover valve is 24 volts or 240 volts. Any chance you have a variable speed air handler?" According to the wiring diagram, the switchover valve solenoid is 24 volts. Also, according to the air handler wiring diagram...the air handler is capable of variable speeds, but was wired at a single speed. Let me know if you have any other questions.

Thanks again!
 

Last edited by EliottIzzy; 05-15-09 at 12:01 AM.
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Old 05-15-09, 06:18 AM
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Originally Posted by EliottIzzy
The unit had been set to COOL for the last 2 months or so...it was working normally, then all of a sudden the house started warming up...so I went to go check the thermostat..sure enough according to the display the unit should have been in a cooling cycle...but the air handler and outside unit were both off.
So auxillary electric heat was coming on in cooling mode?

Please stay with us on this thread until the end, as this is interesting.

..........................................

I erased center section of my original posting as my questions and thought process was answered after I studied photo of the new stat.
 

Last edited by ecman51; 05-15-09 at 06:44 AM.
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Old 05-15-09, 06:42 AM
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Originally Posted by EliottIzzy
Here is a picture of the newly installed thermostat and wiring.
http://farm3.static.flickr.com/2323/...2229a9e6_b.jpg
Why doesn't that new stat say "emergency" or "auxilary" on it also, if this really is a heat pump stat?

A rental I take care of has a heat pump and says "auxillary" on it. Also I just got back from a brand name thermsotat website, looking at photos of their stats, and their 'regular' digital stat looks like yours, but their heat pump version says "emergency" on it as well as the other things yours says.

If you have the wrong stat, maybe your furnace somehow kicks into emergency heat, without you knowing it, and then the transformer blows because you do not have the right stat?

................................................................

I just got off the phone with a Honeywell tech, as I was dying to know the answer to this after comparing their stats online to Lux stats, and their VisionPro 8320 series for heat pumps does not say emergency or auxillary on it. The tech said though that the function comes up on the screen when it is in auxillary heat mode.

So now my question is, did you even notice those words up on your display on your stat when the transformer blew? As I am fascinated by why heat was coming out when you did not have it in heat mode, and it was in cooling mode.
 

Last edited by ecman51; 05-15-09 at 07:40 AM. Reason: Added paragraphs below dots
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Old 05-15-09, 06:50 AM
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He says he's seeing open primary on the blown xformers. Woudn't this just be fatal recurring spikes in his house current?


quote..Also, I‘ve tested all the transformers for continuity and the primary side is open on all of them…the secondary circuit is closed on 3 out of 4

So I guess we're on to the question of what is causing the spikes?
 
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Old 05-15-09, 07:31 AM
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Why don't you have the black wire X2 hooked up to the new stat ?
 
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Old 05-15-09, 09:23 AM
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Originally Posted by ecman51`
So auxillary electric heat was coming on in cooling mode?

Please stay with us on this thread until the end, as this is interesting.

..........................................

I erased center section of my original posting as my questions and thought process was answered after I studied photo of the new stat.
My apologies for the misunderstanding...the unit did not simultaneoulsy try to heat and cool... what I meant by "the house started warming up" is that due to the unit being disabled by the dead tranformer, the temperature in the house started to rise...in other words, the AC unit should have been trying to cool, but it was dead.

I hope that makes sense...
 
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Old 05-15-09, 10:12 AM
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Originally Posted by ecman51`
Why doesn't that new stat say "emergency" or "auxilary" on it also, if this really is a heat pump stat?

A rental I take care of has a heat pump and says "auxillary" on it. Also I just got back from a brand name thermsotat website, looking at photos of their stats, and their 'regular' digital stat looks like yours, but their heat pump version says "emergency" on it as well as the other things yours says.

If you have the wrong stat, maybe your furnace somehow kicks into emergency heat, without you knowing it, and then the transformer blows because you do not have the right stat?

................................................................

I just got off the phone with a Honeywell tech, as I was dying to know the answer to this after comparing their stats online to Lux stats, and their VisionPro 8320 series for heat pumps does not say emergency or auxillary on it. The tech said though that the function comes up on the screen when it is in auxillary heat mode.

So now my question is, did you even notice those words up on your display on your stat when the transformer blew? As I am fascinated by why heat was coming out when you did not have it in heat mode, and it was in cooling mode.
The stat is a ritetemp 6030...I installed it based on the information on pages 20 (5 Wire Heat Pump w/ Aux Heat), 24, 25, and 26 in the manual...

http://www.ritetemp-thermostats.com/...tion_guide.pdf

I don't think that the auxillary heat is coming on...we can tell immediately when it does.

It has crossed my mind that it is possible that this particular stat is not fully compatible with my system, or that I may have installed it incorrectly, however, I don't necessarily think it is the culprit since the problems started before I installed it. Not to mention that the system had been operating "normally" until 2 days ago (as long as we didnt switchover from heat to cool or vice versa, while the system was running).

I hope that answers some questions...let me know if I left anything out.

Thanks!
 
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Old 05-15-09, 10:19 AM
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Originally Posted by mmead
He says he's seeing open primary on the blown xformers. Woudn't this just be fatal recurring spikes in his house current?


quote..Also, I‘ve tested all the transformers for continuity and the primary side is open on all of them…the secondary circuit is closed on 3 out of 4

So I guess we're on to the question of what is causing the spikes?
Is this possible? Wouldn't it fry other components as well? I don't know much about electrical, but isn't there some sort of regulator on meter?

One thing to keep in mind is that in two of the occassions I know for a fact that the spike occurred when the someone changed from heat to cool. Only this last time has no one fessed up to it, so the question remains...what is causing the spikes.
 
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Old 05-15-09, 12:31 PM
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"Thanks for that suggestion...I will shop around for a transformer with a circuit breaker."

DJ...I can't seem to find a transformer with a circuit breaker with a 40VA rating...Do you know if it is possible to use a higher VA rating safely? if so, I could use that Honeywell ATF150F you should me initially.

As a fallback option I am looking for a tranformer with the windings enclosed in metal (bell enclosure I believe it's called), however the one I found is at a shop unwilling to sell directly to a retail customer. I'll keep looking and maybe order online.

Thanks again.
 
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Old 05-15-09, 02:08 PM
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Yes, you can use a larger va rating, no problem. It just means that the transformer will have more wattage capacity. Concerning spikes- if the electrical system in the house were experiencing any voltage spikes, electronic items [computers. that expensive wall TV, etc.] would be dying long before the heat/cool system transformer would.

http://www.plumbingsupplies4less.com/transformer.php
 
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Old 05-15-09, 04:53 PM
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Originally Posted by daddyjohn
Flipping from one mode to another while the system is running shouldn't be causing the problem, however it is not a good idea.
I have been sitting here reading the lastest posts plus rereading all the posts. It sounds like the cause is the transformer blows when the mode is switched.

That said - Do heat pumps have some sort of delay device for safety of something that prevents an instant switchover?, perhaps to protect the compressor and line pressure? If there is such a device, then that device may not no longer be working, and that then would be the likely cause of the problem, I'd think.

If there is no such device to protect anything against this sudden changeover - nevermind.

Since the compressor and outside fan has to run for both heat and cool - and since it works for heat, that does not seem the area of concern regarding low or high voltage out there. It indeed sounds something related to the reversing. What other functions are employed by wires or on the control board when a person sets it to cool when the compressor and outside fan are already going in heat mode?: The reversing valve and ...what else? I mentioned a possible time delay device (if there is such a thing). Anthing else?

Any clues from a wiriung diagram? On newer heat pumps do they show separate diagrams for heat mode and cool mode for ease of following wires and components common to both, yet you can spot wires and components different for heat and cool?

If I was at Eliotts, I'd be camped out there until solving this problem. That is how I am. I'd take off work if I had to.
 
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Old 05-15-09, 05:42 PM
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"remove the blue and white from the contactor and read the resistance of the magnetic coil in the contactor. "

DJ...I got a reading of 11.2 ohms...does that sound right?

I've also hooked up that ground wire, made some minor repairs to the low voltage wiring on the outside unit (frayed wires), and tested each wire against the cabinets and each other for continuity. None of the wires were grounded or conducting electricity between each other, so I'm about to reassemble everything unless there is something else I need to test while the system is still apart.

Thanks!!
 
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Old 05-15-09, 05:46 PM
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Originally Posted by daddyjohn
Yes, you can use a larger va rating, no problem. It just means that the transformer will have more wattage capacity. Concerning spikes- if the electrical system in the house were experiencing any voltage spikes, electronic items [computers. that expensive wall TV, etc.] would be dying long before the heat/cool system transformer would.

http://www.plumbingsupplies4less.com/transformer.php
I wasnt able to find one of those in town...so I'm going to have to order it. For now, I've purchased one with plastic casings similar to the ones on the original transformer.

If possible, I would like some assistance after the system has been reassembled, testing for correct voltages, resistance, etc.

Thanks again DJ.
 
  #33  
Old 05-15-09, 05:56 PM
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Smile

Originally Posted by ecman51`
I have been sitting here reading the lastest posts plus rereading all the posts. It sounds like the cause is the transformer blows when the mode is switched.

That said - Do heat pumps have some sort of delay device for safety of something that prevents an instant switchover?, perhaps to protect the compressor and line pressure? If there is such a device, then that device may not no longer be working, and that then would be the likely cause of the problem, I'd think.

If there is no such device to protect anything against this sudden changeover - nevermind.

Since the compressor and outside fan has to run for both heat and cool - and since it works for heat, that does not seem the area of concern regarding low or high voltage out there. It indeed sounds something related to the reversing. What other functions are employed by wires or on the control board when a person sets it to cool when the compressor and outside fan are already going in heat mode?: The reversing valve and ...what else? I mentioned a possible time delay device (if there is such a thing). Anthing else?

Any clues from a wiriung diagram? On newer heat pumps do they show separate diagrams for heat mode and cool mode for ease of following wires and components common to both, yet you can spot wires and components different for heat and cool?

If I was at Eliotts, I'd be camped out there until solving this problem. That is how I am. I'd take off work if I had to.
I agree with you about the fault somehow pointing back to the reversing valve soleniod and a safety and/or control device. Perhaps the board on the outside unit? I've already replaced the fan relay board on the AH, so I don't think the problem lies there, but I guess it could...is there any way to test it, the reversing valve solenoid, and the board on the outside?

BTW, I appreciate your enthusiam! I am determined to find the issue...whatever it is. A few years back I completely took a part the wiring on a crown vic to find a fuel pump short...took me about a week, but I found it.
 
  #34  
Old 05-15-09, 05:57 PM
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unless it something different in HPs the discharge and suction run the same either in heating or cooling till the reversing valve changes the discharge directions to the COOLING...condenser or the HEATING...evap.sound like the reversing valve is powered in coolingTRY THIS run the cooling and access the condenser if you disconnect the wire on the solinoid it will Woosh over into the heating mode.NOW the test.... to see when you reapply it to Woosh it over to cooling..if the coil is 24Vs that draw and the lenght of the supply from the TR in the furnace might be doing it.
 
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Old 05-15-09, 06:14 PM
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Originally Posted by sminker
unless it something different in HPs the discharge and suction run the same either in heating or cooling till the reversing valve changes the discharge directions to the COOLING...condenser or the HEATING...evap.sound like the reversing valve is powered in coolingTRY THIS run the cooling and access the condenser if you disconnect the wire on the solinoid it will Woosh over into the heating mode.NOW the test.... to see when you reapply it to Woosh it over to cooling..if the coil is 24Vs that draw and the lenght of the supply from the TR in the furnace might be doing it.
Good idea but here's ymy peoblem with that:

You remember how Ricky Ricardo would say 'splain it to me Lucy"? Please splain to me how the RV could be blowing the transformer but not smoking the RV magnetic coil. Prolonged inrush current? It would smoke the RV magnetic coil. Low voltage? Why doesn't it smoke the RV coil or the compressor contactor coil?
 
  #36  
Old 05-15-09, 06:40 PM
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Lightbulb

I forgot to mention...I did get find continuity between the 16 guage yellow, orange, brown, and blue wires on the outside unit (after I had disconnected the 22 guage wires coming from inside the house)...if that mean anything. None between the black and red, or any of the others.

You can see them here prior to being disconnected.
http://farm3.static.flickr.com/2089/...cc85b8eb_b.jpg

As you can see, the green and white wires are not used, this is how the system was installed. Also according to the wiring instructions for the new stat, the BROWN(T) and BLACK(X2) are no longer needed. I reconnected them because that's how I found them...do you guys think I should have left those disconnected?

What about those same wires at the air handler...should I leave them disconnected there?

They are already taped off at the stat, so leaving them disconnected at the air handler shouldn't be a big deal...am I right? The BROWN does not tie into the air handler, it is simply connecting the stat to the "outdoor sensor". The BLACK (X2) wire on the other hand, ties into the WHITE (W2) wires, which according to pg 24 of the stat wiring instructions posted earlier, is the "heat pump auxillary heat".

You can see the BLACK and WHITE wires at the air handler here....
http://farm3.static.flickr.com/2352/...1a93c90a_b.jpg

Does that make sense? Anyone?

Thanks for your input!
 

Last edited by EliottIzzy; 05-15-09 at 07:18 PM.
  #37  
Old 05-16-09, 01:02 AM
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old stat you have the blue wire on B , new stat you have it on O
old stat the orange wire is on O I can't read the terminal letter on the new stat where the orange wire goes. I think X2 is Emerg Heat but don't remember for sure, but I can account for the function of all the other wires which why I think it's Emerg Heat.
You see the pattern?
Y-yellow wire W- white wire G- green wire Rh or Rc or R- red wire B- blue wire O- orange wire. Each color has a function which a protocol btw except Tranes protocol is a little different.
Take a close look at the old stat- notice that the upper glass bulb is clear while the bottom one is discolored? Notice the little color markings on the left side of each glass bulb? Red would be heat and blue would be cooling. Hmmm

In the AH, can you stand up the low voltage cable connections a little better so I can see exactly what wire goes where? Also, see that little envelope on the outdoor unit control box cover? The wiring diagram for the outdoor section should be in there. Can you post that and a shot of the controls in the outdoor section? Thanks.

I've been scoping out the photos a little better. In the one that shows the low voltage connections at the outdoor section, notice the two wires laying across the RV coil? The one on the left looks chafed or has damaged insulation. Hmmm
 

Last edited by daddyjohn; 05-16-09 at 01:40 AM. Reason: add text
  #38  
Old 05-16-09, 01:37 AM
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Originally Posted by daddyjohn
old stat you have the blue wire on B , new stat you have it on O
old stat the orange wire is on O I can't read the terminal letter on the new stat where the orange wire goes. I think X2 is Emerg Heat but don't remember for sure, but I can account for the function of all the other wires which why I think it's Emerg Heat.
You see the pattern?
Y-yellow wire W white wire G green wire Rh or Rc or R red wire B blue wire O orange wire
Take a close look at the old stat- notice that the upper glass bulb is clear while the bottom one is discolored? Notice the little color markings on the left side of each glass bulb? Red would be heat and blue would be cooling. Hmmm

In the AH, can you stand up the low voltage cable connections a little better so I can see exactly what wire goes where? Also, see that little envelope on the outdoor unit control box cover? The wiring diagram for the outdoor section should be in there. Can you post that and a shot of the controls in the outdoor section? Thanks.
Actually, the blue wire on the new stat is on C (as per the stat's installation instructions) and the orange wire is on O (although not visible in the picture).

Take a look at this info whenever you get a chance...it may clarify why the new stat is wired the way it is.

From a post by my earlier today..."The stat is a ritetemp 6030...I installed it based on the information on pages 20 (5 Wire Heat Pump w/ Aux Heat), 24, 25, and 26 in the manual...

http://www.ritetemp-thermostats.com/...tion_guide.pdf "

I will obtain and post the info you requested tomorrow morning.

Thanks for all your help DJ...I really appreciate it.
 

Last edited by EliottIzzy; 05-16-09 at 01:40 AM. Reason: Fix Hyperlink
  #39  
Old 05-16-09, 01:45 AM
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OK no problem the terminal under the blue wire kinda looks like an O not a C

btw- get an extra 40 va transformer [a cheapie, make sure it has multiple voltage primary wires] and get your meter back. We're going to make a little test.
 
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Old 05-16-09, 02:37 PM
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Originally Posted by EliottIzzy
BTW, I appreciate your enthusiam! I am determined to find the issue...whatever it is. A few years back I completely took a part the wiring on a crown vic to find a fuel pump short...took me about a week, but I found it.
You are my kind of guy. And I hope for your sake (and everyone trying to help here) the problem gets found and that your persistance pays off.

My persistance for a couple hours today is leaving me still panting while I type. I replaced all 3 toilet tank parts in a toilet tank for an old guy I know. And then one pin hole leak after another kept showing (at least some had to have been there before I started, but the leaking toilet masked the sound) up until I had my head stuck between the toilet and under the bathtub reaching way under there cobble fixing no less than 5 pin hole leaks!
 
 

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