Log In | Register
Skip to main content
Topic: Dometic heat pump wiring burned up (Read 586 times) previous topic - next topic
0 Members and 6 Guests are viewing this topic.
Dometic heat pump wiring burned up
Hi folks

Need your help and advice. We have a 2013 TK 24ft which we picked up at the mothership in Feb 2014. We thought "oh boy...worry free camping for a good long while"....

 Imagine our shock when we were out camping last week and our AC (heat pump) failed to operate after a few days. Fortunately for us, the weather was mild (which is unusual) so we were okay without AC.

Upon returning home, DH got up on the roof and examined our 3 year old AC and found that a wire inside the AC was completely burned! WHAT???  We had our old SOB for 15 yrs  (with two Coleman AC) and never had a lick of trouble out of them!

Of course the warranty expires at two years. And we have found extended warranties to be a waste of time and money as experience has been that whatever breaks is never covered by our extended warranty...consequently we do not have it for the AC.

Our question to you tech gurus is what caused the wire to overheat. DH says it is the white wire where it attaches to the compressor with a bayonet fitting  that burned up. Any ideas on what caused it to burn?

I will post pictures if I can figure out how to do it :)

Thanks in advance!
Corky
2013 TK
Re: Dometic heat pump wiring burned up
Reply #1 –
Hello Corky ... not very good news from your part of the LD world.  So sorry to hear about your trouble.  I found the following post in another forum that sounds very much like your situation.

Burnt electical smell from AC

Folks mentioned a loose connection, a bad capacitor, and low voltage (shore power).  In this particular case, it was a loose wire.
Dometic AC wiring problem pictures
Reply #2 –
Sorry this is the only way I could see how to post the pictures of the Dometic AC wiring problem.  See my other post to read the story.  Look for the white wire in the photo..that is the one that burned.

Thanks
Corky
2013 TK
Re: Dometic heat pump wiring burned up
Reply #3 –
Thanks we will check it out.

Corky
2013 TK
Re: Dometic heat pump wiring burned up
Reply #4 –
Quote from: corkydeltadog  - 
Hi folks

Need your help and advice. We have a 2013 TK 24ft which we picked up at the mothership in Feb 2014. We thought "oh boy...worry free camping for a good long while"....

Well, at least you got three years. Our AC failed the second day of our maiden voyage in our then-new 2006 TK.  In Vegas. In 105 degree weather. No one would even look at it within a week. With reservations at Zion and beyond, we just pressed on for the balance of our 7 week trip. Turned out a be a notoriously flimsy start capacitor. Had it repaired and working fine ever since.  You have my sympathies. This is a Dometic problem, not Lazy Daze's. -- Jon
(Former) ‘06 TK “Albatross.” And (former) Vespa 250.   Alas, no more; both are gone.😕 Great memories remain! 😄
Re: Dometic heat pump wiring burned up
Reply #5 –
[quote author=Jon & Loni link=msg=170840 date=1490285808
 Our AC failed the second day of our maiden voyage in our then-new 2006 TK.  In Vegas. In 105 degree weather. No one would even look at it within a week. With reservations at Zion and beyond, we just pressed on for the balance of our 7 week trip.
[/quote]

Reminds me of a trip my son and I made from the Central Coast to Lake Mead, Zion, Bryce, etc. in 2000. The '85 had a swamp cooler and broken cab AC.  This was in July. I still remember pulling into Baker, Ca for a lunch stop and looking at the "Big Thermometer" which read 115 degrees! No worries, we were on an adventure!
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264
Re: Dometic heat pump wiring burned up
Reply #6 –
Adventures:
My adventurous son took a $3000 barely seaworthy POS sailboat on an 18 month journey down the coast of Baja and into the Sea of Cortez, accompanied only by his dog.   No radar, electronic navigation, water maker, marine head, life raft, ... you get the idea.  His reply to my discomfort with his planning and preparation was "Dad, being dangerous, unpredictable, and uncomfortable is what makes it an adventure."

115 in Baker in July with no AC would definitely qualify.
2014 27 MB
Towd: Either the Jeep Wrangler or trailer containing the BMW R1200GS and 2 E-bicycles
Happy wife=Happy life
Re: Dometic heat pump wiring burned up
Reply #7 –
Hi all,

My complaint is NOT with Lazy Daze...my complaint is with Dometic A/C.  As I previously stated earlier  our old SOB AC (Coleman) lasted 15 yrs, never a problem, and was working fine when we sold the unit back in 2014.  I fully expect  the LD to last a good long while, but the appliances are not as dependable (no fault of Lazy Daze) and they lack the dedication to making a quality product like Lazy Daze does.

My original question to you all is what do you think caused the wire to burn up? Traxless gave a link and I am thinking he is right about the cause of the failure being a loose wire. From what I have gathered elsewhere on the web, Dometic products are not durable and being that they are made in China kind of explains the shoddy workmanship and inferior materials.  A loose wire can cause an overload in the amps and overheating is the result. Any others theories as to the failure of the wiring are welcome to submit.

Meanwhile DH is pursuing options to make the repair and then keep a sharp eye on it. If complete failure of the unit occurs, we will be exploring other options rather than just sticking another Dometic in there. 

Thanks Traxless for the link and info..it was helpful!

Corky

2013 TK
Re: Dometic heat pump wiring burned up
Reply #8 –
"DH says it is the white wire where it attaches to the compressor with a bayonet fitting  that burned up."

I just want to make sure I understand the type of connector. When you say "bayonet connector" is this what you are referring to?
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264
Re: Dometic heat pump wiring burned up
Reply #9 –
Quote from: corkydeltadog  - 
Meanwhile DH is pursuing options to make the repair and then keep a sharp eye on it. If complete failure of the unit occurs, we will be exploring other options rather than just sticking another Dometic in there. 

While we really enjoy and appreciate the quality of our LD, our major wish is for the AC to be quieter.  Living in a place with high temperatures many months of the year means camping in heat or camping with a loud AC running hours a day.  And we like quiet.

So from time to time, I've searched for AC technology updates and improvements.  One of the promising AC units is made by Atwood.  http://www.askforatwood.com/air-conditioners/rv-air-conditioners.asp  There is an interesting story about the Pro's and Con's of the Atwood AC at Atwood vs Dometic .  If I remember correctly, this unit was originally designed in Australia and is a popular AC unit.  Sadly it has at least one (1) major drawback for us and that's the fan runs all the time unless manually turned off.

Even though our Dometic AC is working fine except for being louder than we'd like, I'd sure be tempted to replace it with a quieter unit.  But so far, I haven't found a quieter AC.


Re: Dometic heat pump wiring burned up
Reply #10 –
Well, the quickest way to find out is to replace the burnt wire and plug, then seeing if the compressor still runs or if it is frozen up.
It cannot be taken apart for inspection.

It usually isn't cost effective to repair a bad compressor. These A/Cs, like the refrigerators, are built about as cheap as they can make them.
Dometic is definitely on a race to the bottom, along with Coleman.

When our LD was new, the A/C stopped working on the first hot day it was used.
I used so many vacation hours, going back and forth to the "Authorized" Domestic shop, that it would have been cheaper to buy a roof A/C and to have  forgotten about the warranty.
The thing that really upset me was I had already determined that the problem was a bad over-temp switch and the offer to buy it outright was denied because 'it's under warranty'.
The switch was an off the shelf switch, stamped with a proprietary part number which could not be cross indexed.
The first day I went to the cross town shop was cool and the A/C would not cut out, requiring second trip to verify the problem and then, after waiting several days for authorization, I made the third trip to replace the switch.
In the RV business, warranties are just about worthless unless you have a lot a extra time to spend.
Even LD limits what they consider to be a 'warranty' problem.

I know Steve is frustrated with the quality of RV accessories, it seems to be impossible to find high quality RV appliances.

Larry

Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Dometic heat pump wiring burned up
Reply #11 –
Hi again,


Here is a photo of the wire and connector up close. Sorry it is a tiny piece that causes so much havoc.   Yeah the plan is to replace the wire and connector and see what happens!
2013 TK
Re: Dometic heat pump wiring burned up
Reply #12 –
Hey Traxless

 we are definitely with you on that loudness factor but enjoy our "cool"...I don't remember our old SOB being that loud but it also was a ducted system...maybe that had something to do with it...
2013 TK
Re: Dometic heat pump wiring burned up
Reply #13 –
Hey Larry,

Yeah, warranty work in a real pain! We got an extended warranty on our old SOB and found it to be a waste of time and money.

One example was when the parking brake got clamped to the drive shaft because it had a hydraulic system that clamped it to the drive shaft to park it.  Well, a cheap little switch made of plastic broke and the whole thing got stuck in park and couldn't go anywhere.  A thousand dollars later we could move again...the warranty claim was denied...why?  Cuz they don't cover "that kind of parking brake." Huh??? Well it's only one we got and it says right here on your paper that it covers 'the parking brake'...no dice. Lesson learned.  So that's why we don't have an extended warranty on this AC unit.  As you say..cheaper to write the check than argue with them!
2013 TK
Re: Dometic heat pump wiring burned up
Reply #14 –
Quote from: corkydeltadog  - 
Hi again,


Here is a photo of the wire and connector up close. Sorry it is a tiny piece that causes so much havoc.   Yeah the plan is to replace the wire and connector and see what happens!

For clarification purposes, that is a type of spade (blade) connector. They do tend to work loose at times.

http://www.oreillyauto.com/site/c/search/Wire+Connectors+-+Spade+Style/N0214/C0189.oap
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264
Re: Dometic heat pump wiring burned up
Reply #15 –
Any time I'm installing a spade type connector I use a pair of long-nose pliers and crimp the edges of the connector so that it's a force fit on it's mating part. The Air Force taught me that!  :)
Steve S.
Lazy Bones & Cedar
2004 30'IB (Island Bed)
Yesterday is History, Tomorrow is a Mystery
Live for the day!
Re: Dometic heat pump wiring burned up
Reply #16 –
Hi Lazy Bones (Love that name!) and Hilola,

Thanks for the clarification.  Yeah I followed the link and see the part costs $3.50!  What an irony that that little piece could destroy a thousand dollar AC. Yikes!  

At this point DH plans to solder the wire on to prevent it coming loose again.  Here's hoping the fix works and the compressor kicks on again. 

Thanks for your help!

Corky
2013 TK 24
2013 TK
 
Re: Dometic heat pump wiring burned up
Reply #17 –
"Our question to you tech gurus is what caused the wire to overheat?"

And, the answer is, plain and simple, the wire was carrying more current than it was designed to do! But the wire is not your culprit and you need to look for another cause. That's not to say that the terminal connections were faultless, they could have been loose, offering a higher resistance than normal. And it could have been a one time event... only replacement of the wire and testing will answer that. Worse case scenario would be a bad compressor. You could use a larger gauge wire but that would be comparable to using an over size fuse, not good.

And you've got to ask yourself what the conditions were when it all hit the fan. Did you have the settings on the A/C at two clicks above maxx, or a medium (normal) setting? I've had my unit freeze up if I try to push it too far.

The next step I would do is to use a wire brush or fine emery cloth and burnish the terminals where both ends of the new wire will go. An added step would be to coat those connections with a dielectric grease, such as Cramolin R-5. Don't go Godzilla on it but make sure the connections are quite snug. Let us know how it turns out!  ;)
Steve S.
Lazy Bones & Cedar
2004 30'IB (Island Bed)
Yesterday is History, Tomorrow is a Mystery
Live for the day!
Re: Dometic heat pump wiring burned up
Reply #18 –

"Any time I'm installing a spade type connector I use a pair of long-nose pliers and crimp the edges of the connector so that it's a force fit on it's mating part. The Air Force taught me that! " 

Agreed, and once on, tug gently, try to rock it back and forth on the terminal to confirm NO movement.  If there is, I start over.  And, always check the others at the same time for any movement or discoloration.

"That's not to say that the terminal connections were faultless, they could have been loose, offering a higher resistance than normal. And it could have been a one time event... only replacement of the wire and testing will answer that." 

This is where my money is, seen it many times!  Looking at the original pictures, the spade on the red wire is discolored, and should be re-done too.  In addition to that, the terminal connector on black wire is the type normally used on compressors, (note there is more 'meat' to the connector, and that the two edges (for lack of a better term) can be squeezed together to allow a better purchase on the terminal post on the compressor), while the other two are regular spade connectors...hmm, why is that? 

I think the compressor will be fine, but if not, it's more likely it would be the victim rather than the culprit.

Here's a link to a compressor terminal similar to what's on the black wire.  Any refrigeration\AC wholesaler would have these in a bag, or any friendly HVAC contractor could likely be convinced to sell a couple. 

Amazon.com: Diversitech CC32 Compressor Terminal, 1/4, (3 Pack): Home...

If the burnt terminal on the compressor has been damaged enough to where it is difficult to get a good connection with a regular compressor terminal, if it can be even temporarily connected to prove the compressor is okay, here's a link to a more permanent solution, not cheap, but appears to be good (I like something I can tighten down).
There are some others that are less expensive, but check the wire size...no need for anything larger than #12.

Amazon.com: JS-Tecumseh QT2912 Qwiklug Compressor Terminal Repair Kit: Home...

As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
Bill
2003 -- 23' FL
Re: Dometic heat pump wiring burned up
Reply #19 –
Quote from: Traxless  - 
While we really enjoy and appreciate the quality of our LD, our major wish is for the AC to be quieter.  Living in a place with high temperatures many months of the year means camping in heat or camping with a loud AC running hours a day.  And we like quiet.

We manage the noise problem by doing the majority of our cooling with a TurboKool evaporative cooler. The A/C gets used much less often, though always in 100+ temps, and some in 90+ temps, where shading and breeze might make the TurboKool adequate. It's so much quieter than the A/C, especially if we have to run the generator,
2005 Jayco 24SS
Re: Dometic heat pump wiring burned up
Reply #20 –
Quote from: Lazy Bones  - 
"Our question to you tech gurus is what caused the wire to overheat?"

And, the answer is, plain and simple, the wire was carrying more current than it was designed to do! But the wire is not your culprit and you need to look for another cause. That's not to say that the terminal connections were faultless, they could have been loose, offering a higher resistance than normal. And it could have been a one time event... only replacement of the wire and testing will answer that. Worse case scenario would be a bad compressor. You could use a larger gauge wire but that would be comparable to using an over size fuse, not good.

And you've got to ask yourself what the conditions were when it all hit the fan. Did you have the settings on the A/C at two clicks above maxx, or a medium (normal) setting? I've had my unit freeze up if I try to push it too far.

The next step I would do is to use a wire brush or fine emery cloth and burnish the terminals where both ends of the new wire will go. An added step would be to coat those connections with a dielectric grease, such as Cramolin R-5. Don't go Godzilla on it but make sure the connections are quite snug. Let us know how it turns out!  ;)


Hi Lazy Bones,

Actually we had it on heat since the weather was a little chilly at night (mid 40's) and we heard it shut off and it was going through its defrost cycle.  We got up and shut it off and switched to our little electric space heater.

The next day, it was in the mid to upper 80's, so we tried to run the AC...the fan works but not the AC compressor. That's when we shut it all off and got by with open windows and fantastic fans.

Thanks for the suggestion of the dielectric grease. We will work on repairs and report the results.

Thanks again

Corky
2013 TK
Re: Dometic heat pump wiring burned up
Reply #21 –
Quote from: krmugn  - 
"Any time I'm installing a spade type connector I use a pair of long-nose pliers and crimp the edges of the connector so that it's a force fit on it's mating part. The Air Force taught me that! " 

Agreed, and once on, tug gently, try to rock it back and forth on the terminal to confirm NO movement.  If there is, I start over.  And, always check the others at the same time for any movement or discoloration.

"That's not to say that the terminal connections were faultless, they could have been loose, offering a higher resistance than normal. And it could have been a one time event... only replacement of the wire and testing will answer that." 

This is where my money is, seen it many times!  Looking at the original pictures, the spade on the red wire is discolored, and should be re-done too.  In addition to that, the terminal connector on black wire is the type normally used on compressors, (note there is more 'meat' to the connector, and that the two edges (for lack of a better term) can be squeezed together to allow a better purchase on the terminal post on the compressor), while the other two are regular spade connectors...hmm, why is that? 

I think the compressor will be fine, but if not, it's more likely it would be the victim rather than the culprit.

Here's a link to a compressor terminal similar to what's on the black wire.  Any refrigeration\AC wholesaler would have these in a bag, or any friendly HVAC contractor could likely be convinced to sell a couple. 

Amazon.com: Diversitech CC32 Compressor Terminal, 1/4, (3 Pack): Home...

If the burnt terminal on the compressor has been damaged enough to where it is difficult to get a good connection with a regular compressor terminal, if it can be even temporarily connected to prove the compressor is okay, here's a link to a more permanent solution, not cheap, but appears to be good (I like something I can tighten down).
There are some others that are less expensive, but check the wire size...no need for anything larger than #12.

Amazon.com: JS-Tecumseh QT2912 Qwiklug Compressor Terminal Repair Kit: Home...




Thanks for the suggestions and link.  DH says he plans to replace the wires and solder them to be sure they stay connected.  I am hoping you are right and that the compressor is intact.  That would be a bummer to replace the AC unit...UGH! We will report back with results when DH makes the repairs.

Thanks
Corky
As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
2013 TK
Re: Dometic heat pump wiring burned up
Reply #22 –
Quote from: corkydeltadog  - 

Thanks for the suggestions and link.  DH says he plans to replace the wires and solder them to be sure they stay connected.  I am hoping you are right and that the compressor is intact.  That would be a bummer to replace the AC unit...UGH! We will report back with results when DH makes the repairs.

Thanks
Corky


If accessible, to me it makes good sense to solder the connections.  After all, how often does the AC need to be disconnected anyway?  However, you may want to ensure the unit is not fried first!

As some like to say YMMV!
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264
Re: Dometic heat pump wiring burned up
Reply #23 –
ATTN:  Corky

I'd like to thank you for taking the time to bring up this rather important topic, despite your lousy "luck."  So if it's any comfort, you've helped us to be a bit more knowledgeable about our AC wiring.  Now I'm going to climb upstairs and check that wiring which is something I'd not thought about.  In fact, I don't remember this item on any of the many Preventive Maintenance Schedules or lists that I've reviewed this last year or so.  Nevertheless, it's on our PM Schedule now!

Take care.
Re: Dometic heat pump wiring burned up
Reply #24 –
"If accessible, to me it makes good sense to solder the connections"

I respectfully disagree.  If it were a good idea, compressor manufacturers would do it in their own best interest, but never have AFAIK.

IMHO, getting a couple of the proper spade terminals, crimping them carefully, and then confirming they are tight on the compressor terminal with the same care will likely put this problem to rest for many years. 

 
Bill
2003 -- 23' FL