Trane Heat Pump System Fusible Links and Heater Strips

[bobvj]

My heat pump does ok in summer and warm winter days. Lately though it's a losing battle at night. I have a split air handler in my attic. I think the problem is with the heating strips.

Even when I put the thermostat on Emergency Heat, there's almost no heat coming out. I opened the air handler and ran continuity checks across the three heating strips and fusible links. Only 1 heating strip showed continuity, and none of the fusible links did. I pulled two of the links out. They have a ceramic tear drop base. Physically they looked fine, but I could not get continuity. Do these visibly melt when overheated, or is there something inside the cone shaped connector? The connector has a reddish/orange tip.

The unit is about 12 years old.

Model is TWH036B1401.

I appreciate any insight.

[karsthuntr]

No you cannot look at it and see if it is bad.

Please call a contractor out to evalute your system and repair it for you. There is a reason the fusible links are open. This could cause a fire in your air handler.

Please Read Site Rules (http://hvac-talk.com/vbb/showthread.php?threadid=1241)

[duc dowg]

why do these people try this there self

[bobvj]

Thanks for your informative replies.

I'm not going to be doing this myself, but being a professional engineer I am interested in how things work. Unfortunately I did not take the time last year to understand the problem when I called an HVAC repair company to look at it. They said the freon charge was ok and left it at that. It was part of the warranty I got when buying my "previously owned" home. After suffering through the winter and now having it start again I've decided to get smart about things.

I've got an appointment on Tuesday with a company of my choosing and I intend to ask many questions. I also intend to have the work professionally done.

[aircooled53]

Trane Fuse Link Holder~00620~CNTO1068
But , as stated there is a reason for this link to have shorted...

[bobvj]

I had a contractor come and look at the unit. He confirmed that 2 of 3 heating elements are not working. He tried to order a replacement heater package. The original was BAY96X1411. The Trane air handler is TWH036B140A1 . Contractor tried to order parts but says no luck. Suggests that I get the heater assembly rebuilt by a local company. But, he doesn't have an account with them, so I'd have to remove the unit myself (which I am able and willing to do) and then he can reinstall for me. Since one heater element is working fine, I'm ok til spring and can do it then.

I then called a Trane rep and asked about replacement for the heater assembly and having him install it. He stated they no longer make it, you have to replace the entire air handler for big $$. Since the air handler is in my attic there are big labor costs in addition to the price of the air handler.

So I need to know is there a way to buy the entire heater assembly BAY96X1411? If not, do companies rebuild these items to OEM specs? I can't believe that I'd have to replace a perfectly fine air handler just because 2 strips in the heater package are bad.

[cde72]

Okay... call another company, no company I know would tell a homeowner to do anything under the "hood"... The heaters can be rebuilt, but no, they will not be OEM, and no, they will not last long from my expierence...

[docholiday]

I suppose if your still in love with your air handler you could add a duct mounted heater in the supply but that wouldnt be my first option.

I dont know what the heater you refer to looks like off hand but if they are typical 5kw heaters that look like big springs, having it restrung is not difficult. Sure Trane would love for you to replace the whole thing but your technician appears to be less than compitent if he cant restring a heater package if its a standard heater. And worse yet he said you would have to pull it. Somewhere, a little red flag should have jumped out at you.

I'll have to leave it to one of the Trane gurus to tell me if your heater strips are standard. If they are cal rods, then the guy from Trane might just be telling you like it is.

If infact they are "big springs" you would know if one was blown by looking at it, it would be broke, the fusible link on the otherhand needs to be examined using a meter as you said. Frankly if your elements are burnt and the fuse plugs are bad, they you have an airflow issue which will likely come back and destroy the next set too if not resolved.

[bobvj]

I need to add some details, so as not to have the 1st contractor look bad. I thought him to be very competent and helpful.

Yes, all 3 fusible links were bad. 2 of 3 heating strips were bad. He replaced the one link for the one good strip. He never physically removed the heater assembly, but he assumes it is the coil type heaters. He says that he's had limited success in the past with re-stringing. Lot's of money for him and not sure if the new coils are ever properly adjusted for carrying the design loads. There are 3 coils, two at 2.88KW and the third at 4.8KW or thereabouts. He took down model numbers and went back to headquarters to order the replacement heater assembly. We both believe that the original failures were due to airflow blockage at some time in the past before I bought the house. I've been very conscientious about replacing filters on the intake plenums in each room.

A week later he says his HQ ordered an assembly but he didn't think it looked right. He came out and sure enough it wouldn't fit without him basically cutting the new one in half. At that point he suggested that I get the unit rebuilt by a local company. Since it's still winter, and since I now have 1 strip working, the system has been holding temp even on cold nights. I don't want to remove the assembly until the heating season is done with. He saw that I was rather competent about the unit and suggested that I could remove the unit myself in the spring and then call him to have it professionally reinstalled after it's rebuilt. His company doesn't have an account with the rebuild company but thinks that I can have them do it for me.

So, his preference was to buy the factory fresh heater assembly to replace the old. His next was to have it rebuilt by a local company. His least favorite was to restring it himself.

I really take issue with the subsequent discussion with a local Trane distributor whose only response is that the heater is unrepairable so you have to replace the entire unit. And while you're at it, replace the outside heat pump at the same time.

So, I'm trying to verify that it is impossible to buy a factory fresh, or even rebuilt, direct replacement for the heater assembly package. If that's the case, then I'll try the local rebuild route. Barring that, I'll call the first guy back and ask him to re-string.

[Edited by bobvj on 02-02-2005 at 01:51 PM]

[docholiday]

The reason Trane said that, and I was jesting, is because if it is not restrung using all the proper parts and a house catches fire, somehow they will end up in a lawsuit and you know this to be true.

I dont know how old the unit is or anything about it. Bottom line is after 10 years or so after production of a model ends, manufactures arent obligated to continue to build replacement parts. In some cases it is within their interest to do so but not likely. No you cannot go buy a factory right front fender to a 1987 chevrolet chevette. They just dont make them anymore.

I have, on the otherhand had good luck with restrings. Probably because I verified airflow, wiring, voltage etc. To me, a wire with the proper resisntce and correct metal to make the right KW heater is pretty simple and there is not much difference from OEM. In general its, as I say an airflow issue (not always filter related) or the restring was not properly done. If you have the coils unevenly pulled, will likely burn it out where it is buched together. Watt density is a real thing that is difficult at best to explain let alone understand.

[BaldLoonie]

We have a similar situation. Was told today that the BAYHTRs from Trane will fit the older air handlers that had the BAY96X kits. Haven't gone back to confirm the advice yet but that's what the supplier said.

[jrbenny]

I wouldn't use the new heaters in old air handlers. The problem is lack of UL rating for the BAYHTR kits in the old air handlers that took the BAY96X. If a fire occurs, it's your butt in a sling.

Have it restrung or get a new air handler.