Replacing basement heat pump

AFChap · 05-09-2016, 09:39 PM

Has anyone totally replaced their basement Coleman Mach ac/heat pump unit with a new one?

I think I am at that point. In the life of the coach (101k miles), I have spent apx $4,500 on repairs, apx $3k of that in the past four years. According to my records the inside blower motor has been replaced once, and the outside blower motor three times (including once in 2014 and once in 2015). The computer board has been replaced, and the #1 compressor was replaced in 2012. Now the #2 compressor is locked up (my diagnosis ...pretty obvious based on my experience with previous failures). The #1 compressor replacement and related repairs cost me $1,800 (and was not done well). I priced a new replacement unit today at $3k. I can't see paying almost $2k on another compressor when I will still have a 13 yr old unit, and $3k would buy a totally new one. I would install the new one myself ...I have little doubt I can do as good a job, and probably better, than any repair place I have ever taken it to with the exception of one in Andover KS.

Anybody else been here?

azpete · 05-10-2016, 10:09 AM

i have done several. the best thing you can have is a motorcycle jack from harbor freight., or some type of rolling platform. i use the motorcycle lift in case the unit has to come out the bottom.
the hardest part is getting the screws out of plenum on the rear of the unit. everything is straight forward.
my cell is 602-549-3638. ill be happy to help.
i do not solicit part sales or service on this site.

426smartin · 05-10-2016, 10:29 AM

Does the duct work on the replacement need to be modifed or is is "plug and play"

AFChap · 05-10-2016, 12:38 PM

No problem w/getting it out. I have a hydraulic cart that makes it pretty easy. Just wondering if anyone has done a complete replacement rather than repair ...either themselves or had it done. According to the mfg'er, the new model 46515-811 would be the replacement for my model 6535A871. The pictures and manuals I have looked at look identical in terms of physical appearance, duct location, etc. Mfg'er apparently doesn't sell direct as guy I emailed with said they could not give me a price ...said I would have to get that from "local service center."

LookAtUSNow · 05-10-2016, 04:51 PM

I replaced mine recently. An HVAC guy and looked at and told me the same story that you described. I could spend money repairing it or just replace it and be done.
The unit was 15 years old, and I felt like it had served its lifespan well.
I opted to replace it, I could have done the job myself but did not have the comfort level hooking up the new unit.
Two men lifted it out and put the new one in, no special tools to lift or install required.
The unit was pretty much an exact fit except for the return didn't line up the way I would have expected, but it was close enough to work properly.
I didn't like the method used to seal the spaces, so I actually slid the unit back out and retaped and used foam rubber to seal the intake.

No regrets and we have AC and heat.

tomsm · 05-10-2016, 07:07 PM

Paul, please keep us advised. My unit has been flawless, but it is ~13 years old. I'm thinking, when the first thing fails, I'm going the way you're going. Cause I'm guessing, when that first part fails, it's going to be the 1st of many failures.

Getting 13 years at $0 expense makes a $3K replacement seem quite reasonable.

Good luck with yours!

LookAtUSNow · 05-11-2016, 07:37 AM

If you do decide to DIY, repost, there is a different set up for the new model wiring, I can send a pic of mine if needed.

Heating man · 05-11-2016, 06:03 PM

Quote:

Originally Posted by LookAtUSNow

If you do decide to DIY, repost, there is a different set up for the new model wiring, I can send a pic of mine if needed.

why does it wire differently and do they tell you how to wire it and does the thermostat need to be changed. any difference in operation?

LookAtUSNow · 05-11-2016, 08:41 PM

If I recall correctly there was one or two odd wires that hooked differently. Something about the new controller set up on the box. You mentioned you replaced the controll box, so you may/should have the same setup. I never upgraded so it had the original setup. The repair guy called Coleman and the tech told him where to connect the wires. It operates the same, only better because it's newer some of the added noises are gone as opposed to the old unit. Thermostat is the same and functions the same.