Heat Pump Compressor Dead; Need Advice on Replacement System

Fellas, I think there are several of you on this board who work in HVAC, or have, and the rest have lots of practical experience with your own systems. I need your help.

Our heat pump, which as I recall is about 16-18 years old, died last week during the extreme cold spell. Switched it over to emergency backup heat (electric resistance coils) and that's working fine since I'd just fired up the DS 1500 two days earlier. Electric isn't running much, even during the extreme cold last week.

The house is a two-story colonial, about 2250 sf heated and cooled; we have 700 more sf in basement rec/TV room which gets plenty of heat from the stove when it's on, plus a couple small electric baseboard units we only turn on while we're watching TV when the coal stove isn't on. The house is 30 years old and it isn't tightest house around--that's one of my major projects the next year or two.

Over the past year, I've looked into new heat pump systems with a propane furnace as backup (or primary for winter). We have no natural gas service in our area.

My heating and plumbing guy, who I've used for 25 years and is very conscientious, came over today and confirmed the HP compressor is seized. I told him whatever we do as a replacement system I want to keep the hood over the coal stove connected into the return side so the heat from the stove is distributed through the house.

He's concerned with the new hi-tech HP systems with the fancy new freon, drawing in the extra warm stove air will raise the freon pressure and trip the hi-pressure safety switches that are built into the new-fangled units. He's gonna contact Rheem about that and see if they have any ideas.

But he's also talking about just replacing the HP altogether with a propane furnace and a central air conditioner. Have to figure out where to put some pretty hefty tanks if we do that. As long as I'm still burning coal, fuel cost will be minimal--in fact my guy said I might actually see lower heating costs overall, since I won't be trying to run the HP compressor all the time and the backup heat part-time during the coldest part of the winter. But I'm concerned about being totally dependent on propane when I want/have to hang up my coal shovel.

All things considered, I've liked the HP for nine months a year--very efficient cooling, and heating in the shoulder months. But I've read about issues with the new HP technology.

My guy is urging me to take my time and check out options. He says we should be ok with the coal stove and the electric emergency heat, even till spring if we want. Our only risks are losing the blower motor or heating coils and those would be quickly fixable.

Anyone's thoughts, experiences, advice will be appreciated on new heat pump vs. propane (or other options...oil?) furnace, and keeping the coal stove tied into the system. Thanks!

One thing that is needed to weigh into all this is your age. When you need to quit shoveling coal will you still want to live in this big of a house ? How many yrs do you have till you hang up the shovel ?I would look into a more automated coal system & personally at age 57 ,that is something I may do in 15-20 yrs. A furnace or boiler with an automated loading system could do all the work for you,even an ash removal system so your input would need to be very little.You are smart to take some considerable time to weigh your options ,for sure.

Off the cuff, how about ductless mini-splits for HP and use existing duct for coal and propain.

I would also strongly urge you to consider the mini-split heat pumps that can support up to 4 indoor units each. Many are good down to -5 degrees at full heat rating. No duct loss means super high efficiency. Easy to install and reasonably priced (or should be if your installer is familiar with them). I know of one working very well in Oley, Pa right now.

Technology has helped improve HP's all along, but this inverter motor feature really takes them far as for efficency.

Guys, thanks for the ideas.

WindyHill, I'll be 59 in December, and pretty good healthwise, so I hope to be able to enjoy maintaining this house, and the stove, for another 5-10 years. Although I'm starting to feel some worrisome twinges in the knees now and then.

I'll certainly look at an auto-feed coal option.

tjn and McGiever, my HVAC recommended a ductless system about a year ago for my basement room, but didn't say anything about ductless mini-split. I'll check it out--I like the idea of separating that out of the duct and leaving the duct system for coal/propane.

I'll probably be back with questions later...thanks again!

If your happy with how your existing system has worked, why not just get a new compressor installed? If the coil is still in good shape, I believe you can still order just about any Freon type compressor, and the HVAC guy may not like it because it's a more miserable job but it gets you back on the road with a system you were happy with.

Mark, I feel your pain. My compressor went south early this month. Replaced at $2500.00 and lit the Harman about 2 days after the install. Central unit has not come on since I lit our stove. Oh well its ready for summer.
C.

I am employed in the HVAC industry so hopefully the info I give can help you a bit. If you are happy with how the heat pump has served you over its life, I would recommend replacement of the complete system. Some of the newer variable speed equipment is very efficient at lower temperatures. Ask about variable compressor technology if you are getting a quote. I would hesitate to rely on propane at my house, just because of the availability issue that occurred last winter.

I also install MItsubishi ductless systems and they are very efficient and I wouldn't hesitate to put them in my house. If you are possibly going to rely on them for your only heating source ask about the low temp units (Mitsubishi Hyper Heat).

The Mitsubishi ductless systems can be had with the variable speed technology of which you speak.

If you were wanting the same type unit I'd go with
http://www.trane.com/residential/en/products/heat ... pumps.html
Maybe a XL18i, the top of the line will be expensive not that the XL18i won't be.
It will be a lot cheaper to run then if you just replace the compressor, then something else will go bad.

Mikeeg02 wrote:If your happy with how your existing system has worked, why not just get a new compressor installed? If the coil is still in good shape, I believe you can still order just about any Freon type compressor, and the HVAC guy may not like it because it's a more miserable job but it gets you back on the road with a system you were happy with.

Mike (and everyone else who's replied) I've been tied up quite a bit during December and unable to catch up here. Will catch that up now.

My HVAC guy has been pretty straight with me over the 15-20 years I've been using him, and generally will try to fix rather than replace. He told me current laws/regulations prohibit replacing just a compressor or outside unit on a heat pump as old as mine. Old refrigerant, old tech, etc. Just took him at his word, but now I'll check it out.

69dartgt wrote:I am employed in the HVAC industry so hopefully the info I give can help you a bit. If you are happy with how the heat pump has served you over its life, I would recommend replacement of the complete system. Some of the newer variable speed equipment is very efficient at lower temperatures. Ask about variable compressor technology if you are getting a quote. I would hesitate to rely on propane at my house, just because of the availability issue that occurred last winter.

I also install MItsubishi ductless systems and they are very efficient and I wouldn't hesitate to put them in my house. If you are possibly going to rely on them for your only heating source ask about the low temp units (Mitsubishi Hyper Heat).

69Dart, about two years ago when I was first considering heat pump replacement, a rep came from one of the larger HVAC around here, and suggested a Trane variable-speed HP, with a propane furnace as backup. I plan to contact them again to get a proposal before I make a decision.

My HVAC guy in the past has suggested a ductless system for our basement, rather then upsizing the main unit and running ductwork to handle it.

LoschStoker wrote:If you were wanting the same type unit I'd go with
http://www.trane.com/residential/en/products/heat ... pumps.html
Maybe a XL18i, the top of the line will be expensive not that the XL18i won't be.
It will be a lot cheaper to run then if you just replace the compressor, then something else will go bad.

Yeah, I'm leaning toward another heat pump, debating about the backup/alternate heat source if I do that. Another HVAC contractor I got a proposal from two years ago sold several brands but recommended the Trane units.

I'm not an HVAC contractor but I've been testing HVAC units for 26 years. When it was time for me to buy one I went with Trane. My second choice would be York.