Advice on DIY Heat Pump?

wildcat33

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Just moved into a 120 year old house with a 25+yr gas forced air heating system and no AC. Heating unit will need to be replaced soon. Local contractor quoted me 15k for a mid level combo gas heat and A/C unit and that just ain't going to work for me, this property is basically a live in flip, so just need the basics of comfort and reliability. I was thinking of installing a Mr Cool Universal unit on my own. Colorado climate seems suitable for the range in which they work and they look pretty easy to install. Plus the damn things ship free on Amazon to your doorstep. Install looks like: pour a small slab for the condenser, patch in the new air handler where the old heater was, run the condenser lines, and wire it up. Electrical is my weak spot, but it still doesnt look tough. I have 240v nearby and a new panel, so could add a 35amp breaker if needed. Ductwork to patch it in to the existing layout might be a pain if the dimensions are different, which i expect they are.

Anyone have any experience with these things? Pro's / Con's?
 

Stalker69

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I do hvac, I personally would not go with a heat pump, especially by it self with an air handler. We don't do many of them, but the ones we do have gas furnace back up ( emergency heat ) Electricity in many cases cost more to run then nat. gas. Plus the colder it gets the longer a heat pump has to run to satisfy the the call for heat. In southern climates or when natural gas is not an option, heats pumps are a good option. I would also think a heat pump with air handler would cost more then the furnace, a/c units.
 
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Newer inverter compressor technology has brought the heat pumps into being sufficient stand alone heating and cooling systems. I personally would do a duel fuel system with gas backup if you wanted the heat pump capability. In your scenario, a basic direct vent furnace with a split ac system would be the perfect price point. As far as DIY you will run into hurdles of EPA certification with the ac equipment.
 
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wildcat33

wildcat33

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Newer inverter compressor technology has brought the heat pumps into being sufficient stand alone heating and cooling systems. I personally would do a duel fuel system with gas backup if you wanted the heat pump capability. In your scenario, a basic direct vent furnace with a split ac system would be the perfect price point. As far as DIY you will run into hurdles of EPA certification with the ac equipment.


What do you mean by epa certification? I dont plan to pull any permits for this, but will look for rebates on the heat pump.

A side benefit of getting rid of gas is that I can remove the gas furnace exhaust vent, which has a funky route, foundation penetration, and connection to the outside of the house.
 

bozeman

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DIY heat pump..........don't. I mean this in all respect, but if you have to ask about EPA certification and potential issues.....I would pay the 15k.
 
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EPA certification is required to purchase professional refrigeration equipment containing freon. Mr Cool has some loop hole where the lineset is pre charged and the system is "sealed" so you don't have a potential to leak freon into the atmosphere. Still not sure how they are able to sell this to the general public as there is still quite the potential for a leak.
 
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Newer inverter compressor technology has brought the heat pumps into being sufficient stand alone heating and cooling systems. I personally would do a duel fuel system with gas backup if you wanted the heat pump capability. In your scenario, a basic direct vent furnace with a split ac system would be the perfect price point. As far as DIY you will run into hurdles of EPA certification with the ac equipment.

I have a hybrid system. The system uses heat pump till the temp drops below 40. Then it switches to heating oil. However I rarely use the heating oil or heat pump because we have a wood stove.
 

GSPHUNTER

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I worked in the trade for 40+ years. I was never a fan of heat pumps. In colder climates they are not as efficient as say a gas furnace, or even electric heat. You did not mention the size of your house. The Mr cool units on Amazon only went up to 30,000 btus, which at best is good for 1200 Sq. Ft. house. I notice one other thing. The unit came with 16 ft. line set, which are precharged with refrigerant, so unless you can place the units no further apart than that, you will have to run additional copper lines, which will require additional work soldering lines and then running a vacuum pump on system, and then adding additional refrigerant to allow for longer line set run depending on how much longer copper lines are. Also if much further than 16 ft. you may need to use larger size copper, maybe one size larger. Just something to consider.
 
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Weldor

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We run a 5 ton heat pump down here in sourthern az. highs in the 100's and low's in a good winter 20's works fine. If you need back up you can put Aux. heats strips in. We've never needed to use them. we get snow and freezing temps regularly. We just had our unit replaced in January, the old on was a 2002. With the crane fee (it's on the roof) $8200 for the pack unit installed. If I would of had it done last year it would have been half that. New epa crap. The old one waited until January to quit. My Luck.
 
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wildcat33

wildcat33

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We run a 5 ton heat pump down here in sourthern az. highs in the 100's and low's in a good winter 20's works fine. If you need back up you can put Aux. heats strips in. We've never needed to use them. we get snow and freezing temps regularly. We just had our unit replaced in January, the old on was a 2002. With the crane fee (it's on the roof) $8200 for the pack unit installed. If I would of had it done last year it would have been half that. New epa crap. The old one waited until January to quit. My Luck.

What size house are you conditioning with a 5 ton unit?
 

bobr1

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Just moved into a 120 year old house with a 25+yr gas forced air heating system and no AC. Heating unit will need to be replaced soon. Local contractor quoted me 15k for a mid level combo gas heat and A/C unit and that just ain't going to work for me, this property is basically a live in flip, so just need the basics of comfort and reliability. I was thinking of installing a Mr Cool Universal unit on my own. Colorado climate seems suitable for the range in which they work and they look pretty easy to install. Plus the damn things ship free on Amazon to your doorstep. Install looks like: pour a small slab for the condenser, patch in the new air handler where the old heater was, run the condenser lines, and wire it up. Electrical is my weak spot, but it still doesnt look tough. I have 240v nearby and a new panel, so could add a 35amp breaker if needed. Ductwork to patch it in to the existing layout might be a pain if the dimensions are different, which i expect they are.

Anyone have any experience with these things? Pro's / Con's?
Obviously central is better for whole house and convenience, but cost can be considerable. I looked at doing Mr. cool. But at the time they were not quite as good as Mitsubishi. Bought house with just fireplaces and baseboard. I’m in Montana and there was a huge rebate for using minisplits. It was almost the same price to have someone do it vs me doing it myself. I also got a 12 year warranty. Electrical company wouldn’t reimburse for a diy so i had a company do the mitbushi hyper heat. It’s the prime heating unit/ and AC for the entire house and has worked great. Though when we do have some seriously cold days the baseboards are needed to augment, as the unit is rated down to -15. And we had several days/weeks this year that were cold….
 

Stalker69

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We run a 5 ton heat pump down here in sourthern az. highs in the 100's and low's in a good winter 20's works fine. If you need back up you can put Aux. heats strips in. We've never needed to use them. we get snow and freezing temps regularly. We just had our unit replaced in January, the old on was a 2002. With the crane fee (it's on the roof) $8200 for the pack unit installed. If I would of had it done last year it would have been half that. New epa crap. The old one waited until January to quit. My Luck.
 

Stalker69

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You probably don't have natural gas avaliable, I know my sister and many friends that live in Arizona don't. Here electric heat strips would cost a ton, and as cold as it gets here, you need a back up heat source to a heat pump. Or it will run pretty much continuously alot of days and nights sometimes.
 
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Just moved into a 120 year old house with a 25+yr gas forced air heating system and no AC. Heating unit will need to be replaced soon. Local contractor quoted me 15k for a mid level combo gas heat and A/C unit and that just ain't going to work for me, this property is basically a live in flip, so just need the basics of comfort and reliability. I was thinking of installing a Mr Cool Universal unit on my own. Colorado climate seems suitable for the range in which they work and they look pretty easy to install. Plus the damn things ship free on Amazon to your doorstep. Install looks like: pour a small slab for the condenser, patch in the new air handler where the old heater was, run the condenser lines, and wire it up. Electrical is my weak spot, but it still doesnt look tough. I have 240v nearby and a new panel, so could add a 35amp breaker if needed. Ductwork to patch it in to the existing layout might be a pain if the dimensions are different, which i expect they are.

Anyone have any experience with these things? Pro's / Con's?
Hire it out. Don’t be that guy.
 

SwiftShot

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My buddy put one unit in his house. He has a very open concept and only 1800 square feet. It worked great, he does have a fireplace as a backup but never has used it. While a gas furnace is usually cheaper, not everywhere has gas lines. If you must have propane then, well that gets expensive. Heat pumps have a goldie locks zone. It was 25 to 95, those where were they worked best. Newer systems are moving those number in both directions. The US and Canada have challenged companies to make heatpumps that work into the negatives. There are 3 companies that have them that work down to minus 10.

Back to your MR Cool. I would call Signature Solar. They sell kits for off grid people to install themselves. Have your square footage and insulation rating and they will match you up with the right system.
 

Weldor

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No gas up here. our bills run about $260 to 300 depending on the temps. Only bill we have . No gas ,water etc. Like I said we have never used the strips. One note is these new systems go into defrost mode alot. Not a big deal just drops the heat out for a few minutes.
 

Fowl Play

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Not in HVAC but have used the Mr Cool pre charged units several times at work. Surprised how easy set up is and how long they last, even in a semi-marine environment we subject them to.
 
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wildcat33

wildcat33

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I’m pretty convinced that the newest heat pumps can handle our temp range (0-100 let’s say). I’m still doing the research to decide. Everyone’s input is helpful.

I’m flat out not paying someone 10k to install a 5k appliance that only requires minor electrical (and possibly gas) to install. So any other DIY suggestions are welcome.
 

GSPHUNTER

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In most cases a fuse disconnect is not required if condensing uint is within eye site of breaker panel, same wall. there could be a max. distance allowed. 30 amp=#10 wire, 40amp=#8 wire. Ground wire, green should be same size of load carrying wire. As I mentioned prior, If the condensing unit is located further away from fan coil unit than supplied line size provided, which if I remember is 16ft. you will need to run new line set, unless you can check with manufacturer and request longer line set. These are precharged lines so it won't require running vacuum pump. Some units come with what is called a holding charge, not full charge, which will require adding/topping of refrigerant charge.. Condensing unit should have pounds and ounces of what charge is listed on name plate.
 
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