My central AC is not getting any younger and since there are fed and state incentives of around two grand to convert my existing system to a heat pump....

Is there any reason I should not? What all is involved in this switch? My current system is all electric so there is no gas to deal with on the heater, and the existing duct work is working great. So I don't need that.

While replacing the existing outside unit is do easy even I could do it the inside existing heat and AC unit is another story. So I might as well have the whole thing done by a professional.

Anyway.... Any advice or things to watch out for?

I would defiantly do it. The current systems are very efficient. Your existing duct system can be tested for leaks. We have propane and a heat pump is less expensive.

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Tony H
W111 280SE 3.5 Coupe
Manual transmission

Past cars:
Porsche 914 2.0
'64 Jaguar XKE Roadster
'57 Oval Window VW
'71 Toyota Hilux Pickup Truck-Dad bought new
'73 Toyota Celica GT

Your existing system bite the dust? If it is then go ahead. If not I wouldn't do it. How much you think you may save per month? Divide the capital investment with the saving and you will think.twice.

It is like buying an EV while the existing car is still working great. But if you feel you are saving the world then go ahead.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

Look into th winter efficiency. I have a mini split that is a heat pump out in my sunroom. Summer is fine, winter it struggles. We have two space heaters out there to help it keep up.

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Sent from an agnostic abacus

2014 C250 21,XXX my new DD ** 2013 GLK 350 18,000 Wife's new DD**

- With out god, life is everything.
- God is an ever receding pocket of scientific ignorance that's getting smaller and smaller as time moves on..." Neil DeGrasse Tyson
- You can pray for me, I'll think for you.
- When you understand why you dismiss all the other possible gods, you will understand why I dismiss yours.

if your in cold country get the highest seer rating you can buy.other wise electric coils will bankrupt you

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1999 w140, quit voting to old, and to old to fight, a god damned veteran, deutschland deutschland uber alles uber alles in der welt

The system I have is working fine. But someday it will fail. And when that day comes I might not qualify for $2400 worth of state and federal incentives.

I can say I expect it to conk out in about five years, so why wait?

But you do have a good point.

I figured I might need a space heater or two. It drops to about -15 here at night for several weeks a year.

If you need them in Arlington then I know I will need them in central Nebraska.

But that's only for a few weeks a year.

At my age I will never see the payback on this. But my children will. I can leave the cash at my death or a greatly improved house. And this way I get to enjoy my money while I am still alive.

Air-to-air heat pumps struggle when it's below freezing, because there's little heat outside to pump into the house. When it gets really cold, heat pumps use electrical resistance heating wires to keep up with heating demand.

Water-to-air systems would work better in a cold climate, but the efficiency goes down as the heating or cooling season progresses because the ground (closed loop0, ground water (open loop) , or pond water (closed loop) gets heated or cooled. Water-to-air systems are also stupid expensive.

Heating with heat pumps is also uncomfortable. The heated air is warmer than the room temperature but less than body temperature, so if you have a vent blowing on you it feels cold.

I've got a heat pump which struggles on 0 degree days in south Ga.

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Jim

Because efficiency. Just like a low performance high fuel economy ride. You can't have both. Heat transfer is more efficient at lower temperature differentials. It is 'more reversible' -- think Entropy and the Second Law of Thermodynamics : https://www.youtube.com/watch?v=tuxbMfKO9Pg

I encourage every young person, no matter climate to invest in geothermal heat pump, where the ground is a stable temperature. They pay off in about 20 years with cheap power bills.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran, deutschland deutschland uber alles uber alles in der welt

An air-to-air heat pump is just an air conditioner that can be put into "reverse". If you can find an amenable contractor, the coil in your existing exchanger can be mated to a heat pump and your thermostat changed. And that would be it, but most likely they will want to change the whole shebang.

As for leaving this as a legacy, how long did your A/C compressor last? The useful life is probably ten years, give or take. There's no reasonable expectation that a heat pump will last any longer.

When buying a heat pump, the contractor will generally give you as specification for "COP", not a "SEER". The green energy field is filled with misleading data, COP is a great example. COP is the "efficiency" of the system relative to the energy consumed. A COP of 4 would mean that it extracts four times more heat from the air than it consumes in power. BUT, and this is important, COP is often misleadingly quoted at "standard conditions," or 70F. It will decline as temperature goes down, meaning that it's not a single number, but rather a curve. Somewhere around zero, the heat pump will have a COP of 1, meaning that it extracts as much energy from the air as the electricity consumed. So when you are told that a heat pump can work "all the way down to ten below", it's true enough, but the COP will be so low that it would be cheaper to heat with a resistance coil.

For my own use in the cold Northeast, I considered and rejected conventional heat pumps, regardless of subsidies. I would still be reliant on supplemental heat for half the winter, so it's not at all clear that there would be any benefit except in the "shoulder months", when it's not that cold. The subsidies mostly go to the profits of the manufacturers and installers, no benefit to the homeowner after the hired help takes their cut.

I would install water-to-air geothermal, which is a different kettle of fish, but only if I was doing new construction. The cost of retrofitting a well field or loop is cost prohibitive, and very disruptive. I have to live here while they'd be tearing up my yard.

My advice in considering green energy projects is "mind the bullsh_t." As usual, we're going to get to the future and find that it's not what they promised.

I am so glad I asked this question. Nothing is better than first hand information from someone who knows what they are talking about and is not trying to sell me something.

However old this thread gets I hope anyone with information the others could find useful will keep posing it.

Air-to-air systems are now just as efficient, 20+ SEER.

Ther's no such thing as sable ground temperature. My neighbor has a water-to-air. It works great in the spring and early summer, and sucks hind tit in July and August because the ground has been heated.