Heat Pump?

@ C · Posted: Sun Mar 19, 2006 5:31 pm Post subject: Heat Pump?

I went to look at a 2004 25 footer today. The owner says it is equipped with a heat pump. Anyone have some info on what this might be?
Maybe just to be used when on shore power? Sorry don't have anymore particulars as the cabin was locked and the boat was covered.
TIA
Bill

AstoriaDave · Posted: Sun Mar 19, 2006 9:41 pm Post subject: Re: Heat Pump?

@ C · Posted: Sun Mar 19, 2006 10:09 pm Post subject:

Thanks Dave. That was my line of thinking. I would like to have heat while out on those early and late season days. I'm not sure what they were thinking except they were in marinas with power a lot.
Thanks again,
Bill

drjohn71a · Posted: Mon Mar 20, 2006 11:23 am Post subject:

Bill, I suppose you know by now, but here goes...

A normal A/C unit uses outside air or sea water to cool the condensing coils. A heat pump can be reversed... taking heat out of the water and releasing it into the furnace A/C plenum. The colder the water, the less efficient is the heating and the more efficient is the A/C. High power consumption is due to the need for a compressor to run either direction. Safety factor is high since no flammable liquid/gas is needed, but still very inefficient heat.

Lots of trawlers use those units for heat and A/C, but you have to run the generator to run the compressor for both heat and A/C.

John

Falco · Posted: Mon Mar 20, 2006 9:49 pm Post subject:

Definitely find out what kind of amps that heat pump is drawing and then determine if the batteries will support it (conservatively). I bet it's generator driven.

@ C · Posted: Mon Mar 20, 2006 10:04 pm Post subject:

drj:
Yes, I am familiar with heat pumps and their wonderful ability to cool and expensive habits of heating.
falco:
I would not think I would want to run this at anchor offshore. but I think the previous owner did. The boat has a Honda generator. He probably used it to fire uo the ac on the less that friendly nights here in the MD region during the summer. I don't put much value on the setup. I don't like the idea pf running a generator at anchor..............
Thanks guys,
Bill

Ozark Boater · Posted: Tue Mar 21, 2006 5:47 am Post subject: Heat Pump

Bill,
There is a possibility the heat pump unit is a roof mounted model that is now available for RV's. Carrier makes a 110v heat pump/air conditioner with a 15,000 btu rating for either mode. It weighs about 90 pounds and fits a 3/4"H x 17"W x 17"L ceiling opening. The unit dimensions are 13"H x 22"W x 41"L.

Other than making an opening and supplying power to the unit, they are a simple compact unit with controls and vent ducts on the lower side. I've seen them used in a few houseboats.

If you are into gadgets, it is available with a remote control so you can operate it from anywhere on the boat.