Thread: Heat Pumps
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Old 10-18-2020, 07:23 AM   #30
FF
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The drip heaters like the Dickinson work well, there limited to about 20,000 btu and with a gravity fuel system need zero electric , so a winter on the hook becomes reasonable.

I lived aboard for a couple of decades in the NYC area and was a dealer for Dickinson and Espar.

Many folks found that the 16-20,000btu worked fine but a few needed 2 heaters , a range and a second unit for the really cold -0F weeks .

My personal choice was a floor mounted unit with 3/4 finned tubing and only thermosyphon to move the water. As the total head was small , perhaps 7ft I was not sure it would work.

Hooked up for the first winter I used rubber heater hose and was delighted , it worked.

The second summer I replaced the rubber hose with copper tubing and fittings , & the circulation stopped working .A few reference books (Algore had not invented the internet yet) and I learned of the high resistance of 90deg elbows.

The refrigeration folks have "slow" elbows and 45deg fittings so I replaced the plumbing items with fridge stuff. It then worked.

I found that a constant temp of 135F of the circ water was perfect for indoor T shirt comfort. I was the thermostat .

The unit , once fitted with the proper H smoke head was reliable enough to go to work 2 to 4 days , depending on weather.

The extra heat required if a quick start was needed came from a Shipmate wall fireplace,loaded with charcoal it would heat all night.

Other companies make drip pot heaters that are larger.


I had tried the Espar on a previous boat , a 45 ft cold molded Tri and found that due to the light construction and lack of insulation (to avoid condensation in the wood surfaces) the operating noise was hard to live with.

The unit sounded like a Hoover in the next cabin.

On a really big boat I would install baseboard heating tubing and a Peerless or other premium house oil furnace , an inverter and a big pile of batts, for when the dock is down.


https://www.peerlessboilers.com/products/series-wbv/
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