Heating Systems

[Dockhead]

How I remember the days when air conditioning was the main HVAC issue on boats for me -- in Florida.

Now my home port is above 50N and my favorite cruising grounds are even above 60N -- the Arctic Circle itself is 66.56.

So now obviously heat is the main issue, not aircon. I use heat year around, and I have a lot of space to heat. My boat was built with an Eberspaecher 10kW central furnace which circulates an ethylene glycol mixture around the boat to run three fan coils, plus domestic hot water heating. The Eberspaecher is not user-serviceable (big minus) and requires a bit of attention on a regular basis, but in general I can't complain too much about it -- after the last service almost two years ago it has been running perfectly, starting on the first attempt, etc. It does make some noise and does consume some precious diesel fuel -- unpleasant when you're paying full taxes on it -- and for that reason, I rarely leave it running all night. I tend to warm the boat up with it in the evening and shut it down when I go to bed, unless the temp outside is near or below freezing. Then run it for a couple of hours in the morning.

In the Baltic, berthing is incredibly cheap (as cheap as 13 euros for a 54' boat), and the marinas ("guest harbors") are mostly in beautiful and interesting places, and outside Germany, the electrical service seems to be all 16 amps. So here I have been spending much more time in ports and less time at anchor than I usually do. With the good electrical service, I heat with electric fan heaters most of the time. Two kW of heat (two heaters running on "low") have been keeping the boat nice and toasty (and dry) even in temps of 5 or 6 degrees.

The cheap Chinese fan heaters are a real KISS solution, but I find myself thinking about something more elegant.

For example, about heat pumps. I have no aircon on my boat and don't need it anywhere I have cruised the last five years, but at times like this (air temp 10 degrees; water temp 16 degrees) a heat pump would be fantastically efficient.

Has anyone ever spliced a heat pump into a central heating system on a boat? I have trawled the CruiseAir site and see that they do sell central water chillers/heat pumps, but there is no information about whether they can be used in an existing central heating system.

It seems to me that electrical resistance heat could also be added to the existing central heating system, and this should be quite simple, compact, and cheap. But I have been unable to locate suitable equipment.

Lastly, I still dream about getting engine and genset waste heat into my central heating system (there was a thread about this last year, where I got a lot of useful advice, but still couldn't come up with a satisfying conclusion).

Anybody have any practical ideas? Experience to share?

[richnjohn]

I have a system like yours but mine is Webasto. I have heat exchangers on the engines tied into the hydronic heating and domestic hot water heater loop to use the waste heat. I can also use the diesl boiler to pre-heat the engines.

Sure Marine has an online catalog with all kinds of heating parts. They are also really good to work with. I installed the system myself and had to call them a few times for advice, always helpful.

www.suremarine.com

I 've often wondered the same thing about splicing water chillers into the system but have never seen it done.


Sent from my iPad using Cruisers Sailing Forum

[rw58ph]

We have a Webasto diesel boiler also that heats the entire boat including the engine room and keeps most of the bilge dry. Webasto is built in Europe so there is probable a dealer close to you.

[ranger58sb]

Heat pump, sorta. Review http://www.cruisersforum.com/forums/...on-122662.html post #38.

I've seen other threads about split home systems, like some Mitsubishi units...

-Chris

[Dockhead]

Originally Posted by richnjohn

I have a system like yours but mine is Webasto. I have heat exchangers on the engines tied into the hydronic heating and domestic hot water heater loop to use the waste heat. I can also use the diesl boiler to pre-heat the engines.

Sure Marine has an online catalog with all kinds of heating parts. They are also really good to work with. I installed the system myself and had to call them a few times for advice, always helpful.

Sure Marine

I 've often wondered the same thing about splicing water chillers into the system but have never seen it done.


Sent from my iPad using Cruisers Sailing Forum

Thanks; very useful. I'll have a trawl through that catalogue.

You've already implemented part of what I am thinking about. Can you explain in more detail how the heat exchangers work with the Webasto? Did you put in a separate pump and do you pump glycol through the Webasto when it's not working (that is, when you are getting heat from your engines)? Or do you bypass the webasto? Or do you use the Webasto's built in pump, wired up how?

This would all be very helpful to me. I figured it must be common practice on power boats.