Heating Ideas

[Pelagic]

My Filipino partner really wants to cruise to Japan and go salmon fishing in Alaska and British Columbia, where we have family living in the Gulf Islands. (So we might winter there)

All very doable with Stargazer, but, as a steel boat with uninsulated hull, that is the challenge!

My first thoughts would be to replace the very large AirCon compressor and ducted air handler in the Engine Room with a ducted heating system (preferably Diesel fueled)

That AirCon is tremendous overkill (I have 3 other small units), so will not be missed in the Tropics

I am thinking something like a diesel furnace in my engine room, with hot air spliced into the existing air con ducts for heat distribution.

I would have a large empty footprint in the ER if I remove that big AirCon, which we never use, but no experience with modern marine heating systems for the PNW, or other concerns.

Unfortunately, no room in accommodation for a diesel stove.

Is there a reliable marine rated diesel furnace that you could recommend for my research or any other ideas and thoughts?.

Life was so much more simple before she fell in love with Sushi! [emoji4]

[Paul L]

Check ITR Hurricane Zephyer, nice because it also offers on-demand hot water, so it is useful when you are not in cold climates.
Refleks also has some reliable heating solutions

[Pelagic]

Thanks Paul

[Dymaxion]

Check out both Webasto and Eberspacher. Both make compact diesel (and gasoline) burning furnaces providing hot water or hot air based heat. 12 or 24 volt. Good place to get a used system is from heavy/highway truck salvage yards. Used for cabin heat and engine warming and available in a wide range of capacity.

You are going to lose a huge amount of heat unless you get some insulation installed. You will also get lots of condensation on the hull, draining to bilge hopefully. May want to search on CF for ideas, been discussed well.

[john61ct]

I would go Espar/Webasto diesel, but hydronics, not air blower units.

Pipe hot "water" to strategically located exchangers (radiators) either passive down low and / or quiet little fans to circulate the heated air.

Get HWS at the same time, calorifier.

Take advantage of engine heat while underway, also maybe engine preheating function, easy to include.

If spending long periods in cold places, look hard at insulating at least some living area, beds not so critical but dining / galley / shower.

Some people DIY but best IMO to get a pro to at least consult remotely, help source the components.

[Lepke]

A bad feature of a furnace in the engine room and ducting is an engine room fire goes right up the ducts. And you can't starve a fire because air can be drawn in thru ducts.
I have an 83' boat in the PNW and live aboard. I have a diesel fired hot water boiler and individual heater/blower units in cabins. Originally the boat came with baseboard radiators. The air units warm a cold boat quicker than the radiators. And no thru the deck ducts.
I been in below zero weather and maintain comfort levels. Insulation makes a big difference in comfort and in heating costs. I also have a diesel stove, wood stove and pellet stove.

[wrwakefield]

Pelagic,

Since you already have ducting installed and distributed, hot air heating is an excellent approach for the latitudes you are considering. [I have had just about every type of heat on 5 different boats over the years between 55 and 62°N.]

You will very likely need to insulate the ducting- and at least the living areas of the boat. The duct will need insulation to reduce heat loss in your distribution system [and will help with A/C efficiency in the future...] Living areas will need insulation to reduce condensation and decrease heating [and cooling] loads.

Hot air is nice because you are also distributing fresh air if the heater make-up air [not to be confused with combustion air...] is appropriately set-up. This is something we do not get with hydronic heating. [e.g., In the cold climates, we install Heat Recovery Ventilation systems in our homes to refresh/exchange the air we live in. I have been looking for a compact version for the boat without success...]

In addition to the diesel fired hot air furnace, you might also consider a hot water heat exchanger on the engine coolant loop [i.e., hot water to hot air distribution] that shares the same duct work as your impending diesel furnace [since, like us, you will likely be motoring more than sailing in the areas you mention...] This is not to be confused with installing stand-alone 'bus' heaters... The heat exchanger I'm suggesting [i.e., hydronic air handler] would also be installed in the engine room sharing the hot air duct with the diesel furnace[s] you install.

Regarding marine grade diesel fueled hot air furnaces, Espar, Wobasto, and the ~50% cheaper Russian Planar all have capable models for your needs. [I have experience with all 3, Wobasto being in the distant past.]

They will all do the job, and installing in the engine room is a safe approach. [We have an automatic fire suppression system in ours, therefore I feel better with the primary heating devices residing there as well.] Just be sure to duct for make-up air from outside the engine room. Combustion air isn't usually an issue as the engine rooms are well ventilated already.

I would recommend springing for the use specific mufflers [silencers] for both combustion intake and exhaust. It greatly quiets the jet engine effect both inside and outside the boat for the larger unit[s] you will likely require for your vessel. [e.g., Espar D8LC and equavilent. Some people install 2 of the next size down (e.g., Espar D5L) so you can run only one in cool weather, and two when it is cold- and have live back-up as well.]

I could go on and on- and am happy to- but wanted to let you know you are on the right track.

If you desire more background and details, I have written a series of posts on our [ad free] blog around the topic of living on a boat in cold weather. Some even link back to discussions on this forum.

In case any of this is useful, and best wishes deciding what is best for your needs...

Cheers! Bill

[Pelagic]

Thanks to All for the input.
It is encouraging that Bill, with his location and experience thinks Im on the right track, so here is more info and visuals to fine tune my understanding.

Existing Insulation:
The boat was built in Holland for a German Owner, so already has 2" Rockwool insulation (Foil 2 sides) between the steel deck and Headliner
Same on cabin sides and Hull down to waterline.
I have access to bilges to insulate below the waterline if it was advised, but I thought if I ran my ducts low in bilge, the radiant heat and open circulation would be a better solution for the cold sea water temp.. insulated or not...I just dont know on this??

First two sketches show location and ergonomics of ER Port and Starbaord and the next 2 pictures show the AC equipment, I would remove.

The 220v insulated Hot water Heater works well in tropics, but if I can valve and T-off the cold water supply and bring in Hot water from Furnace instead, that would be more cost effective. My uninsulated copper pipes would obviously be inefficient, but I can live with using that radiant heat in Bilges.

Last 2 pictures show the Port Pilothouse side during refit and the side deck risers which provide fresh air ventalation and room for combustion exhaust.

Need to study temperatures and safety for the furnace exhaust...how hot does it get?

For hot air ducting, I am thinking small insulated piping for long runs to move the air fast and then spilced into the larger but short Air Con Ducts and vents as expansion areas to slow and quiet down the hot air.

Note on last Photo the return vent on side.... All my small AC fancoil units have a fan only and return vent, so Bill, is that what you meant by a recovery system?

[wrwakefield]

Hi Pelagic,

I'll embed some responses within your email, below, for clarity. [In Blue]

One point of confusion for me is in some of your statements you are talking about hot [forced] air heat, and in others hot water [radiant, or hydronic] heating. I will respond to each accordingly, but it might get confusing quickly as those two approaches have unique design considerations...

My original response was with regard to hot air heat only as I thought that was what you were considering... [more to follow...]

Originally Posted by Pelagic

Thanks to All for the input.
It is encouraging that Bill, with his location and experience thinks Im on the right track, so here is more info and visuals to fine tune my understanding.

Existing Insulation:
The boat was built in Holland for a German Owner, so already has 2" Rockwool insulation (Foil 2 sides) between the steel deck and Headliner
Same on cabin sides and Hull down to waterline.

Perfect. That should be more than adequate. Any uninsulated areas [or improperly insulated areas...] will reveal themselves once you live aboard during cold weather.

I have access to bilges to insulate below the waterline if it was advised, but I thought if I ran my ducts low in bilge, the radiant heat and open circulation would be a better solution for the cold sea water temp.. insulated or not...I just dont know on this??

I wouldn't insulate the bilges either. Too much fuss and often you can insulate under the soles in areas of concern.

Or if you decide to go with hot water heat, heat the soles in living areas [and under berths, sitting areas, shower pans, etc.]... very posh...

If you are talking about running hot air ducts through the cold bilge, just use well insulated ducts [moisture resistant insulation- I recommend against fiberglass... there is closed cell foam for HVAC duct use...] or you risk loosing too much heat in the longer runs... [From personal experience...]


First two sketches show location and ergonomics of ER Port and Starbaord and the next 2 pictures show the AC equipment, I would remove.

The 220v insulated Hot water Heater works well in tropics, but if I can valve and T-off the cold water supply and bring in Hot water from Furnace instead, that would be more cost effective. My uninsulated copper pipes would obviously be inefficient, but I can live with using that radiant heat in Bilges.

If you choose to use or include a hot water [hydronic] heat source in addition to or leu of hot air heat, you might as well also make hot water in your existing water heater. [Likewise, consider heat exchangers on the main engine[s] to supply heat to radiant loop when motoring, and to preheat engine[s] if you ever venture to even colder climes...

Last 2 pictures show the Port Pilothouse side during refit and the side deck risers which provide fresh air ventalation and room for combustion exhaust.

Need to study temperatures and safety for the furnace exhaust...how hot does it get?


They get hot. [Sorry, mine is disconnected for maintenance or I would take some measurements...] Therefore Espar [lets use Espar Airtronic heaters as an example] requires insulated double-wall stainless exhaust tubing for marine installations. They also suggest a 2 meter max length for the exhaust run using their stock the 24mm ID stainless steel 'hose'. They also offer 30mm ID tubing for longer exhaust runs [like my 4 meter run...] You could also put together some solid exhaust pipe runs [and insulate them] if that helps.

As an aside, a method used by some manufacturers [e.g., Wallas, Dickenson propane heaters, etc.] to keep the ehhaust run cooler- and to preheat combustion air- is to draw combustion air through an outer tube surrounding the exhaust tubing. [Wallas has fittings to accomodate this with a single hull penetration.] I have installed this way on a past vessel and it is very effective, but not required...


For hot air ducting, I am thinking small insulated piping for long runs to move the air fast and then spilced into the larger but short Air Con Ducts and vents as expansion areas to slow and quiet down the hot air.

That would probably work. However, I would go through the duct design process following the guidlines for the specific heater you choose and compare those results to your idea. e.g., Espar has a detailed approach that is not unlike that for designing NMEA2000 networks. [e.g., They use integer values for components, the sum of which should not be exceeded by the completed system.]

Regarding sound of air in ducts- my experience has been that the sound of the air is minimal compared to the sound of the heater being transmitted through the duct work... Hence my recommendation for the heated air inlet and outlet mufflers [as well as exhaust muffler...]

Note on last Photo the return vent on side.... All my small AC fancoil units have a fan only and return vent, so Bill, is that what you meant by a recovery system?

On air handling systems, they refer to it as make-up air. Like a water pump circulating water through a closed plumbing system [e.g., radiant heat], air handlers do the same; they recirculate the air [and that is all you get with most hydronic systems... recycled air compounding the moisture concentration since no new air is introduced...] I is highly desirable- and no issue in the latitues you are discussing- to introduce a percentage of fresh [outdoor air] at the inlet side of the hot air fan.

As an example, our forced air system is in the engine room- which is well ventilated for the engine, and heater combustion air is drawn in through the engine room vents. The heated air inlet side of the heater is ducted outside the engine room to an adjoining cabin [our workroom/toolroom/laundry room.] There the air is drawn from the rest of the boat [under the door to that cabin- which is ~2" above the sole when closed...] for recirculation. We leave a port open in that cabin year around, so a reasonable percentage of fresh, outside air is drawn in to the air being heated when the heater is running- thereby distributing it throughout the boat.

A planned future modification for fresh air is to put a Y valve on the duct for controling proportions of inside vs. outside air so we can tune the system in extreme cold. [i.e., less cold, fresh air when below zero F or the heater starts loosing efficiency...]

Note that this same make-up air approach could be used with the individual air handlers that would make up a hydronic heating sustem. The fresh air ducting to each handler would just be a bit more complicated... This is where an HRV [Heat recovery ventilator] might be a better approach.

Let me close this series of feedback with some quick thoughts regarding what might I spec if I were in your situation. [I call this the 2 minute drill- an arficial time limit for making a decision based on what I think I understand and think I already know- as a consumer...]

First decision: Forced air [and] or hydronic?

1) Forced air would likely be a cheaper and faster install based upon your feedback so far. [I'll stay consistent using Espar as examples since that is what I am most recently familiar with... You can cross reference to other manufacturers for comparison...]

An Espar D8LC would likely be more than adequate for your boat. [But a single D5L would likely not be sufficient... I have had both on different boats.] This is likely your most cost effective solution for the latitudes you have mentioned.

Two D5L heaters would also work well- providing finer control during fringe seasons [only run one heater when it isn't that cold...] and providing redundancy. This complicates installation and maintenance, and increases cost. [This may cost about the same as the hydronic solution, below.]

2) Hydronic adds the ability to heat the entire vessel [including radiant in floors, seats, berths, etc.] provide domestic hot water and tie to main engine[s] for heat exchange both ways [heat boat, etc., while motoring, and preheat engine[s] /generator[s], etc. in cold conditions.

It also complicates the installation [multiple air/heat exchangers] and the fresh make-up air needs previously mentioned.

Hydronic is an optimal approach [and likely most expensive in your case].

I plan to add it as my primary heating in the near future using the appropriate Hurricane 'boiler' model. I'll use the hot air heater in ventilation mode [i.e., no heat] to distribute fresh air through the existing heat ducting.

My goal here was to contribute some clarity and ideas for your consideration. Let me know if this all makes sense... What you are doing is similar to what I have been planning before we embark for higher latitudes in the next year or so...

Best wishes sorting out what is best for your plans...

Cheers! Bill

PS: Our vessels are similar in cross-section. All the systems I mentioned fit very well in our available spaces [which are proportionally smaller than yours...]

[Cheechako]

I like the Webasto's. They seem reliable and good. On a boat your size you may consider 2 small ones rather than one big one and tons of ducting. If you want to never have an issue install a kerosene tank and run them on kerosene. It's available in 5 gallon cans and burns super clean. Those units dont use much fuel at all.

[john61ct]

Best to just plumb into the propulsion fuel for simplicity. Locate the feed line so heating on the hook can't leave you stranded.

Webasto and Espar are both excellent build quality.

Planar below, but great if half the cost.

Chinese knockoffs are an unknown quantity but cheap enough you can buy your spares in advance.

[john61ct]

Originally Posted by wrwakefield

the use of

[square brackets] rather than (parens) screws up the display of your message

In particular a single s in brackets, interpreted by many browsers as "strikeout" font style

[wrwakefield]

Originally Posted by john61ct

[square brackets] rather than (parens) screws up the display of your message

In particular a single s in brackets, interpreted by many browsers as "strikeout" font style

Thank you for letting me know John. Having any character interperted as something else would be annoying

Would you share which browser(s) you have seen exhibit this behavior?

I have not experienced this in the 4 browsers and 2 email clients I routinely use, so am therefore curious which one(s) are not up to HTML5 standards...

I also wonder how many others users are having similar experiences? (You are the 1st to ever mention it, and being lazy I have always used square brackets as is saves me the arduous task of using the shift key... ;-)

Thank you.

Cordially, Bill