Heater(s) for trawler

[47Rah1980]

Building trawler with two cabins, 2 heads, Pilothouse, salon. Maybe 500 sq feet.

Rules are for 12-15 BTU per cubic foot

If adding heater, how many (noise?) and BTU requirements should’ve considered? Also, any comments on air versus hydronic (seems excessive) and no need for AC (n the PNW). Any know differences between Espar vs Webasto (or not significant)

Thank you.

 

[tiltrider1]

Don’t be so quick to discount AC in the pacific NW. I run mine a lot more than ever imagined. AC systems can reverse cycle and become great heat sources in winter.

 

[Doug]

We installed the Spartan model from Wallas. Very happy with it. Much quieter exhaust noise than Espar or Wabasto. Scan Marine in Seattle is the US distributor

 

[sean9c]

So probably 50-60k btu. Sure Marine shows the largest Webasto air heater at 18750 btu so you'd need a few. I'd think that with that need you're likely looking at hydronic.
Another thing to think about is with hydronic you can also heat domestic water.

 

[OldDan1943]

Remember, you need the AC power for the small space heaters. Perhaps on a 50amp boat with a ample generator, the concerns are less. I can tell you, on my American Tug, 30amp boat with an 8KW generator, I am pretty much maxed out on the amps, on the house leg, when I turn on the 2 built in resistance heaters. When it is the "cold season", I have a portable ceramic heater I can bring from the storeroom.

In my feeble opinion;
The benefits of portable heaters is, you can put the heat exactly where you need it.
The advantage of a hydronic system (of which I know nothing) is, it approaches a 'whole house' heating system.
Per an alternative for heating the domestic hot water, you should be able to have the main engine heating the water, if necessary.

 

[tiltrider1]

When it comes to diesel heaters, I am not a fan of webasto or Espar heaters. For smaller boats I like the Wallace heater, very reliable and quiet. For larger boats I like the Hurricane, very simple, reliable and easy to field repair.

 

[ksanders]

I use the Wallas forced air heaters on my 47' pilothouse cruiser based out of Seward Alaska. I have had good reliability with the Wallas furnaces. I keep my heat on all winter and last year retired a furnace with 27,000 hours on it. Seward is about 10 degrees colder on average than Seattle BTW.

On my boat I have three separate 10K BTU/hr furnaces and I think on a boat this size multiple units or zones if using hydronic are a good idea.

For example the cabins are always colder than the other levels being below the water line. The salon takes less heat, and the pilothouse less still.

As far as hydronic vs forced air, there is no clear choice except for people making the argument to support their choice. There are advantages and disadvantages to both types of heat.

The big takeaway here is that if you want to stay at 70 in your boat in any PACNW weather figure on 30K BTU as a good baseline for your size boat.

 

[Portage_Bay]

Hydronic is a bit of an electrical power hog due to fans and pumps running. A consideration if you want heat anchored out and don't want to run the gen. And when bringing the boat up from cold iron in winter can take some time. The installation is labor intensive so if you hire it done it gets expensive. On the plus uou can set the system up with zones. As noted above you can make hot water winter or summer. Additionally it's relatively simple to use waste engine heat underway. It's also simple to use the hydronic system to preheat the engine(s).

Forced air will blow warm air within seconds of startup. The better systems like Wallace are very low electrical requirements and very quiet. Forced air is simple to install compared to hydronic. But you have to find room for the ducting.

In my opinion the post #4 saying you'll need 50 ‐ 60 K BTU is over estimating what you'll need. I heat a Californian 42 LRC with a 30 K Hurricane hydronic system.

All things considered if I were to do it again I'd seriously consider the Wallace system. Mostly due to the high electrical demand of the Hurricane.

Hurricane, Wallace,, Espar and Webasto are top notch systems and you'll pay for them.. At the other extreme you can go with the Chinese knock offs of the Russian knock offs of Espar heaters. There are several threads on those heaters.

 

[Lepke]

I use a couple Chinese air heaters for mild weather and I don't want to run my main hydronic system. They put out heat quickly. When well insulated they are quiet, easy to install.

 

[DDW]

I'd vote for hydronic, for that size maybe even an Olympia or Kabola boiler. When calculating heat output for the REAL heat exchangers, use about half their specified output as a realistic figure.

Since it is a new build, have them put in the duct work for the AC, and instead of the AC put in a "whole house" style dehumidifier. You will thank me for that later.

 

[tiltrider1]

Here in lies the difficulty with these questions. Everyone has different needs so the same answer does not fit all. I have 3 different heat sources on my boat. I have reverse cycle AC, King Pic a watt resistance heaters and a Hydronic Hurricane. My needs have nothing to do with saving power. I have lots of power. My needs mostly have to do with keeping some 60' of boat warm, including defrosting my flybridge windows. While away from the Dock I have a choice of running the Genny or not. If no Genny then I run the Hurricane. If I choose to run the Genny then I can run either to the two electrical systems.

The Hurricane makes the nicest heat, is the most quiet in the bedrooms but not over all and is the most expensive per BTU. The Reverse cycles are the least expensive per BTU but they are the noisiest. The King Pic a watts are just in the middle for noise, comfort and cost.

Installation cost, the Hurricane and the Reverse cycle AC cost about the same to install with the Hurricane costing less to buy but more to install. The King Pic a watts are by far the cheapest to buy and install.

So, if I could only have one, what would I choose? I wouldn't, I'm not going to pay the price to run a Hurricane 24/7 at the dock and I'm not going to run the Genny all night on the hook. Then again, if you don't use the boat like I do you will have different needs.

 

[OldDan1943]

Lemme think..... a choice between running the generator to supply power to the heating system or freezing.....
Maybe running the main engine with the access open or freezing....
Tough call???
Come on folks, dont over think this LOL

 

[rslifkin]

If the boat spends a good bit of time at a dock (especially with non-metered power), in my mind, the best solution is 2 heating systems. Diesel fired (either air or hydronic) for when you're away from the dock, and A/C units with reverse cycle. Use the reverse cycle heat at the dock unless the water gets too cold, as it'll save the fuel burn of running diesel heat when the boat is already plugged in to shore power.

 

[firehoser75]

I have owned both air and hydronic diesel fired heating.

There are pros and cons to both. As stated: hydronic systems are easily zoned, can be used to heat the water heater or preheat the engine, as well as heating the boat. This system uses relatively thin hoses so routing them is easier than air ducts. They do take longer to heat the boat from cold, and they use a fair bit of power running multiple fans (zones) and water pumps.
Air systems starting throwing heat almost immediately and use less power. However, the ducts are much larger and routing can be an issue, but not so much in a new build. Both of my systems were Espar, and worked well for me, but they are far from quiet.
I agree with many, you should consider having multiple ways to heat your boat in the PNW, however, your main system (especially at anchor or a dock with no power) should be diesel heat. Talk to Trevor, as I am sure he has successfully outfitted many previous boats for this. I agree with DDW about installing a "full house" dehumidifier while building. Many boats suffer from high humidity especially in the winter when heating, cooking, even breathing add moisture to a warm boat that condenses on the cold windows possibly resulting in damage to your interior wood (over time).
In my opinion, A/C is not really required in the PNW, but is nice on a few days. A reverse cycle system might offer a second heat source as well as Air Con. on the few days it might be nice. However, another system requiring periodic maintenance.
Trevor should be a good source of info for you.

 

[Hippocampus]

Find the above comments interesting. Have had Espar air and Webasto hydronic. Much preferred the Webasto. Furnace was in the engine room and system was quieter than the Espar in the living spaces. The loss of storage space from ducting is a big deal. You never have enough storage space on a boat. The ducting is delicate and needs to be protected from heavy stores or those with sharp corners.
But not yet mentioned is Refleks out of Denmark. Been on boats with those and was very favorably impressed. In a new build you could put it in the largest enclosed space. They are good looking and would heat that space passively with no noise. Many of their products have a coil of tubing inside which is then run to other spaces permitting hydronic heat there. Have seen them in everything from commercial fish boats to high end sailboats. Would check them out as well.

 

[Hippocampus]

Find the above comments interesting. Have had Espar air and Webasto hydronic. Much preferred the Webasto. Furnace was in the engine room and system was quieter than the Espar in the living spaces. The loss of storage space from ducting is a big deal. You never have enough storage space on a boat. The ducting is delicate and needs to be protected from heavy stores or those with sharp corners.
But not yet mentioned is Refleks out of Denmark. Been on boats with those and was very favorably impressed. In a new build you could put it in the largest enclosed space. They are good looking and would heat that space passively with no noise. Many of their products have a coil of tubing inside which is then run to other spaces permitting hydronic heat there. Have seen them in everything from commercial fish boats to high end sailboats. Would check them out as well.

 

[AlanT]

FWIW. I am currently 6 months into a 'repower' project with our Espar hydonic heater. I wont make this any longer than it needs to be to get the message across:
My 1999 espar boiler expired. I ordered a replacement, which took two months from Germany. On arrival it turned out to be an updated model and requires substantial additional equipment (Harness, two pumps, control unit) in order to be retro compatible with the prior Espar installation. Back to Germany, four month later (today!) we finally received an email acknowledging the exact parts we would require. We are now ordering them and hopefully will be in service in another month or so.

Of course we have had no heat (except reverse AC) all winter which has severely restricted our cruising this winter.

Think through where your replacement parts are coming from before making a decision.

~A

 

[Lepke]

There are lots of ways to heat a boat w/o running a generator. The Chinese heaters run on 12v and are 5kw (about 17,000btu) each. In the PNW a diesel stove can supply heat and mine also heats the water heaters. My main heating is hydronic, but with forced air heaters instead of radiators because they heat much faster when going from a cold boat. The mains are tied into the hydronic, so cruising doesn't require more diesel for heat. And after shutdown, the residual heat in the engines are good for a few more hours of heat. And it all can run off the inverter.

 

[trawlercap]

We are toasty with the Hurricane hydroponics mated to 1952 radiators (they were recently pressure tested)
Hot fluid circulates the length of the boat in the Bilge (keeps it toasty too. And loops up into every space. From the heated Laz to the forepeak, every room and closet etc. The 58' wood beams get warmed and it feels like its radiating back...(I know, I know is a wood boat guy thing)
One image is in the lower hall, and a big one in the wheelhouse. I just started experimenting with computer fans, positioned under the radiators, they run silent, will move air through the radiators. The boat is already dry. But if my wife says "Why would you want it any warmer?" I guess I have arrived..

I give up trying to get these images vertical, I have not seen this quirk anywhere else.

 

[IRENE]

Drew,

For comparison, we have a hydronic system heated by a Webasto DBW 2010, 45,000 BTUs. It’s always been plenty of heat, but we are smaller than you.

Random thoughts, some already mentioned...

The DBW 2010 boiler has been the most problematic system on the boat. Fuel leaks, coolant leaks, sooting, poor quality fuel nozzles, etc. It is installed per the Sure Marine installation manual. Service has been difficult to non-existent to obtain. I could go on for some time about the headaches. I advise against Webasto - go with ANYTHING else.

The hydronic heat itself is pleasant - all of the lines, though insulated, do lose some heat. This warms all of the areas where the lines run (read - low in the boat) which helps to keep the entire boat very evenly heated. If left on...that is, not starting with a cold-soaked boat, the system seems to run very little.

We NEED the dehumidifier with the hydronic heat. It runs at the dock and underway. If we use the reverse cycle units, moisture is kept under control.

If I were starting from scratch, I would likely use 3 separate Wallas diesel forced air units. I think this would help with humidity control, as we would bring fresh air inside the boat to replace the combustion air. One below in the cabins, one in the salon, and one small unit in the PH ducted to the windows for a demister.

We do not heat the engine or domestic water with the hydronic loop, nor do we heat the hydronic loop with the engine. The unit was installed before our time, but I have kept it this way as it eliminates a bunch of complexity and failure points.

We supplement with an electric space heater down below when on the grid, to lessen run time and associated costs with the Webasto.

 

[Hippocampus]

Was replacing nozzles on the Webasto. We were alternating tropics and northeast US. Then found if I keep a plug or tap close the furnace exhaust when in the tropics or storing the boat I didn’t have the need to replace the nozzle. Think the nozzle deteriorates if exposed to moist salty air for a prolonged time. Think fuel leaks and coolant leaks maybe due to the installation. Think maybe you could get some unburnt fuel leaking from a bad nozzle as well. Sooting from calibration or bad nozzle. Think all hydronic systems can have all the same problems and need to be dialed in. Not just a Webasto issue. Unless we’re taking tons of green water the dorades are always at least cracked open a bit. Didn’t have moisture troubles.

 

[Nomad Willy]

We’ve been w a small Wabasto for many years and it’s a bit noisy on this forum but very nice otherwise. Engine heats our water .. makes it too hot actually. We converted to kerosene by Sure Marine’s recommendation. Buying the kero, filling the day tank, getting out (of the “hold”) and stowing it away is all busy work that we didn’t need to do before. Haven’t changed back tho.

 

[FF]

With a new boat you are in an ideal position to use simple baseboard finned tubing to deliver the heat.No wasted power with toe kick heaters in every room.

Don't forget to plumb in a towel rack in the head.

A simple circ pump will have no shaft seal, simply a magnetic drive .

Do not use 90 deg elbows in the heating circuit, the refrigeration folks have "slow els" that will speed up the circulation and use less pump power.

 

[taolsen6]

You might also check out Kabola, often found in Nordhavn and Selene.

MarineTec US | Welcome to MarineTec US in Seattle.



Talk to Costica



Have a 15 yr old unit in our Selene 53 that had been neglected and he talked me through an easy rebuild on it. Nice guy, very patient
We love the quiet heat.

 

[OldDan1943]

Do not use 90 deg elbows in the heating circuit, the refrigeration folks have "slow els" that will speed up the circulation and use less pump power.

or 2X45 deg with a bit of space between the 2.

 

[Hippocampus]

Really liked the small radiators with a fan behind them exiting at baseboard level on our hydronic wesbasto. Could aim the air flow and so quiet you needed to put a hand in front of them to see if it was working. We had a series run with multiple zones. Did find bleeding them a bit of an annoyance. That was necessary no more than once a year. Usually after the system hadn’t run for 8 months when we returned from the tropics.
The start up and running draw for AC is higher and requires the generator. With our alt. energy setup batteries were at 95-100% SOC when we went to sleep. Never ran the genset for heat. Occasionally ran the genset after breakfast to get a jump on bulk charging if it was going to be a cloudy, windless day. Did adjust thermostats to decrease usage as like a cooler boat when sleeping.

 

[Nomad Willy]

With a new boat you are in an ideal position to use simple baseboard finned tubing to deliver the heat.No wasted power with toe kick heaters in every room.

Don't forget to plumb in a towel rack in the head.

A simple circ pump will have no shaft seal, simply a magnetic drive .

Do not use 90 deg elbows in the heating circuit, the refrigeration folks have "slow els" that will speed up the circulation and use less pump power.

or 2X45 deg with a bit of space between the 2.

A little better but not nearly as good. FF has it right.

 

[DDW]

The biggest operational differences between hydronic and hot air is that hydronic can be (and should be) arranged to heat domestic hot water. Also, engine heat can be used underway for both cabin heat and domestic hot water, this heat is free.

The Webasto/Espar and ITR have very different types of burners.

While the strategy of using outside air as the intake will control humidity on a 50 deg 90% humidity day, it does little for you on a 65 deg 85% humidity day which are somewhat common in the PNW, or a 75 deg day after the cook has prepared a large pot of pasta. Nor does it dehumidify when the boat is unoccupied, unless you leave it running. A dehumidifier will do both those things as it can be run all the time. It is MUCH cheaper to have the ductwork installed at the time of build, than later. A ducted dehumidifier will work much better than a portable one, as it will circulate dehumidified air anywhere the ducts reach.

 

[tiltrider1]

The biggest operational differences between hydronic and hot air is that hydronic can be (and should be) arranged to heat domestic hot water. Also, engine heat can be used underway for both cabin heat and domestic hot water, this heat is free.

The Webasto/Espar and ITR have very different types of burners.

.

While true, running a one inch hose versus a 3 inch hose could be a make or break situation.

IRT(Hurricane) use a completely different physics than Webasto/Espar. This is what makes them so easy to field repair. The IRT can suffer from nozzle issues the Webasto/Espar suffer from coking issues. It’s much easier to screw on a nozzle than it is to decoke a burner.

 

[Portage_Bay]

OP is in Seattle. Another advantage to Hurricane for North Americans, especially for those on the PNW is Hurricane is a Vancouver BC company. Marcello at the Van BC office is great at over the phone troubleshooting. If you're in the US the Vancouver Washington office responds very quickly on parts orders.

The troubles I've had with the system were 100% due to poor installation and ignorant support from the installer. I fired them, spent less than an hour on the phone with Marcello, ordered the part from Van Wa and problems solved.

I do think the air handlers built by Real and sold by Sure Marine in Seattle are higher quality than those sold by Hurricane.