Heating aboard in the Pacific NW

[Jack Tyler]

I'll admit my motivation for starting this thread is a selfish one, as my wife & I are considering cruising for an extended period in the Puget Sound to Desolation Sound area while living aboard. But surely there are other NW cruisers - current and future - who are also curious about the experiences other live-aboard boaters have had when heating their boats.

I'd like to pose 2 specific questions but please allow this thread to go where y'll need it to.
1. What have others' experiences been with a bulkhead-mounted diesel or kerosene-fired heater on smaller boats, e.g. a Dickinson, Force 10 or similar unit? While we've had previous experience with a forced air Espar unit, where cabin-by-cabin heat ducting was the norm, we haven't had much experience with these single-source heaters. How essential is it for a small fan to redistribute the warm air? Given the mid-height location on the bulkhead, how does such a unit keep one's tootsies warm? (Beyond wearing socks, I mean. <g>) How helpful is a main cabin-mounted heater to those sleeping up in the forepeake? I'm fishing for lots of personal comment here, so don't think weekend or one-week vacation experiences don't count. (In the land of the blind, the one-eyed man is King...).
2. Condensation. Surely, many who are reading this know why I'm asking about it. When we lived aboard in Maryland, where single digit low's and occasional snow were not uncommon during winter, we found this to present a big battle for us - even with a forced air system (no combustion occurring inside the boat) and a well-insulated deck & cabin top. Any clever products and/or techniques would be great to hear about. And perhaps I'm more worried about this than the temps in the Pacific NW warrants - you'll have to tell us!

Thanks for whatever comment you can provide. We're all ears (well, eyes...).

Jack
Currently with tongues hanging out in St. Pete, FL's summer weather

[strongsail]

Jack,

Thanks for posting to NWBN, and self-interest is a great excuse to be here! You ask the questions, and we all get benefit from the answers! What's selfish about that?

As a former installer and marine service business owner in Seattle, I have seen lots of heater installations - good and bad - and have (as you might imagine) lots of opinions on the subject.

First, a safety statement:

1. When looking for a heater, Forget Propane. Some insurance companies (including the one I work for) will not insure boats with propane-fired devices (space heaters, water heaters, refrigerators) that can "start unattended" - i.e., with a pilot light or piezo-electric starter.

2. When planning and budgeting a heater installation, include a Carbon Monoxide (CO) detector in the plans. All combustion produces CO in varying amounts. Be sure the detector is designed for marine use. On a larger boat with multiple sleeping spaces, you may need more than one detector.

3. Be sure your installer is qualified, has factory training, and understands and follows ABYC standards. If it's a DIY project, read and follow the instructions from the manufacturer and/or distributor to the letter, and drive the dealer crazy with questions if you're not absolutely clear on how to do it. I have seen completed installations simply not work - the heater's fail-safe devices shut it down, and the only solution is to Rip Everything Out and Start Over. Not fun.

Okay, on to your questioins:

Self-contained space heaters produce nice "hot spots" like a fireplace at home, which can be pretty inviting - a nice place to warm your cold hands after a sail change in the rain. They are less expensive, simpler to install, and are usually seen on smaller boats. The exception to that is the diesel cookstove often seen on fishboats and some pleasure boats, which heat the coffee and the boat at the same time. But making coffee in the summertime will drive everybody out on deck pretty quickly. The bulkhead-mounted units are usually mounted as low as possible to prevent the "cold tootsies" problem you mention. and many installations include a fan of some type, either in or near the heater, usually as a factory-provided option, or an aftermarket fan mounted near the ceiling to improve circulation. But, many folks want this type of heater because it doesn't use battery power, so the circ fan kind of defeats the purpose - again, especially true on smaller boats where power consumption is an issue. Wherever the bulkhead heater is mounted, it will have exposed flue pipe in the cabin, which is a burn risk and needs to be protected so people won't inadvertently use the flue pipe as a handhold when the boat is in a seaway.

"Central heating" systems, including those from Espar, Webasto and Ardic, generate either hot air or hot water to heat the interior of the vessel. Hot air installations take up more space with ductwork, but they are more efficient in terms of electrical consumption because the whole system runs on one motor, which provides combustion air and moves room air, and a little bitty pulse pump provides fuel. Hot water is physically easier to install, and takes up less space, with heater hose instead of ducting, but it's technically more difficult due to the the issue of trapped air in the plumbing and the associated bleed points, expansion tank, blah blah. Also, hot water can be "zoned" with fan-forced heat exchangers in cabins with their own thermostats; more versatility, with more complexity. And, hot water systems use more electricity, with a motor that runs the burner and another one that runs the circ pump that moves the hot water - and then there are the fan motors in the heat exchangers, and so on. Hot water systems can also be incorporated with the engine's cooling system, and with the domestic water heater, so you can heat wash water with the furnace, heat the boat with the engine while underway under power, keep the engine at operating temperature with the furnace, and so on.

Condensation is always an issue if you live aboard, because the humans on the boat are the biggest source of moisture. We perspire and exhale an amazing amount of water, and it all ends up on the cold surfaces of the boat's interior. I lived aboard for eight years, and my condensation problems were immediately solved when I moved ashore. In colder climates, a forced air system will often draw its intake room air from the boat's interior because the heater doesn't have to work as hard re-heating interior air in really cold weather. But when it recirculates the interior air, it makes the condensation problem worse. Here in the Northwest, where winters are more moderate but pretty wet, condensation is reduced by drawing intake air from outside the living space (not from the engine space!). This creates slightly positive pressure inside the boat, and moisture is driven out through the boat's normal ventilation scheme.

I will leave the discussion of systems on larger yachts, which includes reverse-cycle air conditioning, twin-circuit hydronics systems, more sophisticated zoned air handling, etc. for another day, if that's okay...

One final thought just flashed on in the recesses of my brain: if you are installing a hot air system and it's a DIY project, be very careful with that big drill motor and the necessary large holesaws for making holes for ductwork. If you're reaching into a difficult space, and don't have a really strong grip on the tool, it can get away from you and rip the sh!t out of the surrounding area, and can easily and quickly break your wrist! Be safe out there!

I hope this treatise helps. If not, post here and tell me why - or for sure ask more questions if you like!

Strongsail, aka Captain Curmudgeon

[Jack Tyler]

Strong:

Thanks for the thorough comments. To the extent we have prior experience living aboard in truly cold winter climates, 3 years in Annapolis relying on an Espar system, I thought your comments were right on target. A couple of follow-ups...

We'd never consider heating with propane, not only for safety reasons but also limited fuel capacity. When cruising, you don't want to be looking for a propane distributor every week and I think that's what would be required in some months. I'm also disinclined to use a forced air system again. The comfort - and the delight of turning a thermostat dial! - were wonderful. But we found the Espar unit power hungry (when added to the other DC consumers, including refrigeration) and not very forgiving in operation once the demand voltage (what's coming out the end of the wire attached to the unit, given other DC systems operating) got near 12.0V. (I compare our previous Espar electrical draw with e.g. a Hella Turbo Fan, quiet and consuming .3 amps DC on low, and see a huge preference for the latter, electrically speaking). And finally, we'll be cruising the Northwest for a while, but then heading south where large investments in heating gear will earn heavy guffaws in the yachtie anchorages while we're still trying to repair the damage to our cruising kitty. So...where does that leave us? With a bulkhead installation using kerosene/diesel. And here's where a few more comments from you would really be helpful. Could you take a crack at each of the following questions?

1. Is there a brand (Force 10, Dickinson, Taylor, or fill in the blank...) that by design, burner type, support and/or safety considerations you think deserves a recommendation? Let's assume the (DIY, I'm sure) install is done carefully and we maintain the burner properly and we filter good fuel when we feed it...do one or more manufacturers deserve our business thru good product design/manufacturing/after sales support, in your experience?
2. For this type heater, is any ol' diesel fuel - properly filtered - good enough? Or do we elevate ourselves unknowingly into becoming kerosene connesieurs or raiding the local 'stove & chimney shops looking for pine scented lamp oil? I mean, we want the thing to be pretty forgiving on what it will burn cleanly...but are expecting too much?
3. It's unusual in my experience but occasionally a boat's layout will actually invite a cabin sole-level install of a bulkhead or stand-up heater. If that's an option, do you think it makes a big difference in heating performance to have it low-down, or can a well-directed fan accomplish pretty much the same thing. Our Espar outlets were all at sole level, which was a wonderful thing for the semi-frigid tootsies and is why I'm asking.

Thanks again for the thoughtful reply. Please...give us one more round!

Jack

[strongsail]

I can divide bulkhead heaters into 2 categories, I guess - ones that use the basic Primus-type burner and the ones that use a carburetor and a "smudgepot" combustion chamber.

The Primus burner is basically the same as is used in kerosene galley stoves. It won't work reliably on #2 (automotive) diesel but will work fine on "pearl weight" kerosene, which is sold as stove fuel and is pretty easy to find. The fuel tanks for these burners are usually pressure-type, with a built-in air pump or a regular tire valve that allows you to use a bicycle pump to pressurize the tank. This type of burner must be "primed" - it has a spirit cup that you fill with alcohol, light the alcohol and let it burn away, which pre-heats the burner and then the liquid kerosene is turned to vapor which produces a clean blue flame. Improper (impatient) priming will result in liquid kerosene being fed to the burner and results in "flare-ups," large momentary columns of yellow flame, smoke, stink, yuck. If properly primed every time, these burners work fine. If not, they are a major hazard. You also have to carry 2 fuels - kerosene and alcohol - and the alcohol must be dispensed into the spirit cup - I used to have a heater with a Primus burner on my Ericson 27 years ago, and I carried a liter of isopropyl alcohol in an aluminum backpacker's stove fuel bottle, and used a small (4-oz. or so) squirt bottle to dispense alcohol into the spirit cup. The kerosene was in a 2-1/2 gallon pressure tank with a tire valve under a settee near the heater - enough fuel to last all winter when daysailing. I suggest a tank without a pump because the built-in pump will at some point need rebuilding, and buying another cheap tire pump is easier.

The other type of burner is basically a little iron box with a controlled drip feeder and a combustion air control of some sort. This type of "smudgepot" works fine on #2 diesel, and is often plumbed to the engine fuel tank and fuel is fed with a little pulse pump - then you're back to needing 12 volts again - or it can be gravity-fed from a daytank above the level of the heater, which can be filled manually or from the engine fuel tank with a lift pump of some sort. These burners are started by turning on the fuel and letting a bit drip into the pot, then lighting a single square of toilet paper and dropping it into the pot and closing the door. They smoke quite a bit while warming up, and the flue often pukes soot on deck, but once the burner gets hot the exhaust is pretty clean. This setup needs regular maintenance (cleaning) to keep the firepot from becoming coked up with soot, ash, matchsticks, etcetera - if not kept clean, they can become a fire hazard as well.

Caveat: when shopping for "stove fuel" be sure you know what you're getting. White gas can be labeled as "stove fuel" too, and will give you quite a surprise if you use it in a Primus burner...

I won't recommend a particular brand of heater. If I do, and you buy it, and have a problem like burn your boat down, guess who you (or your insurance company's lawyers) will blame?

Who, me? Paranoid?

Yup. I work in the insurance business. Not goin' there.

Hope this helps, good luck to ya, ask more questions if you need to...

[Jack Tyler]

Strong:

More good poop; thanks very much. Coincidentally, I was cleaning out a locker today and came across just the type of fuel tank (for the primus type heater) that you describe; even had the little separate pump. Tore it out of our boat when we changed out stoves, from alcohol to propane.

You forgot to mention Tilly clips. Among their many 'quaint' customs, the Brits have perfected the use of odd/old/cheap/functional kerosene stoves like no one else I know of. And with most of my relatives from the UK, I should know. Tilly clips are little spring-loaded 2-pocket cups with asbestos lagging stuffed inside (don't you just love those Brits...) that are left soaking in a bottle of alcohol. When it's time to make tea, the clip is removed and clipped around the base of the burner. Strike a match and you get just the right amount of fuel heating up the burner base to vaporize the fuel and start the burner. That's when you burn your fingers and start dancing around the main cabin - right after removing the Tilly clip.

In fact, I found these clips to be THE solution to heating a primus burner, even in a rough seaway. There's really nothing to spill. And based on your descriptions, the primus burner sounds like the better choice, assuming the alcohol use is simple & safe. Which reminds me to ask: if you won't recommend a brand of heater (chicken...), how about advice on which burner type (primus or smudgepot) your prior customers found most desireable to use. I'm going to assume our finite cruising time in the NW makes obtaining the 'pearl weight' kero a non-issue, since we can bulk up occasionally. (Good point about 'stove fuel' sometimes being White Gas. In fact, I did use White Gas once on a boat...I found it remarkable how thoroughly the Purple K fire retardant penetrated every nook & cranny of the boat).

And finally - we're zeroing in on things here - I notice a huge difference between a Force 10 diesel/kero heater in my nearby WM catalog at 6,000 BTU and the bigger/more expensive Dickinson at up to 16,000 BTU. That one must toast the bulkheads and drive the crew in the cockpit. For that area, is the 6,000 BTU rating adequate for Spring/Fall heating in a 30-32 footer, would you think? Or put differently, what size boat would you want to see before recommending a 16,000 BUT unit. (Guess you can always throttle the Big Guy back, but the smaller unit is also easier to find room for).

Also, I notice the WM Dickinson blurb offers a fuel transfer pump when the fuel can't be gravity fed. Ah-ha! A sure sign the Dickinson is of smudge-pot heritage... See how your tutoring is paying off.

Thanks again, Strong. Appreciate the coaching - this is very helpful.

Jack

[Steve P]

I have a dickenson bulkhead heater.

Most of the details have been covered but I'll add some of my observations.

A circulating fan is neccesary to get the warm air up into the v-berth. There is a cold spot on the floor, perhaps another fan or a different aim on the current fan would help this.

With the heat going and the fan on pretty much all the condensation problems are eliminated.

We leave plenty of openings to avoid CO buildup.

I've had trouble with the flame blowing out in winds over 35knts or so. I think this would be improved if I got the T-shaped smoke hood instead of the round hood that I have. Even so I expect that at some point the wind will blow hard enough to put it out, so the combustion fan in the Dickenson is a real plus since it will keep the flame going in strong winds.

[strongsail]

Steve P makes a good point, since the smudgepot type has a lower combustion temp the stack velocity is less (thats why the flue diameter is greater too) and it's subject to backdrafts (smoking) and blowouts in gusty weather, and yes the H-shaped cap is better although you may have to rotate it based on wind direction to get it to work well, except at anchor when boat and cap reorient to the wind as one...and a combustion fan increases stack velocity so blowouts are less common.

Jack, your profile says you sail a Pearson 42 - that's a lotta boat for one Force 10 - a 16kbtu smudgepot may be a better choice since you have a larger boat and you may be able to actually fab a little hearth space with a metal backing plate (with airgap) and get the unit right down on the sole. Circ fan and louvers in cabin doors will help circulation - but there's always 2 Primus heaters! Choices, choices...but then I notice you are asking about a smaller boat in your post...??

[strongsail]

I have never heard of a Tilley clips, and since I sail a British boat, I feel I am seriously amiss. I shall do penance by Googling the thing and seeing what I get.

The Americans and the British: two cultures separated by a common language.

Every time I say the word "raspberry" I hear John Cleese saying it: "rawzbreh."

[Jack Tyler]

Strong:

A Pearson 424 now...but a smaller, different boat in the Pac NW, we think.

Jack

[CetaceaIV]

This isn't a very tecnical reply but it is my 2 cents for what it is worth.
I love our dickenson deisel heater. The little self propelled fan I bought last year was worth its weight in gold- well it was worth the $100.00Canadian. I find we don't need as much heat for and aft because when we are sleeping we have warm blankets and love the cooler air. Alongside we use electric blankets. But being a female I do find the toilet seat just a little shocking in in the winter. We also are lucky enough to have room for a dehumidifier when along side. It probably sucks a lot of air out of the harbour but it does keep things drier in here. We also light a kerosene lamp in the evenings that adds atmosphere and really seems to keep the windows clear.

[Jack Tyler]

L&E:

I really appreciated your reply as it reminded me of how much we enjoyed the heat, light and general ambiance of our large-wicked Den Hann Trawler Lamp when living aboard in Annapolis, MD - where it could get well below freezing and snowed multiple times each year.

Your preference for the Dickenson makes sense given the size of your boat and, if we keep WHOOSH, that would be our choice as well. (Provided I can fashion sufficient shields to keep our main cabin table from becoming toast). Were we to move down in size, I'd probably opt for the Force 10 model unless there was a space that invited the larger unit.

Don't worry about offering non-technical comments. Yours was just the type of reply I'm looking for!

Jack