Bay Cruiser Cabin Heater

[Peter Taylor]

Since I hope to use my BC20 on the occasional good day during the winter I have been looking at what sort of cabin heater I could use, e.g. while at anchor. I've chosen a "Pan 2000" which is designed to sit on top the stove - in my case an Origo Spirit Stove. The heater consists of an upside down stainless "pan" surmounted by an alloy heat exchanger through which a 12v computer fan blows air giving a warm air stream. The gases from the stove then go up through a pipe to be vented outside the cabin in an attempt to minimise humidity. It's a light and portable device so seems suitable for small boat use. The down side was the cost - over £400 by the time I had got it sent from Sweden - but thats still cheaper than fixed charcoal heaters.

So far (lacking a boat!) I've used it in my shed and I am impressed. For fuel for the stove I'm using low odour bio-ethanol to avoid the fumes and smell of meths. What smell there is reminds me of oil lamps used when camping and is not unpleasant. When I've actually used the heater in the boat I'll report how well it works!
Peter

[Tony]

Hi, Peter.
The BC20 is a great boat - and would probably be more popular if the BC23 price differential was larger - so congratulations on commissioning  No.9.
More cabin space than the BR Expedition and my Cardigan Bay Lugger, of course, and so more difficult to heat?
The CBL crawl-in-and-die cuddy has sitting headroom and is designed to sleep two ( Never tried it. You'd have to be VERY friendly and my wife doesn't "do" camping - or sailing on cold water, for that matter.) It is so well insulated that the only heating needed, even with snow on the cabin top, is a 2 litre hotwater bottle! I have a fleece covered number (ten quid from Boots the Chemists) which is still warm to the touch after 4-6 hours and, if left on a side shelf, warms the air in the cabin to a remarkable degree. However, I usually put it into the holdall containing my day clothing. The cabin air temperature only rises slightly as a result - perhaps I should splash out on a second one - but Oh! the joy of a warm shirt on a cold morning!  After a brew-up the kettle goes on again and the hotwater bottle goes back in the holdall with the sleeping bag and tracksuit, which makes turning in after the pub a more relaxing experience. 
Incidentally, I NEVER use a stove in the cabin, only outside on the side decks, ( sheltered by the spray hood if it's raining) for the following reasons:-
Spillages. Powerboat wash cannot be predicted and a mess in the cockpit is easier to deal with.
Nowhere to leap to in a small cabin, either, and you don't want the kettle in your lap!
Carbon monoxide and condensation are not problems in the open.
Smell. I love a good curry but if the cabin and everything in it still smells of fried onions and tamarind 3 days later.....
Fire. If something goes wrong in a cabin there is only one way out!
The BC 20 cabin is large enough for most of the above not to apply, perhaps, but I've been on 54 footers where all of them do!
One last point. Anyone who has ever had to sleep on a small boat in a gale will tell you that a BC 20 beats a BR20 hands down! No boat tent made can cope with driving horizontal rain!

[Julian Swindell]

I would agree with Tony on not using the cooker inside, even on a BC20. I have done so, both with camping gas and alcohol and the smell from the latter is awful and the amount of condensation, both from the fuel and whatever you are heating, is scarily considerable. The risk of CO poisoning is very genuine and probably far more significant that the risk of drowning which we have been chewing over recently. As a little example. I am a very fortunate person in that I very rarely get headaches, even when I've got streaming colds. But one morning this summer on my boat I woke up with a a real thumper, which was quite worrying. I wondered if something awful had happened to me. Then I noticed that I had left the cabin oil lamp lit, just very low, overnight. That had generated sufficient CO to make me feel dreadful just after a few hours. It had never happened before, even though I had left the lamp lit many times but I realised that on that night it had been cold and I had closed the hatch. I hardly ever light the lamp now and rely on boring looking but safe LED cabin lights. And I always leave the hatch open under the spray hood.

On cabin heating, I did toy with the idea of a charcoal heater, but basically, if it is cold enough to need heating, it's not warm enough to go sailing for me. I'm a summer sailor and winter shed man.

[Peter Taylor]

I agree on always cooking outside the cabin, mainly to avoid cooking smells and, above all, not to add even more humidity to the air! After all, when camping I never cook in the tent.

But the important feature of using the pan2000 with the spirit stove as a cabin heater is that the stove exhaust gases are led outside the cabin.  I'm attaching some photos (taken on my jetty). The first shows the stove/heater combination. The stove in gimbals is bolted to a metal tray which can be secured in the cockpit for cooking. As a heater (with gimbals down) the pan2000 is clamped on top of the stove with the flue going to an outlet in the cabin roof.

The second photo shows the back of the pan2000 with computer fan and the buzzer which warns you if the heat exchanger is over-heating (e.g. if the fan has broken). The third shows the supplied outlet for the cabin roof in closed off state. I have a metal rain cowl which slots into it when in use. With the stove burning in the cabin you also need to ensure some ventilation is available to replace the consumed oxygen! I plan to install a closable vent in one of the washboards.

The low-odour bio-ethanol (from Contemporary Elements) is pricey at £3 per litre delivered (if you buy 20l) but I think well worth it for the lack of smell. I would never use the heater when sleeping, and I do have a CO alarm. Incidentally the latter was much cheaper from the Force 4 chandlers than from the local B&Q!

Of course all this is hypothetical since I don't have the boat yet, but trials in the shed on my jetty seem promising!
Peter

[Peter Taylor]

I thought I'd provide an update on this old thread since I've made some progress!  The Pan200 worked fine in my shed but when I tried it in Seatern last winter the CO alarm soon went off. It seemed that the stove was not venting through the cabin roof probably because I now had a shorter stove pipe plus the effects of air flow over the hull and cabin. Since I wasn't sleeping in Seatern I put the project on hold!

This year I've had a chimney made up and also incorporated a computer fan in the exhaust pipe (the exhaust gases are only warm not hot after they leave the heat exchanger - part of the problem in getting an up draft). Switching the fan on for just a few minutes to establish the flow while the pipe and chimney warms seems to work well. Any longer and the gases are drawn too rapidly through the heat exchanger. Best of all, the CO alarm detected no CO (it has a digital concentration display) indicating that all the exhaust gases (including water vapour as well as CO) are now vented outside the cabin. I've only had a couple of test runs so don't know how it will work for all wind directions, but it seems promising

The heat output (using a spirit stove on low setting 2) should be enough for the BC20 cabin which it warmed by 4C in 30 minutes (despite rain and wind outside).  I'm not sure about a BC23 although you might be able to turn the heating up more if you are using gas. The limit with the spirit stove is caused by trying to avoid soot forming in the heat exchanger. However the latter doesn't seem a problem so far! Incidentally the low-odour bio-ethanol lives up to its name - no smell at all even when used to boil a kettle.

Photos of the chimney and the test set-up attached. The chimney screws into the through roof fitting and a blanking cap (with o-ring seal) covers it when not in use. More details on my Seatern Blog (under November 2014).
Peter

[Tony]

Hi, Peter
That boat heater looks like a serious bit of kit !
Makes my hot water bottle look - well - sort of primitive.
It does have one advantage, though. You can stuff it down the front of your drysuit when actually sailing. (Just don't fall overboard - and remember to remove it before returning to the club house. Tends to cause comment.)

[Jeremy Andrews]

I thought I would add a different experience. My BC20 No 6 (Jaunty) follows after an Etap 20 , Etap 23 and Red Fox 200 over the last 25 years and heat and light over that time has, and still is provided by a 35 year old Tilley Lamp  and an Origo Heat Pal running on bio fuel. Heat Pal doubles as a second "simmering station" to supplement a portable gas stove and the Tilley provides enough heat for most of the season as well as light. This combination has worked well throughout the quarter century with a relatively recent addition of LED cabin and nav lights . Power for lights and instruments comes from a pair of gel batteries that are small enough (12  and 20 ah) to be recharged at home every now and again. A dedicated 20 ah battery in a waterproof wooden case underneath the cockpit side deck drives an autohelm avoiding messy wiring.
Jeremy Andrews

[Peter Taylor]

I thought I would add a different experience. My BC20 No 6 (Jaunty) follows after an Etap 20 , Etap 23 and Red Fox 200 over the last 25 years and heat and light over that time has, and still is provided by a 35 year old Tilley Lamp  and an Origo Heat Pal running on bio fuel.

But do use the boat in winter and if so, don't the Heat Pal and Tilley Lamp add to moisture and CO problems in the cabin?

Meanwhile, after sleeping on the boat during much of the last few weeks (!), I've finally solved all the problems with the PAL2000 heater by swapping the heat source from bio-ethanol to one of those flat "butane" stoves. The butane stove (indoor type with gas cutoff if flame goes out)  runs hot enough to prevent back-draughts and condensation without causing soot in the heat exchanger. So far I've tested it with an outside temperature down to 3C and (on a different occasion) during a gale. The inside of my BC20 quickly becomes comfortably warm and it would heat a BC23 easily. The CO alarm registers no CO on it's digital display.  Only downside is the initial cost for stove and chimney! For anyone interested in installing a PAN2000 I recommend the  November 2014 entries and my "end of first year summary" in my Seatern Blog.

The final problem is that even the 220gm "butane" cartridges (that contain some added propane) don't perform well below 5C. I've taken to keeping one in my sleeping bag at night! ...maybe there is a use for Tony's hot water bottle to warm my gas cartridge!

Peter

[Jeremy Andrews]

In answer to Peter Taylor, no I don't "frostbite" as I live in the Thames Valley with the boat under cover, but even in April chills I haven't had problems and  I'm still here to tell the tale, thanks to through ventilation and Matt's first BC20  cockpit tent!

[Peter Taylor]

Since I keep mentioning the Pan2000 cabin heater in this thread and also the "Butane stove" thread (possibly ad nauseam!), I thought I'd post some photos of my "final" installation which seems to work very well. In the cabin forepeak photo I've indicated how the heater swings out of the way allowing the cooker, and the base I've made for it, to be packed away when sailing. With the photo of the chimney I've included a sketch of the way I've insulated the exhaust where it goes through the cabin roof.  This is (I hope) over-kill since when using the heater you can grasp the metal parts of the roof fitting which are warm but not hot.  In fact the greater problem is keeping the chimney warm enough to avoid condensation which is why it has yellow scaffolding lagging fastened around it.  When sailing the chimney unscrews and is replaced with a flush cap. 

The heater didn't work so well when I tried to use it on my Origo spirit stove and I tried things like an exhaust fan and condensation trap, but using the gas stove the whole installation is much simpler and I am very pleased with it. With this setup my digital CO alarm has yet to show any CO within the cabin, even in cold, windy conditions.

Peter