Cabin Heating System

[rjm]

Heat out of an a4 kinda wimpy

I have ared Red dot hooked up for cabin heat and as stated before in an earler post it does work .. but the A4 just does not produce enough heat... my heater is in the middle of the boat and even with wrap over the heater hoses its just a slight warm never gets hot and prob would not keep up in colder weather
At best it seems a better raditor and heat exchanger than a heater my boat is a fwc boat and their must be better way..
it would prob do just as well to leave the engine door open and let what heat of the moter do the same thing..just my thoughts and am open to other options

[hanleyclifford]

The Red Dot heater needs to have 180 degree coolant AND a strong pump especially if the run is long. The MM 502 is the best coolant pump I've ever used.

[hanleyclifford]

If you are having trouble getting any heat out of your Red Dot heater, try routing the antifreeze to the heater directly from the exit on the manifold. I know this sounds unorthodox, but I run the coolant without any valves from the manifold to the Red Dot, thence to the hot water heater (engine exhanger inside), and finally to the exchangers. My only valve in the system is the bypass from the Dole thermostat. If you want to get anything out of the heater you must run a thermostat.

[lat 64]

My heater is just as Hanley suggests(see earlier post) except I have ball valves everywhere. They don't seem to affect the flow much. I get pretty good heat, but not like a car.
The engine runs at ~180, and I can divert more coolant to the heater if I want with the valves.

Getting the coolant temp up is key. If Hanley is correct that the Redot needs 180F, then a lot of raw-water-cooled boats will not work well for hooking up a cabin heater.

Winter is coming,
Russ

[hanleyclifford]

If I were going to build and market a cabin heater for the A4 fleet two considerations would be at the top of the list. First, the core should be all salt water compatible materials (the casing could be high temp plastic). Second, a shut off valve incorporated right handy at the unit. The valve need only shut off one hose if the heater is in it's own loop; this would have the effect of "dead ending" the heater without having to go into the engine room.

[rjm]

Engine Heater

Have an A4 Fwc with a Red Dot hooked up and works pretty good as a heater or an engine cooler..looking to figure out how to not have to keep re-adjusting the ball valve prior to the Hx and get the same heat from idle to full power any thoughts ..

[hanleyclifford]

Sounds like you have your heater in a separate (parallel) loop. How about an in line thermostat in the heater loop?

[rjm]

Engine Heater

Already have a thermostat ...do I remove the one on the engine and install a dole at my ball valve location

[hanleyclifford]

In order to get decent heat out of the heater first you need to stabilize water temp throughout the rpm range at 180 F. This might mean a different thermostat.

[ILikeRust]

My cabin heater is the little propane camp stove next to the sink. Which probably needs replacing at this point (the stove, not the sink).

[Bobgrif]

With a cabin heater using the cooling water from the engine means you have to run the engine for probably quite some time to make a difference in the cabin, seems a very expensive and environmentally unfriendly way to do it! Yes, if you've been running the engine for quite a while it will work but how often do we do that, especially when it's so cold you need to heat the cabin. Simple solution is to plug in at the dock and run an electric fan/heater.
In a previous boat I had one of these catalytic propane made-for-boats cabin heaters, bought from the UK, worked great!
Anybody know of a device that one can place on the stove burner (like a toaster) that works well to dissipate the heat?

Bob (sv 'Dovetale', C&C Corvette, Ontario, Canada)

[edwardc]

Anybody know of a device that one can place on the stove burner (like a toaster) that works well to dissipate the heat?

Bob (sv 'Dovetale', C&C Corvette, Ontario, Canada)

A couple of clay flowerpots, turned upside down, work great, especially if you can train a small cabin fan to blow air across them. The downside is that with propane stoves, the combustion process produces a lot of water vapor. This can result in every fiberglass surface dripping like a rain forest by morning!

[joe_db]

So do we have a heater?

[Vermont30]

Water to air heat exchanger. The A4 is the boiler and add a fan. Same principal as a hydronic heating system. Now, where to mount those
solar hot water evac tubes.

[Mo]

If looking for a heater one needs to be looking for something vented safe, installed safely, economical, will run when the engine isn't running and can be left running overnight in the boat. Engine heaters are not much of an option on a sailboat.

It's one thing to be nestled in a cove with a lantern going and it's able to keep the boat heated in the spring or fall...it's a completely different thing to be sailing and need heat for crew or family as the boat is underway, motion of the sea etc...especially in adverse conditions. That's really where a heater is needed.

Just this past weekend I was asked to go on a 100 mile ocean race and didn't go because they had enough crew. I went for a 40 mile ocean sail and followed the boys out. I was back at the dock at 5pm but the boys didn't make it back until the wee hours of the morning. It was warm when I was out there and winds were up to 18, then dropped off a bit as I was coming back in. Weather called for 30kts of wind and rain through the evening... they ran through it all the way home with it on the nose...said weather set in just after I made it back on the dock.

Was talking to the skipper and asked how they did...his answer was to the point. "We lost the race in the last 15 miles because we were all to cold to do a sail change" I couldn't believe the answer but they needed to put up a large jib as the wind died down...they'd run for hours in wind and rain...dark and stormy on a 47 footer! They all got wet and despite bringing sweaters, wet weather gear etc started to feel really cold and lethargic on the last leg.

I know he only told me that because he knows my background and I asked about warm gear and mentioned about staying warm and not waiting to get cold before putting on more clothes (that appeared to be the issue). I have to say I took it for granted that the boat has a heater but she's a racer...so every bit of weight counts. She may not have one installed...this same boat does the Newport to Bermuda (1st in her class 2 years ago and 2nd in her class this year)...not complete amateurs.

If anyone has ever been on a boat with a Webasto or Propane heater installed ( I have) there is some real heat that comes up out of the cabin and to the helmsman as well, very warm on the face. It is my humble opinion that the heater needs to be it's own entity, be able to kick some major BTU's for hypothermic sailors and not be tied in with the engine. I think it should have it's own dedicated supply of fuel as well.

FWIW I use a propane lantern on cool days with the hatch top open about 5 inches...it warms the boat. It would never do for a really cold night or ocean sailing where the temps drop down at night. I also have a propane Coleman Ceramic heater on the boat ... I find the lantern better.

I have been thinking of putting in a heater...it will be a diesel Webasto when I get around to it. Apparently you can buy the Webasto and install your own vent etc to make it marine. They have " marine" ones as well but apparently it can be done for under $1000.