Diesel Cabin Heater

We would like to install a diesel cabin heater and read with great interest an article we found here (or linked here) called "Sealing Deck Penetrations to prevent core rot" It was very good advice with regard to screw holes, but we are needing a 3" hole in our deck to accommodate a diesel cabin heater flue. We have a friend who put one in and now his gelcoat is crazing around the hole. Would anyone have any good advice as to how to apply the "Sealing deck penetrations" info to a 3" hole and how to prevent the crazing. Basically. we really want to do this the right way and go to school on someone who has done it right.

Thanks !

Sealing the deck core is simple matter of mixing up some epoxy and coating the exposed core. If you are really worried dremel/dig out the core a bit and fill with thickened epoxy to create a solid ring around the hole.

I considered a diesel heater for a long while but ended up with a Newport propane unit. I read every installation manual, twice and can't recall a 3" hole being needed, more like a 4" or 5" hole. The flues themselves are 3" and there needs to be a air gap around the hot flue pipe to keep from damaging the fiberglass. I would guess that your friend is overheating the fiberglass and this is causing the crazing you describe.

RT

I'm going to second Rob's input. I installed a Newport solid fuel (wood, charcoal, coal etc.) stove several years ago, and while I burn it on the conservative side and don't max out the fire size, I've never had any temperature in the surrounding cabin top structure. It is, I believe, a 5" inch hole for a 3" flue. I sealed the exposed core with epoxy as mentioned. Something I would recommend that is almost always needed anyway, is having a teak pad between the cabin top fitting and the deck. This is usually done to level the fittings anyway and adds another layer of insulation between metal and the deck structure.

Makes sense!

This all makes a lot of sense. We haven't purchased the diesel stove yet and so have not read all the literature that will come with it. What you both say makes a lot of sense and I will tell my friend Charlie, who may have to make his opening a bit bigger. I'm sure he knows about the epoxy part, but may need to open up a bit. Thanks again for the advice and pic!

Definitly not an expert......

I'm no expert on diesel heaters so my $.02 is may be worth that or less. My friend has an Espar diesel heater and it works great, with no stack required on deck. It is also very quiet. It does require DC power to operate. The Espar cycles on and off based on a thermostat and does kick down to more of a maintenance mode once the boat is warmed up. My underdtanding is that the exhaust exits via the same exhause outlet as the engine (I may be speaking beyond my 'expertise' here). Any way, off a sample of one this heater seems to work well. One of the distributors (of which I know nothing, just found it in a google search) is at http://www.boatelectric.com/espar1.htm

Good luck, if this is of any interest I can get more info on the install and operation experience from my friend next weekend.

Ac dc

Thanks, but the boat came with a reverse cycle Cruisar SXR12, 12,000 BTU air conditioning system that reverses to heat and I'm sure, works pretty good at a dock. The problem is that we will be cruising in Desolation Sound and beyond to Bella Bella on the west coast and will doubtfully ever tie to a dock. We had a diesel heater in our last boat and just loved it so that's what we're basing our choice on. By the way, we are wanting to take the air conditioning out and sell it. It was installed in 05 so it's pretty new if anyone out there is interested in buying it once we have it removed?

Here is a photo of the rudder hole through the cored cockpit. I hogged out the core material around the hole and the screw holes with a dremel and other implements then filled in with thickened epoxy. You should be able to do an identical process for the heater vent hole. Protect your core!

Just make sure you put some protective plastic below the hole when you do this, its messy.

I installed a Sigmar in my E38. The smallest one, which I chose, fit well but is undersized for winter in the Northwest. Also installed heatercraft (like a red dot) to use engine heat. It is absolutely fantastic, especially since we tend to run engines a bit up here. Heated my boat to 65 degrees in 20 minutes with ambient at 38 degrees. That cost about $200 with fittings to divert during the summer so I don't get any radiant heat.

As far as the core, I've simply used the bent nail trick. Bend a big finish nail at a right angle, the end length the distance you want to take out the core. Then put in a drill and it will strip out the core. Works for balsa, although I wouldn't use it on a plywood core. Amazingly clean and simple. Then fill with epoxy filler.