Boat heating wish list

[GILow]

Hi all,

I am well into building my boat heating system, based on ColdEh's excellent ideas here:

http://www.cruisersforum.com/forums/...er-149641.html

I'm getting to the pointy end now, the furnace, buffer tank and hot water system are together, and I now have started to wonder how I will configure the heating of the boat.

This is a call to any of you who would like to share your wisdom/frustrations/advice on boat heating. What worked for you? What didn't work? What do you wish you'd done differently or what have you seen on other boats and really wish you'd incorporated into your system?

For the record, I have 5kW of heat available in hydronic form. The boat is a flush deck 42 footer which is pretty well stripped out, so putting in the hoses to heat various areas is very easy right now, but will get harder later.

Although I will be in some warm places initially, I will be moving south to Tasmania to live and work so heating needs to be VERY, VERY good indeed.

Sophisticated electronic control systems are very much my forte, so if you think of something that would require complex management, that may be possible, even simple.

Over to the brains trust.

Matt

[Pete7]

Matt,

I know it's easy spending someone else's money, but do you have a back up plan when it all goes pear shaped at mid-night with a howling storm outside and lashing down with rain?

How will you turn the air over to reduce condensation? how about one of those oil fired Dickinson heaters as well?

[coopec43]

Matt


Maybe a stupid suggestion but what happens to the heat from your fridge/freezer? Where do you duct that? (Maybe you won't need fridge/freezer in Tasmania? )


I haven't done any sums but would a wind generator provide any heat running 24/7? (Of course there would be no shortage of wind down there)

[GILow]

Originally Posted by Pete7

Matt,

I know it's easy spending someone else's money, but do you have a back up plan when it all goes pear shaped at mid-night with a howling storm outside and lashing down with rain?

How will you turn the air over to reduce condensation? how about one of those oil fired Dickinson heaters as well?

A very good point about fall-back. In theory at least, I will be at a marina in Tasmania with 240v power. Electricity is an expensive but practical way to heat the boat, so I guess keeping a column heater somewhere on board would be wise. I am actually looking at incorporating a 240 v heater element into the buffer tank on the basis that this would act as a backup for the diesel furnace.

Condensation is something I am worried about. I figure I'll just have to see what happens and respond accordingly. A bit of reading to do there.

The Dickinsons are very good, but it's another hole in deck for the flue... a bit of a big step....

[GILow]

Originally Posted by coopec43

Matt


Maybe a stupid suggestion but what happens to the heat from your fridge/freezer? Where do you duct that? (Maybe you won't need fridge/freezer in Tasmania? )

Fridge in Tassie won't be working hard, that's for sure. Fridge will be an Ozefridge, so too efficient to produce much heat waste anyway.
.

[cj88]

Seeing as it's stripped out, what are you doing for insulation? I'd also think about some sort of removable/temporary double glazing to help reduce condensation during the Tassie winter. If I was on the hook I'd probably also consider the Refleks diesel heater as a backup but in a marina, it's just so easy to just plug in an electric heater as a backup instead.

[tkeithlu]

We are very satisfied with our Dickenson type stainless steel miniature fireplace, which in our case runs off propane. Better might be a diesel model. It's very attractive, takes up very little space, and the concentric piping isolates the air in and chimney gas out from air in the boat. Lots of heat is claimable from running that concentric pipe inside the boat up to the deck mushroom.

Living on the boat for 2 1/2 years in North Florida hardly qualifies as Tasmania, but it does keep the main salon toasty in 30 degree Fahrenheit waether.

[GILow]

Originally Posted by cj88

Seeing as it's stripped out, what are you doing for insulation? I'd also think about some sort of removable/temporary double glazing to help reduce condensation during the Tassie winter. If I was on the hook I'd probably also consider the Refleks diesel heater as a backup but in a marina, it's just so easy to just plug in an electric heater as a backup instead.

Yeah, insulation has me scratching my head. I am tempted to see how she goes without it. I may regret this.

My reasoning is, the hull is AT LEAST 27mm thick above the waterline (actually, about 39mm at the waterline) and the deck is 37 mm thick. My limited experience of over-night stays in winter have left me surprised at how warm I was with no heating at all.

It's a gamble, but at least most of the hull will remain accessible after the fitout if I am wrong.

[Ray-Dianna]

We keep our sailboat at Campbell River, BC, it can get to to 0ºF or lower and remain there for 1-2 months. We use the shrink plastic and double sided tape on all ports and hatches to prevent condensation there. We also applied double reflective bubble insulation on all surfaces to help with keeping cold out and reflecting the warm air back into boat. We also use a de-humidifier (best idea) to reduce remaining moisture thru out the boat. The boat is heated with the espar D4 heater on a 37 footer.
If you have the chance to apply insulation, do it now.

[stormalong]

Condensation will be an issue simply because you are living aboard. Breathing, cooking and showering all add moisture to the air. Consider a room size portable dehumidifier. I did that for a few years and it made a world of difference. Drain the condensate into the bilge and let the automatic bilge pump deal with it.

You said your hull is very thick. What is it's composition? Foam core might help. Closed cell foam sheet is available in various thicknesses. While the interior is out it is a great time to do this. I have 1/4 inch that was installed when the boat was built but I would go at least twice that, more if possible.

[bcboomer]

I used 3/4" pex hydronic tubing and Sea Tech quick connect fittings.
Because the storage areas behind the settees etc all go below the waterline, I ran the supply and return lines in the bottom of these. That eliminated the perpetual damp.
I configured the feed/return in parallel but don't think it was worth the effort in a small boat.
One return line, after the heat exchanger, is 3/4" copper and run under the floor where we sit for meals. Really nice on chilly mornings.
The head is heated via a heated towel bar. If you go that route be sure you really flush it well.

[ausnp84]

Yep, I’d second fitting closed cell foam insulation to cut down condensation. Fitted the 25mm version in my steel ketch and never, ever had condensation, even living aboard in grim UK winters.

N

[NorthCoastJoe]

I have never setup hydronic boat heating but have done a few houses. In concrete floors 1/2" pex is just layed on the rebar and buried in the concrete. It gives nice even heat. If you do not insulate your pex tubing the heat loss will be spread out along the run. There are clip on fins for pex tubing when used under wooden floors that might also be a good choice.

https://www.houseneeds.com/heating/r...ransfer-plates

We heat our house with a wood stove and when its cold nothing beats standing in front of the wood stove to take the chill off. Love to hear how it works out.

[Pete7]

Originally Posted by GILow

Yeah, insulation has me scratching my head. I am tempted to see how she goes without it. I may regret this.

We lived on board for a month in Feb 18, one of the coldest in the UK for several decades. Tins of food in the lockers were running with condensation as was the inside of the GRP hull. 48 hours later with the Airtop blown heater dried things out somewhat by taking cold dry air from outside, heating it and forcing damp air inside out through the vents. However, I did have to take the floors up to mop up in what has always been a dry boat.

To take the beautiful furniture out is going to damage it hence why I haven't insulated the hull. If you can, then do add closed cell foam insulation to as much of the hull as you can. Finally think about carpet mats for the floors. We have them to stop the dog scratching the varnished floor and that helped to insulate the boat too.

Pete

[DeepFrz]

Originally Posted by GILow

Yeah, insulation has me scratching my head. I am tempted to see how she goes without it. I may regret this.

My reasoning is, the hull is AT LEAST 27mm thick above the waterline (actually, about 39mm at the waterline) and the deck is 37 mm thick. My limited experience of over-night stays in winter have left me surprised at how warm I was with no heating at all.

It's a gamble, but at least most of the hull will remain accessible after the fitout if I am wrong.

Oh, no, don't do this. Insulation is very important in a cold or hot climate. There are plenty of threads on CF on this subject. Insulation - ventilation - HVAC. They work hand in hand.