safe unattended heat

[davester]

I think I have a pretty good grasp of many of the merits (and drawbacks) of various heating options. But which heaters are best for times when the boat will be left unattended? These times would include being at work, away for a weekend, and possibly a week long vacation.

I am considering:
- bulkhead mounted diesel (sealed combustion chamber)... but I don't think these are supposed to be left burning unattended (though it seems like a lot of people do it). How safe/unsafe is this? What exactly happens if there is a blowback? Are there other dangers?
- forced air... These seem like good candidates for leaving unattended. Any opinions on this? Is it acceptible to the manufacturers?
- bulkhead mounted propane (sealed combustion chamber)... I would rather avoid propane, but I do currently have a propane stove, and a safe vented locker, so I might consider it.

My main concerns are safety, reliability, and liability (I would prefer not to violate the manufacturer's instructions as I would think this would have insurance implications if anything went wrong).

I am in the New York area, and will be heating a 33 foot boat with 3 cabins. I will be on the boat most nights... but I don't want to have to winterize the plumbing when I am away (I will probably winterize the engine as a precaution). The marina I am considering does not allow electric heat, although they might be ok with some low wattage heaters just to prevent freezing... if so, this might be an option.

Any opinions/experiences with this?
Thanks,
Dave

[btrayfors]

Dave:

Change your marina!

Seriously, as a veteran of 17 years liveaboard plus 6 winters my current boat has been in winter weather, I have concluded that by far the best and safest option is electric....provided it's done correctly.

The 17 years were on a houseboat. Tried most kinds of systems...kerosene, diesel, and several types of electric. Concluded that space heaters are dangerous...even the ones which are billed as "safe" (e.g., the little square ceramic heaters...I've seen 'em spit flames).

Finally went with the oil-filled heaters which look like radiators. NEVER operated them on the high setting (1,500 watts); always on 600 or 900 watt settings.

Modified one for special use in the engine room....removed the thermostat and switch and wired for 600 watts only. Put it between the big Crusader engines just in front of the Kohler generator, and left it on continuously in winter time.

On my present boat...a 42' sloop...I have two air conditioners which each have a 2,000 watt heating coil. Big one...about the diameter of your thumb. Just one of these keeps the boat above 55F (which is where I leave the thermostat in winter), except in the very coldest weather (0-10F with wind blowing). Then, I either use the 2nd one or fire up the Espar diesel heater.

Note that this strategy (electric) will only work where you have very reliable electric power, and have some sort of backup available.

Bill

[JohnRPollard]

Dave,

I would generally agree with Bill. For periods where you will be absent from the boat, some relatively low wattage electric/oil-filled heaters would probably be your best bet.

I know, for instance, that I would not leave our Dickinson Newport propane heater unattended during an absence of more than a few hours at most. I might feel a bit more comfortable with the diesel version -- but I just don't think the bulkhead style heaters are meant for extended usage when the owners are absent. (I'd have a bit more confidence in leaving the Espar/Webasto forced air heaters).

The nice thing about the electric option is that you can set them just high enough to keep from freezing -- which is all you need when you're away. Yes, you are in trouble with an extended power outage, but if you use the electric heaters to supplement a more self-sufficient heat source (such as a propane bulkhead heater) you will have some redundancy.

[tommays]

On Long island they get real pisssy about even leaving the boat pluged in during the winter IF your NOT onboard

[davester]

Thanks for the replies. I am not comitted to that marina, but it can be hard to find ones around here that accepts live-aboards. (I'll have another address, so not technically a live-aboard, but I don't want the marina complaining about how often I stay on the boat in the winter).

I don't know if this marina has a total ban on electric heat, or just wants to make sure everyone has another system- i'll find out. It does seem like the most simple, cost effective and redundant solution would be some low-power electric heaters to prevent freezing, and a dickinson bulkhead heater. I am curious, btrayfors, why you prefer using electric heat to your espar?

I would like a diesel heater partly so that I could use it while away from the dock. Also, I only have one 30amp circuit on the boat, but this should be enough to run a couple of low wattage heaters... Anyone know roughly how many watts are needed to just keep things from freezing?

[tommays]

If you look at land based fires in the winter electric space heaters all a leading cause

As far as electric heat i use TONS of electric drum heaters and heat guns (20+ units 24/7/365) and the plugs require a lot of care at 1000 watts and if we use 1500 watt units even the GOOD Hubble plugs have a high fail rate

[jira]

I run an oil filled radiator with a ceramic as a supplement and have been living aboard this way for 5 years. Note that you are better off without the electronic thermostat models as any power interruption will turn it off. Also note that the thermostats may not be spark protected. I would prefer to go with 2 radiators and forget the ceramic, but space is a bit if an issue, but I may try to make it work this year. I have each on separate 30 amp circuits, one directly to dockside via 10 ga. cable. Tommays is correct about the plugs, the resistance creates heat, particularly if the cabling is undersized.