Trawler Heating

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bigbeartr57

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My wife and I are moving to San Diego and have decided to take the plunge and live aboard. We've narrowed it down to some favorite boats in the 38-42 ft range, but none have heating or AC. After some research and advice from our broker, we've determined that AC isn't really necessary, and that if/when we need it, a portable solution would work just fine, so no issues there. The consensus on heat, on the other hand, is a different story. It doesn't get frigid cold in San Diego, but cold enough to make the investment worthwhile. I think many people get away with portable heaters, but we are expecting our first baby soon, and would prefer a permanent solution that would be safer and also provide a more constant temperature throughout the boat. Big Question: What advice do yall have on boat heating systems? We plan to spend most of our time (probably all of the time that heat is required) in a slip with reliable electricity constantly available, but electric heaters don't seem to be very popular for whatever reason (thoughts?). Cost is always a consideration, but not a limitation.
 
Heat pump.
That's what marine water cooled air conditioners are. They pull heat out of the boat and pump it into the water. Almost all have the reverse cycle for heating. They pull heat out of the water and pump it into the boat. These units are far more efficient than electric heaters with regard to power consumption relative to BTU output into the boat. They work extremely well down to 50 degree water temperatures, very well down to 40, and still produce heat at 35 degrees..

Ted
 
Installing a King Pic a watt heater will be the simplest most economical way to go for a boat that lives in a fairly warm climate and spends most its time on the dock. It is however, utterly worthless if you want to spend time on the anchor with out listening to a generator.

Frankly, I see no reason why you couldn’t get by with 2 small space heaters but you are correct, they are not nearly as safe as a proper marine quality heater like King’s Pic a watt.

There are various levels of diesel heaters, all have their strengths and weaknesses. One would have to know more about your needs and budget in order to make a quality recommendation.

I would avoid propane unless there was a specific reason to avoid diesel.
 
I second Ted's suggestion on a heat pump. To put only heat in would be short sighted in my opinion. On our last boat we didn't think we needed air conditioning but those few days a year when you get hot humid air with no breeze sure changes your mind after a sleepless night. Fans help marginally. Resale is another factor in that selling a boat with both heat and AC will bring more buyers and likely a better price. Good luck with whatever you decide on.
 
I have a 38’ sedan bridge it has built-in King heaters in each berth and 1 in the solon/galley area. I’am on the upper Mississippi and stay onboard 9 months of the year, I’am comfortable with 2 heaters down to the mid teens. 1 in either berth will almost run you out on the lowest thermostat setting. The boat will have to be wired properly to use electric heat, mine has twin 30 amp inlets.
 
I had a boat in Los Angeles. When I bought it, it had fan-forced electric wall heaters similar to ones you'd buy at home depot or lowe's for home use in the salon and aft cabin. From the looks of them, they were installed in the 1970s or 1980s. They still worked fine in all respects, though.

Eventually, I added a reverse-cycle marine HVAC system to the boat for the hot summer days. I also installed a panel heater (https://www.amazon.com/Amaze-Heater-250SS-HG-Electric-Mounted) and a line-level thermostat in the forward cabin, just as an experiment.

So, I had plenty of options. But, as it turns out here is how it broke down for me:
-- Marine reverse cycle HVAC: Great for cooling the boat on hot summer days.
-- Electric wall heaters: Preferred solution for the coldest days of the year. Relatively quiet. Could run both off of shore power. Could heat the boat even on the coldest days. But, of course, electric space heaters are fire concerns w.r.t. combustibles nearby, etc.
-- Panel heater in forward cabin: It couldn't change the temperature in the cabin much or quickly, but if turned on in the evening could keep it from dropping much overnight. I'd say it could hold it about 10 degrees above outdoor temperature and slow the fall more than that. It was nice, though, in that it was dead silent, took up virtually no space, wasn't a fire or burn hazard, and was low enough power to run for guests all nice off of the inverter. I might go with the 400W if I'd do it again.

But, my favorite option of all was....electric blankets. At a 10/10 setting they would take about 150-200W each, depending upon which one. But, in reality, I set them for 3-4 and they would take only 45-65W each. With that little power consumption, i could run 3 of them all night off of the inverter for me and guests and still have enough energy left in the batteries to get me through the day (I'd run the inverter to charge up at dinner time every night). No problem.

If you are wondering why I didn't use the marine AC unit to heat, it is just because it was louder than the electric heaters, so I preferred them. And, I guess I always worried about it sucking in some trash unattended overnight (even though it was a newer one with logic to shut itself down in this case).

So, in the end...for cooling I used the reverse-cycle AC unit. For warmth on cool nights, I used electric blankets (even a throw for the settee). And on the very, very few really cold nights, I used electric fan-forced wall heaters. I didn't really use the marine unit to heat, except occasionally just to prove it still could. The panel heater was a novelty.

In Florida, where I am now, a lot of people have portable home units in their boats to fight the humidity and keep things cool, while avoiding the risks I mentioned w.r.t. marine units in floridas very shallow slips. Then, they switch over to the marine units when underway.

As for how to how to handle a new born...I can't help you there. But, maybe some of this applies in some way.
 
I hadn't considered a heat pump. I'll definitely look into it. Are they very difficult to install?
I would say the difficulty level would be above the comfort level of 75% of boat owners. The installation requires installing a through hull fitting below the water line and one above the water line. If you feel comfortable doing that part, most of the rest will probably fall within your comfort level.

Ted
 
I kept a sailboat on Shelter Island for a few years and drove down from Newport Beach where we lived. Admittedly we never went on lousy weather days, at least no cold ones, but I never remember needing heat and never air conditioning. I realize that full time live aboards would catch a few cloudy and cold days so heat would be necessary.

The cheapest solution (under $100) are a couple of electric space heaters. A single 30A shore power system will be maxed out with two but you probably only need one 99% of the time. A 240/120V 50A shore pwer system won't have any problem with two. Two 1,500 watt heaters produces about 10,000 btu/hr.

The next step would be a 16,000 btu (or even 12,000 btu) reverse cycle air conditioner. These will be about three times more efficient while heating than the space heaters, ie use less KWhrs, but will cost $3-5,000 installed. This would be my choice.


Edit to answer the OP's question: You can do most of the installation yourself but you are likely going to need to haul out to add a thru hull for the raw water supply. Every thing else is straight forward mechanical installation and running a 20A circuit to power it. I helped a friend install one and it took us maybe 8 hours ex thru hull installation.


Finally and you don't want to go there are diesel heaters: bulkhead mounted drip burners, forced air systems and the cat's meow- a hydronic system. These start at $2-3,000 installed for the drip burner and the forced air system and go up to $5,000+ for the hydronic systems.

David
 
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I have reverse cycle heat pumps. They put out great heat and AC. They are very efficient. They most certainly add to the value of the boat. As OC said, installation is a bit intimidating. My only complaint with my heat pumps is the noise. Fine by day but they wake you up at night when they cycle. The noise has a lot to do with were the compressor is located.

Nothing puts out heat like a diesel furnace but since the OP is in San Diego, I don’t see much value in diesel for him.
 
Electric is cheap installs easily, doesn't require thru hulls and since San Diego never really gets cold a failure of the power supply will not sink the boat or kill the crew.


FIRE is a danger so heaters with good overheat protection are required.
 
If I were going to use electric heaters (which wouldn't be my preference for long term solution) they would be residential oil filled portable radiators. The fire risk is almost absolute zero. They are quite (no fan), and have a tip over safety switch.

Ted
 
I have a Dickenson Lofoten heater for sale in classified no boats. New and never installed.
Mike
Baton Rouge, LA
 
Another option would be a forced air heater like Wabsco. If you are somewhat handy the installation is not that difficult. Sure marine in Seattle is a great resource for this product. I’ve had one for twenty years and i’m Happy with its performance. Cost would be in the are of $3500.
 
... we've determined that AC isn't really necessary, and that if/when we need it, a portable solution would work just fine... The consensus on heat, on the other hand, is a different story. It doesn't get frigid cold in San Diego, but cold enough to make the investment worthwhile... What advice do yall have on boat heating systems? We plan to spend most of our time (probably all of the time that heat is required) in a slip with reliable electricity constantly available, but electric heaters don't seem to be very popular for whatever reason (thoughts?). Cost is always a consideration, but not a limitation.

I lived onboard for several years in Newport and Huntington Harbors. I had electric heat but no aircon. Yes I had an onboard fire from the (old) electric heaters. Glad I never ran them when not onboard (please learn from this!)

But for a new install they're fine at the dock. Probably best and cheapest solution for you.

Not having aircon... well it was uncomfortable many times during the summer, so I tinted my salon windows. Wish I had insulation in that boat, that would have helped. But aircon was not necessary, only a convenience. Consider opening up your headliners and adding a layer of insulation.

Sitting dockside is different than anchored or cruising. On the left coast I don't think you need aircon if you're actively cruising, but if you wish to travel up north at some point in the future then you need a reliable source of heat. A simple diesel bulkhead heater and some small electric fans might be good enough. Total investment perhaps $1k. Easy to install by yourself.

My best advice is just buy a couple of oil-electric heaters from WalMart for now. Use the boat for some time before deciding to spend $5-10k for aircon or another expensive solution. But the insulation thing is important on overheads, hull, anywhere you can reach.
 
Makobuilders,

Thanks for your posting. Any chance you can elaborate on the specific cause of the fire and how you put it out. And, if there was a way you think it could have been prevented?

Thanks!
 
The wiring was 40 years old, the good ole fashioned asbestos insulated stuff. Asbestos really is a great insulator - except for that minor white lung disease thing :)

Anyway it was where the wire connected to the 40 year old bulkhead mount electric resistance heater. It was at the connection is all I remember. Mounted to my wood bulkhead. Luckily my smoke detector sounded while I was sleeping. So I cut the electricity and smothered the flame. Relatively minor, so I didn't mean to give the impression that the whole boat burnt down, although it could have been that serious if I wasn't onboard.

Electrical fires are nothing to be complacent about. Here in this 3rd world country we see them all the time and they get bad. It seems that every kid some kid dies because the split aircon unit burns, and they are always mounted above the bed. These villas are built out of concrete, so that gives you an idea of how bad it would be on a boat.

Anyway, I still stand behind my advice given previously.

BTW, your child should have a truly adventurous and memorable life growing up on a boat. Best of luck to you.
 
My wife and I are moving to San Diego and have decided to take the plunge and live aboard. We've narrowed it down to some favorite boats in the 38-42 ft range, but none have heating or AC.......but we are expecting our first baby soon......

Not to derail the question as it is a good discussion but...moving aboard a 38-42 boat and having your first baby...at the same time. You are a brave couple. Can't imagine doing this. Pack N' Play, high chair, bottles, I guess others have done it so good luck to the three of you!
 
I second Ted's suggestion on a heat pump. To put only heat in would be short sighted in my opinion. On our last boat we didn't think we needed air conditioning but those few days a year when you get hot humid air with no breeze sure changes your mind after a sleepless night. Fans help marginally. Resale is another factor in that selling a boat with both heat and AC will bring more buyers and likely a better price. Good luck with whatever you decide on.

I third these opinions.
In fact, i'm sure you'll find you use AC more than heat.
It's worth the investment and if you sell the boat, it will fetch more.
 
on the through hull problem for a reverse cycle unit. if you raw water head you could use the feed for it and possibly share it or just switch to a freshwater flush head.
 
If you're going to run portable electric heaters, make sure the wiring supports them. Also the standard 120v 15 amp plugins can be replaced with ones rated for 20 amps. Lots of people burn out the sockets and heater plugs because the sockets can't take a constant 15 amps.
Marina voltage isn't always proper voltage. In the winter with many using electric heat, the voltage can go down. The appliance then draws more amps to make the wattage.
The best uniform heat throughout the boat is hydronic (In my opinion). Usually with a diesel fired unit and baseboards or radiators and divided into zones, each with it's own thermostat gives you house like comfort. I heat an 83' boat hydronically and can have the whole boat whatever temp I want. Although for economy, I usually keep unused areas about 60°F. My winters are usually in the 40°s but can be zero.
 
on the through hull problem for a reverse cycle unit. if you raw water head you could use the feed for it and possibly share it or just switch to a freshwater flush head.


It is not a good idea to share a thru hull with the A/C's raw water pump. These pumps are often not self priming and any air sucked back in from the head can cause an air block.


David
 
If you're going to run portable electric heaters, make sure the wiring supports them. Also the standard 120v 15 amp plugins can be replaced with ones rated for 20 amps. Lots of people burn out the sockets and heater plugs because the sockets can't take a constant 15 amps.

That violates the NEC and I suspect a 20 amp socket (the one with the cross bar on one of the legs) doesn't support any more current than the 15 amp ones.

The reason it violates NEC is that you could potentially plug in a 20 amp appliance (with a cross bar lug) and trip the 15A breaker that supplies it as well as cause an excessive voltage drop due the 14 gauge wire rather than the 12 gauge wire required for 20A circuits.

Edit: If you want to change to a 20A socket, also change the breaker to 20A and upgrade all of the wiring from that breaker (and any downstream from that outlet) to 12 gauge.

David
 
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Well, he did say "make sure the wiring supports them." I interpreted that to mean that you should add appropriate wiring, as well as the 20 amp sockets. I would hope that it would go without saying (but realize it probably doesn't) that just sticking a 20 amp socket on a circuit that is wired and fused for 15 amps would be a bad idea.
 
Not to derail the question as it is a good discussion but...moving aboard a 38-42 boat and having your first baby...at the same time. You are a brave couple. Can't imagine doing this. Pack N' Play, high chair, bottles, I guess others have done it so good luck to the three of you!


This quote brought back memories....


We brought our first born daughter back to the boat directly from the hospital. She grew up and took her first steps on the boat ( GB36 ). The Admiral still moans about carting the kid in a baby bucket.. and the laundry down the long walk from the car to the boat. Boats arn't as easily kid friendly as houses.. but we still had a grand time those first three years.


We did fight heat issues the first winter with a 30a electrical service and a cranky Webasto heater. Finally resorted to a 50/50 blend of diesel and kerosene to lessen issues. Looking back I believe it was a combination of low voltage and old fuel that was the culprit.


To the O.P.
To this day our daughter that grew up on the boat has way more of a closer connection to boats that the second that came home to a dirt home. The Admiral did put her foot down though and there was no way she was raising two kids on the boat, moved into a new home a month prior to arrival of #2.


SoCal is way more weather liveaboard friendly than Washington.. walking down the dock ..in the snow with a infant and all the associated stuff was a p.i.t.a.
HOLLYWOOD
 
Not to derail the question as it is a good discussion but...moving aboard a 38-42 boat and having your first baby...at the same time. You are a brave couple. Can't imagine doing this. Pack N' Play, high chair, bottles, I guess others have done it so good luck to the three of you!

It'll be an adventure for sure! I've always wanted to live on a sailboat. The wife likes the idea too, but not so sure about the sailboat. She is 100% on board (pun intended) with the trawler lifestyle though. We were already considering it for our next home, and when we found out we were being stationed in San Diego (biggest live aboard community in the world for A LOT of reasons), we had to jump at the opportunity. The cost savings will be enormous compared to apartments with even less space than a boat. We also kinda figured that, worst case scenario, the life style isn't right for our family and we can move ashore and at least say we tried. It's not like we are eliminating our options.

Throwing the baby into the mix does change the equation a bit, but we are still excited to start both adventures at the same time. We are thinking about starting a YouTube vlog to document the adventures. Vlogs like that have been a wonderful resource to us in the past and God knows we would've loved a resource like that before jumping into this double adventure head first.
 
on the through hull problem for a reverse cycle unit. if you raw water head you could use the feed for it and possibly share it or just switch to a freshwater flush head.

I was actually thinking something like that might be a good option. At least temporarily until my next regular haul out for a bottom job, when I could add a through hull without the extra haul out expense.
 
This quote brought back memories....


We brought our first born daughter back to the boat directly from the hospital. She grew up and took her first steps on the boat ( GB36 ). The Admiral still moans about carting the kid in a baby bucket.. and the laundry down the long walk from the car to the boat. Boats arn't as easily kid friendly as houses.. but we still had a grand time those first three years.


We did fight heat issues the first winter with a 30a electrical service and a cranky Webasto heater. Finally resorted to a 50/50 blend of diesel and kerosene to lessen issues. Looking back I believe it was a combination of low voltage and old fuel that was the culprit.


To the O.P.
To this day our daughter that grew up on the boat has way more of a closer connection to boats that the second that came home to a dirt home. The Admiral did put her foot down though and there was no way she was raising two kids on the boat, moved into a new home a month prior to arrival of #2.


SoCal is way more weather liveaboard friendly than Washington.. walking down the dock ..in the snow with a infant and all the associated stuff was a p.i.t.a.
HOLLYWOOD

I bet my wife would jump at the opportunity to buy you a drink and pick your brain about your experience (so would I). Did you ever consider adding a washer/dryer to your boat? My wife is a bit in love with the idea. Few boats have them built in, but we have been narrowing our search to boats that at least have the potential of adding one, like big closets or something like that (Probably a ventless washer/dryer all in one combo). We also considered using the engine room access door under the steps as a spot.
 
Been in San Diego for over twenty years and have never needed air but an electric blanket sure does the job in our "winters".
 
I bet my wife would jump at the opportunity to buy you a drink and pick your brain about your experience (so would I). Did you ever consider adding a washer/dryer to your boat? My wife is a bit in love with the idea. Few boats have them built in, but we have been narrowing our search to boats that at least have the potential of adding one, like big closets or something like that (Probably a ventless washer/dryer all in one combo). We also considered using the engine room access door under the steps as a spot.


There was no real place for a washer/dryer on the grand banks 36.. if there was I dont think cost would of got in the way. Boats are a bit of a dangerous place for a toddler with slick wood floors, sharp cabinet edges,steps to lower cabins, electrical goodies to play with ( when our girl could reach the electrical panel was the start of a frustrating period). But a bit of kid proofing made it a reasonable space.


We, and our daughter survived and it was a cool experience. The first time we anchored out and ran the zodiac to shore she screamed like a wailing banshee to the point a number of ladies standing on the dock were ready to call the cops because they thought she was being abused!. By the time she was 4 all she wanted was to go to the boat.



She was able to dock our next boat (50' full disp. single engine, 60,000 lb passage maker) by the time she was 11, it always freaked the old guard at the yacht club out to see this little girl barely able to see over the flybridge carefully piloting the boat into the harbor..



We "built in" a crib in the fwd. cabin that was screwed down and was very secure.. she typically slept whenever we were underway.


San Diego is a great place to live aboard.. awesome weather and a really cool boating community, a bit expensive .. but well worth it. I cannot think of a better place to live aboard and experience it with a child.



I found a old pic of her in her cabin standing in her crib.


HOLLYWOOD
 

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