Webasto install location

[Thor5000]

Planning to install a Webasto Air Top 55 in my 1982 Marine Trader Double cabin 34. I was wondering where other installers had chosen to mount the unit and run duct work to the two cabins and salon. Any recommendations or tips are greatly appreciated. Thanks in advance.

 

[Scooby5959]

Pretty much wherever you would like .I installed mine underneath or in the seating area with a short hose into the main cabin pretty much anywhere ,use a small fuel tank not far from the unit, Run on kerosene .Look at the Chinese knock off unit for a fraction of the cost they’re supposed to work just as well so you can put one in the main cabin and one someplace else of course you’ll need a fitting to exhaust to the outside of the boat 50 60 bucks for that .I don’t like them in the bilge or the engine compartment much easier to get to inside a cabinet in your house

 

[Bmarler]

most, if not all, forced air heaters will have a maximum distance to first air outlet. sometimes this is a short as 5 feet. that's not to say that it won't still put out heat if your duct is longer than that, but there could be warranty issues.
that distance is about easing the back pressure in the duct so the heater can push the heat away from itself. it will reduce the lifespan of the heater if you don't duct it properly.
that said, i have an espar d4 with double the distance to first outlet. as a liveaboard i got about two years before the combustion blower needed replacing. i just kept a spare on-hand so i didn't have to wait for delivery. they never fail if it's not freezing outside.

 

[AKDoug]

I mounted mine under the counter in the kitchen, under and behind the sink using the curve of the hull for my clearances. The installed a partition between the storage area and the heater so nothing could come into contact with anything hot if things might move around in heavy seas.

It was conveniently close to duct in fresh outside air so I heat cold air to make hot air, which lowers the moisture content of the freshly heated air and helps keep the cabin drier. You wind up with a slightly higher cabin air pressure when it runs vs pulling intake air from inside the cabin.

Ducting exhausts from under the stove into the main cabin, and Y's off running forward under the gunnel to the forward cabin, exhausting from a closet across from the bathroom with a direct able vent so I can heat the bathroom or the berth area. Another Y splits off to direct air across the windshield through a smaller direct able vent.

I hope this helps give you some ideas!

 

[C lectric]

most, if not all, forced air heaters will have a maximum distance to first air outlet. sometimes this is a short as 5 feet. that's not to say that it won't still put out heat if your duct is longer than that, but there could be warranty issues.
that distance is about easing the back pressure in the duct so the heater can push the heat away from itself. it will reduce the lifespan of the heater if you don't duct it properly.
that said, i have an espar d4 with double the distance to first outlet. as a liveaboard i got about two years before the combustion blower needed replacing. i just kept a spare on-hand so i didn't have to wait for delivery. they never fail if it's not freezing outside.

About backpressure on the first outlet.. A larger hose and vent outlet than suggested will have a big effect on the back pressure the furnace sees.
I am talking generally since I don't have a furnace. But I have dealt with some of that in other areas when I used to work.

 

[Bmarler]

About backpressure on the first outlet.. A larger hose and vent outlet than suggested will have a big effect on the back pressure the furnace sees.
I am talking generally since I don't have a furnace. But I have dealt with some of that in other areas when I used to work.

totally agree with that. i like to run the bigger size ducting, (100mm). both inlet and outlet. but some folks don't like drilling so many huge holes in their boats.
after the first outlet the distance can be much longer, and you can play with the duct size a bit, but when you get out too far the air velocity decreases quite a bit. with these smaller heaters i don't usually install more than 2 outlets.

 

[AKDoug]

I am running an Airtop 3900, and with the louvered vents I can close the ones in the areas I am not in to enhance heating in other areas, or to reduce the flow into those areas.

 

[Bmarler]

I am running an Airtop 3900, and with the louvered vents I can close the ones in the areas I am not in to enhance heating in other areas, or to reduce the flow into those areas.

i do that with the espar d4 also. your 3900 has a much higher heat output though, so probably better suited for more outlets.
espar claims up to four outlets, but i'd have to disagree.

 

[dcolman]

Diesel heater enclosure

youtube "diesel heater in pelican case"
external bulkhead mount removes any worries about carbon monoxide.

 

[Nomad Willy]

I’ve had one side and one stern.

Didn’t really make much (or any) difference.
Side best to port w counter rotating prop. Heat could cause damage to fenders ect. with side exhaust.
If you’re the type that socializes on the aft cockpit in port stern would be too noisy.

 

[Lepke]

If you want a semi-portable heater, you can buy the heater and fuel tank in a metal case, ebay or Amazon.

 

[Slowmo]

Our Espar is mounted to the forward bulkhead in the engine room. It then has a short duct up under the salon settee. Longer ducts run to the aft cabin, fore cabin, and both heads. Having it the engine room minimizes noise and provide direct access to the fuel source.

 

[Bmarler]

If you want a semi-portable heater, you can buy the heater and fuel tank in a metal case, ebay or Amazon.

it's crazy how cheap those are to purchase. i could buy two or three of them for the price of a single air handler on my hydronic system.