Webasto Diesel Heater

[BobHicks]

[ATTACH=JSON]{"alt":"Click image for larger version Name: 20190509_132531.jpg Views: 0 Size: 66.7 KB ID: 2850","data-align":"none","data-attachmentid":"515843","data-size":"full","title":"20190509_132531.jpg"}[/ATTACH]In my 3888 I have a electric ac heaters in the salon, master and second bedrooms. I also have a webasto diesel heater in the engine room with outlets in the same 3 areas. I find the diesel heater puts out too much heat. The salon outlet goes through the upholstery under the dinette table and as it is only about a foot or 2 away from the actual furnace in the engine room it comes out so hot the admiral has to move or burn her legs. I am concerned the leatherette will melt or worse burn. Consequently I only use the electrics so far. I am thinking of moving the outlet to where the intake for the furnace is. Could I convert the intake to an outlet and get the intake air from the engine room?

[Tiltrider1]

You can do this but you will have all kinds of other problems with the heater unless you leave a window or door open while running the heater. With out an open window or door, your cabin will become pressurized, slowing down the air flow, causing over temp issues. Not a good plan. Just relocate the duct and use silicone tubing.

[BobHicks]

Thanks Tiltrider1, I had not thought of that issue. That is why I asked for input. I will have to see where else I can relocate to.

[ksanders]

My Wallace furnaces also put out really hot air. I do not think it’s dangerous hot, like melting things, but it is uncomfortable if you put your foot right in front of it.

If you do not like the location, i’d move it, and just put a blank grill cover over the hole.

Tiltrider did have a good idea as well. If you open up the intake to your furnace temporarially you will be able to quickly tell of you have a return air obstruction happening.

[sharpx]

In my 3888 I have a electric ac heaters in the salon, master and second bedrooms. I also have a webasto diesel heater in the engine room with outlets in the same 3 areas. I find the diesel heater puts out too much heat. The salon outlet goes through the upholstery under the dinette table and as it is only about a foot or 2 away from the actual furnace in the engine room it comes out so hot the admiral has to move or burn her legs. I am concerned the leatherette will melt or worse burn. Consequently I only use the electrics so far. I am thinking of moving the outlet to where the intake for the furnace is. Could I convert the intake to an outlet and get the intake air from the engine room?

I know this is an old post but by any chance do you have any pictures of where/how your heater is installed - I want to install one in my boat and trying to get some ideas, thanks in advance.

[Bobhicks]

Just saw this. Yes I can take some pic's if I can't find any.

[sharpx]

Bob, I got it installed so no need - was more challenging than I thought, thanks for the offer though, appreciated.

[Centerline2]

for something like upholstery to melt or burn, it has the get to a much higher temp than you can touch, so i agree that melting/burning of the material is of little worry, but i agree that the leg burning issue should be remedied ....
installing a diffuser may be an option, which is just a box that will allow the flow of air to slow down and spread out before it exits from the vent cover, instead of the small outlet as shown, which has the air and resulting heat condensed into a small stream of air at a lot higher velocity than a diffuser would have....

which, a diffuser is almost exactly what your intake box/louvre is if used as an outlet instead of an intake.... but a diffuser will have a baffle in it so the air will be spread out to flow out gently, and not just blown out the tube against the louvre, which would create a hot spot similar to what you are experiencing now..

my CABIN air intake to my diesel heater comes from the engine room (actually ducted to near the passive engine room vent), which allows the interior of the boat to have constantly fresh heated air coming in, displacing any damp or stale air that may otherwise build up in the living space... which REALLY helps if its a blustery day, as it keeps the widows free from condensate and fogging, and when a person comes in from outside, the constant allows ones clothes to dry out without creating a sauna....

the downside is that any odors that get created in the engine room could be blown into the cabin.... this could be bad if they are harmful gasses. or it could be good as it may allow you to know whats happening in the engine room when underway, as you would quickly notice an overheat problem....

I did this to insure reasonably clean air without having to build an intake box.... as for any CO gasses that one may worry about getting into the heating air, its my opinion that if the engine isnt running, there will be no CO gas to worry about, and if the engine IS running, the intake of the engine will use so much air that CO emissions could never build up, as it will be sucking more fresh air INTO the engine room vents than the engine will ever be able to produce into the area, keeping it safe..... and the engine bay in my boat doesnt have funky smells, so it works for me

the combustion air intake for the heater comes from the cockpit, which i have protected from any spray or flooding from a washdown hose... as for the CABIN AIR intake, sometimes we cook fish or crab in the cockpit, and of course in the process of catching the fish/crabs, we deal with baits and such, I didnt want the heater to blow any of the smells that may be associated with cooking crab, fish, old bait, stale seaweed or any other objectional smells that could cause unpleasantries into the comfort of the cabin.....

[SteveK]

I have a webasto with inlet under one settee and one heat outlet at the other end (2nd outlet at base of steps facing down hall). The setup has a house type thermostat in addition to a dial which came with unit so it turns off at set temp, whereas the dial is meant to keep it always running at variable fuel burn. This past week onboard got to test it.
Yes on the hot leg at a 3/4+ setting but not at the 1/2 dial setting. It also has directional fins I used to point the main flow across & away.
It sounds like yours are not using a lower burn rate and are either off or on full.