locating diesel heater in engine room

[lumphammer]

I am thinking of installing a new diesel hot air heater in the engine compartment bolted to the rear bulkhead. Thinking through the process I realised that this will be about 500mm above the three maintenance free batteries, and I'm wondering if this could be a problem if the batteries are giving off hydrogen as they are being charged.

Am I right to be worried or should I think of a new location?

 

[nimbusgb]

The flame part of a diesel heater is 'outside' the boat. Provided there is no electric fault it should be fine.

That having been said i'd also think about it!

 

[Ian_Edwards]

I think you'd have to pipe the combustion air supply from outside the boat and the hot air supply from outside the engine room.

At the very least you have to make sure that both the heater and the engine had an adequate air supply and I don't think you'd want to circulate engine room smells around the boat.

The heater may also too hot to operate correctly whilst the engine is running.

 

[Storyline]

Sorry to jump into your thread but I have a similar question. The ideal location for our diesel heater would be in the cavern and the gas locker is also in there. Is the flame from these heaters completely contained within the burner/heat exchange unit ?

 

[pvb]

Sorry to jump into your thread but I have a similar question. The ideal location for our diesel heater would be in the cavern and the gas locker is also in there. Is the flame from these heaters completely contained within the burner/heat exchange unit ?

Yes.

 

[pvb]

I am thinking of installing a new diesel hot air heater in the engine compartment bolted to the rear bulkhead. Thinking through the process I realised that this will be about 500mm above the three maintenance free batteries, and I'm wondering if this could be a problem if the batteries are giving off hydrogen as they are being charged.

Am I right to be worried or should I think of a new location?

I wouldn't worry about it at all. If I were minded to be worried, I think I'd be more concerned about sparks from the starter motor.

 

[Trident]

The burner of these units is completely enclosed and vents through the exhaust outside - the exhaust pipe itself gets very hot but can be wrapped in insulation - its worth bringing the fresh supply from outside through a vent to make sure you get dry fresh air in to the boat though. I just had a full wet system installed (Webasto) by a professional Webasto dealer and they put mine in the engine bay so it clearly isn't something they think is a problem.

 

[Storyline]

So the op and me should be OK with our locations (without any liability!).

 

[sailorman]

So the op and me should be OK with our locations (without any liability!).

Would you like it in writing & signed :ambivalence:

My boat has a large lazerette ( filled up with steering quadrant autohelm ram.gas locker) in the retouse transom all open to the engine bay.My heater is abaft the engine & accessible via the transom

 

[Storyline]

Would you like it in writing & signed :ambivalence:

If you are wrong, a piece a paper will mean nothing

 

[cryan]

It is not an ideal site. I carried out a small repair on a diesel heater where the problem was a very simply short at the ignitor connection. Caused by corrosion and easily fixed with new terminals and some heat shrink. However had that fault occurred in an atmosphere full of either LPG or Hydrogen from batteries I would think there would have been a risk of that small fault being somewhat more spectacular (explosively.)

 

[David2452]

Right way to install in engine room, assuming forced air not coolant based:
Above batteries install needs to be taken with care and you need to be mindful of the BSI regs for ultra low voltage installations as far as the cabling goes, or at least I do. The exhaust if lagged with proper insulation tube will not be an issue at that distance, I can actually hold it close to the exhaust port if so done. Under no circumstances should the recirculated air be drawn from the engine room, combustion air may be drawn from there with the proper intake tube, LPG lockers should not be an ussue as they will have no connection to the engine room or any electrics and should be entirely separate with an overboard drain. The foregoing assumes a diesel engine and under no circumstances applies to petrol powered craft. Done like that I do give a piece of paper, and yes it does mean something for insurance and BSS purposes.

Edit to say the above applies to marine spec heaters only not second hand or even new come to that vehicle units with internal temperature sensing.