Webasto AirTop Evo 40 - fumes in ducting

[bozlite]

What could be the cause of diesel fumes in the warm air circulated by my Webasto heater? I’ve checked all connections and they seem sound. The cold air is from outside the boat - could the air intake be picking up exhaust fumes? The exhaust and air intake are on the same side of the boat - about 3 metres apart - and the current (abnormal) wind direction would suggest this would be possible. Other than that, a cracked heat exchanger? The heater is only 3 years old, though. Any thoughts or similar experiences?

Thanks.

 

[jiris]

What could be the cause of diesel fumes in the warm air circulated by my Webasto heater? I’ve checked all connections and they seem sound. The cold air is from outside the boat - could the air intake be picking up exhaust fumes? The exhaust and air intake are on the same side of the boat - about 3 metres apart - and the current (abnormal) wind direction would suggest this would be possible. Other than that, a cracked heat exchanger? The heater is only 3 years old, though. Any thoughts or similar experiences?

Thanks.

I would definitely investigate the possibility of sucking the fumes from outside first. Some leak inside the heater is possible, but very unlikely.

 

[bozlite]

I would definitely investigate the possibility of sucking the fumes from outside first. Some leak inside the heater is possible, but very unlikely.

Thanks - that’s what I’m hoping. I’ll do one last check that everything’s nice and tight and wait for the wind to change!

 

[pcatterall]

I assume by 'air intake' you refer to combustion air and in that case the air drawn in is expunged as exhaust.
A gasket could be another option. Assuming you have a co2 alarm then can you position it around the area to try to identify the source?

 

[bozlite]

I assume by 'air intake' you refer to combustion air and in that case the air drawn in is expunged as exhaust.
A gasket could be another option. Assuming you have a co2 alarm then can you position it around the area to try to identify the source?

No - by air intake I meant the cold air intake (the air to be heated and circulated). Just trying to track down the most likely explanation for exhaust air getting into the circulating air. I’ve got a workshop manual somewhere, so I’ll have a look at gaskets, as you suggest.

 

[matthewriches]

I’ve got a Eber on mine and whilst moored up alongside a barge at work, the exhaust fumes between the narrow gap were coming into the engine room vents then into the inlet of the heater...... = yuk!

Turned the boat around and all ok.

How old is the heater?

 

[bozlite]

I’ve got a Eber on mine and whilst moored up alongside a barge at work, the exhaust fumes between the narrow gap were coming into the engine room vents then into the inlet of the heater...... = yuk!

Turned the boat around and all ok.

How old is the heater?

Right - so there is a chance that the heater is sucking in its own exhaust. I'll see how things are next weekend. The heater's only about three years old, so I wouldn't expect anything major to be wrong with it.