Webasto heater does not shut off

[Familyguy]

When using the heater I have noticed that when it gets up to the set point and ‘shuts down’ the fuel stops pumping and fan continues through cool down but after it is cooled down the fan will slow down considerably but never actually shut off. This is fine while at the dock but on the hook it will definitely drain my batteries. Question: Is the fan running all the time ‘normal’?
Thanks, in advance, for your replies.
Jim

 

[NorthernFocus]

Yes that is normal. The temperature sensor is in the inlet air duct. There must be some air flow to monitor cabin temperature for the thermostat to work. It is extremely low amperage so not a practical issue for battery drain.

 

[BradOwens]

In warm weather, you can turn the unit off completely by pushing the button on the control panel. That will turn off the fan and save your batteries.

 

[Familyguy]

Thanks for your input! Love this forum...
Jim

 

[Rocky Lou]

The temperature sensor is in the inlet air duct.

I find there is a huge difference, more than 10 degrees F, between the actual ambient temp. measured by a very accurate thermometer and the ambient reading on both of my Webasto control units. In some cases, it says 59, when it's really 72. I pulled the input grills and don't see the actual sensors, so it looks like a major investigation to actually get to them and check the temp at their location for comparison.

 

[johnbenj]

Where is the inlet air duct on a 27OB?

Sent from my SM-G975U using Tapatalk

 

[Mike and Sarah]

The webasto heater is under the helm seat. Remove the microwave and you will see it back in there a ways. It just pulls air from under the seat from what I can tell. Air comes in around the seat and starboard side panel under the Yamaha control. There is no inlet air duct just a outlet duct that runs from the heater to the the helm and vberth vents.

 

[MarcoArias]

As the others have commented above, this is normal.

The Webasto unit has an internal temperature sensor that monitors the ambient temperature via the inlet air supply. To do this accurately, the fan will slowly bring air into the unit. As the temperature falls and rises, the system will react accordingly with regards to the setpoint temperature.

Happy Boating!