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I would really like to use the T5's built in fresh air blower as part of my ventilation system. I don't think it would be the best idea to leave the van "on" overnight run off the main battery.

Does anyone know if its possible to break into the blower wiring at some point and switch its power source from the van, to a leisure battery? I was thinking about switching into the circuit before the 30A fuse. In other words add a switch that disconnects the hot side of the fuse from the vehicle battery and puts it on the leisure battery. This would mean I would still use the speed control.

The question is whether this would back power any other circuits in the van and cause a problem. It looks like it would power the "Auxiliary coolant heater relay" and I don't know whether that would be a problem.

Any thoughts?
 

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I would not use the standad blower - it's a power hungry beast (does not have to be effecient when the engine is running) & noisey to boot.

Otherwise it's possible - once you have found the feed you would need to use a changeoer switch - "common" terminal to motor circuit - other terminals to normal feed & leisure battery feed.
 

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Did you have any success with this?
I've done some investigation work and found a wire going into the HVAC control panel which will power the air blower via the speed dial. I'm thinking of adding a relay which will cross over to the leisure battery when the ignition is off.
I'm also curious as to what else I might be powering by providing power to the hvac controls?
 

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LIke Brian says I'd check the current drain of the blower before doing too much, it uses big resistors to slow it down and alot of power is sunk into them, common problem for them to burn out - not an efficient use of power when the engines off.
 
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