Might be having a problem with my webasto... and it's getting cold.

Enabled the webasto and turned up the thermostats. Fans at vents are blowing. Air is cold. Webasto is NOT firing. Sound at webasto is a bit high pitched... strained.

So to see if it will fire, I hit block heat. (Do all coaches have webasto set up to heat block?) Now it fires up, and well at that. No smoke, just a clean, hot burn. Water temp rises quickly. AND, the living room starts heating up. Ahhh, as I understand it, with the block heat button pushed, it opens up a circuit that allows the heat from the engine to be used to heat the living areas... and domestic hot water as well.

Turned block heat off. Living areas got cold again. Turned on webasto to heat domestic water, fires right up. But this time, it doesn't heat the living area. Only when the block heat button is pushed.

Is it possible that the valve that allows the webasto to heat the living areas is stuck shut? And then the "heat" only gets to the living areas when the block heat circuit is open?

About to go to Montana. Do I need a part? Yikes, it's going to be cold up there.

Thanks for any advice. It's late and cold:-)

Adam