Demisters

[Salty Sealine]

Sealine F33. Previous owner told me the demisters only work when the heating is on, so tonight I turned the heating on and still nothing. Very hard to steer the boat with the screen all fogged up.

Any suggestions welcome as to how get the demisters to work.

 

[Hurricane]

Our old Sealine T51 had demisters.

The system was a heat exchanger on the port engine cooling system that heated cabin air ducted to vents under the windscreen. A fan in the duct was the only form of control.

So, if the engine was running the demist air was hot and the only way to turn it off was not to run the fan.
Consequently, if the engine wasn't running, the demist air would only be at room temp - with the fan running.

Basically - its hot air or nothing!! And only when under way.

The hot water heat exchanger was ubnder the stairs in the companion way to the lower deck. It was on the same pipework as the primaries to the domestic hot water.

Don't know if this helps - it might be similar for the F33

 

[aquapower]

Some demisters work off central heating through a diverter, you have to pull out the lever first (bit like choke) as usually you have heating only or demister only, not both together, lever is often near the helm.

 

[mikesyam]

My 2002 F33 factory fitted demisters work off the heating, if you lift the floor in the saloon you will see the Eber heater port side and a large pipe comes off it running across to the starboard side which splits 2 ways with a T piece, one goes to the vent in the saloon and the other runs forward to the demister, if you look just after this T piece you should see the fan/blower motor which is controlled by the switch on the panel at the helm. if you run it without the heating on it blows cold air and with the heating on its obviously hot, they dont work that well mind and mine appears only to blow out at the helm and mine also mists up badly, have to open a window to help keep it clear.

 

[mjf]

On my princess the de-misters work by blowing air through a labyrinth of pipes from the domestic HW system. Works well but must have HW for warm air obviously either via immersion heater (leaving berth) or port engine when underway