# Frost protection valve in Hymer B534



## ceremita (Sep 10, 2007)

Our much loved Hymer B534 has a Trumatic C3400/C6000 heating system There appears to be an odd problem with the frost protection valve, in that it will not reset itself and therefore water continuously drains out. Have read several threads re this and understand about using a clothes peg or similar to wedge it in closed position, but ours will only close when slight pressure applied to yellow button to hold it down! Cannot find anyone who could supply a replacement valve. Does anyone know how I could replace the valve with a manual one and what valve should I buy and where from? 
:roll:


----------



## pieterv (Feb 3, 2009)

Before going down the replacement route make sure the valve gets its 12V supply. When the 12V is switched off centrally the valve will open and drain the boiler.

(Normally, the 12V on/off switch will not switch off the 12V to the valve, but on my Hymer the switch on the Elektroblock will).

So, might be worth checking it's fuse, and taking a multimeter to the wiring supplying the valve.

If you do want to go down the route of adding a manual valve, then I would think there is no reason to remove the current on as it is open anyway. Just find a manual one that fits the hose coming out of the valve, i.e. any water valve with the right diameter connections should do.


----------



## Brock (Jun 14, 2005)

Sorry if I am stating the obvious but have you tried Truma? I presume you are following the instruction manual - you can download these from Truma - and are not trying to reset the switch when the temperature inside the van is below 10C. Have you drained the van for winter and forgotten to do something to ready it for the summer? I drained the van once and forgot to close the valves so water gushed everywhere when I refilled.


----------



## eribiste (May 1, 2005)

The last time I had to re-set my frost valve, it wouldn't re-set until I started the boiler system. I started the heater off (on the blown air heating seting), re-set the dump valve, then opened the taps to bleed the water through. Been right as ninepence ever since.


----------

