Hi,

I have a vaillant 837E turbomax and from time to time the water will not heat on opening of a tap. When the system is reset via on/off it reverts back ok. However the other day I got an F22 code(dry fire protection) and again it went back ok when reset. I have tried bleeding all the rads, fine, the pump is blead and turning freely and the auto air valve is slightly open as expected to auto blead air from system. All valves are fully open and mains is too. I have thought about the divertor valve, but why if it resets ok?? Also thought about flow regulator as the hot water can sometimes go hot and cold on its own and when the draw from the tap is reduced it goes hot again. This leads me on to thinking of checking the cold water inlet filter to see if there is any restriction but don't know where it is, as this may be affecting the flow. Any clues to the filter location and problem generally???

Many thanks,

Graham Adamson

graham adamson, March 2008

Hi,

One thing I want to check is the cold water inlet filter. DO you know where it is??

Graham.

graham adamson, March 2008

hi,

Haven't ever seen the double triangle in the display so no is the answer, however the lock out is very rare and not really the problem. It is more the production of hot water stopping. As it is intermitent it suggests a sticking valve maybe?? not sure but something I have been noticing is the lack of the warm start indicator green light comming on when hot water is demanded. Is this significant??

Thanks,

Graham

graham adamson, March 2008

one problem I have known with the turbomax is the air pressure switch, this does cause intermittent faults with this boiler, when it locks out does the double triangle flash?

gary.wright53@googlemail.com, March 2008

Hi,

The pressure is fine within the boiler, it does creep up but yes the gauge rises when topped up and when the pump is running.

Thanks

graham adamson, March 2008

is the pressure ok in the boiler?
if you try to top it up a bit does the gauge rise?
I have known the pressure gauges to block so it looks like the pressure is ok but it is not
does the needle move when the pump runs?

gary.wright53@googlemail.com, March 2008