Intermitent HW, CH is ok ?

[ctaylor]

I have been having problems with the hot water, it was ok and is now playing silly beggers. It stopped altogether and the only thing I touched is the 3 port valve (Honeywell 400003916-003) with the bobble ontop.
It then worked for a week and has now stopped.

It seems to have a manual position and an Auto position but not entirly sure where it should be and if it is the likely culprit. From what I have read it is possible on this model to by the Replacement Powerhead (metal box part) without having to drain down

Any advice would be appreciated. CH seems to be ok although I noticed the rads are still hot when I turned the CH off at the programmer.

Thanks

 

[seco services]

if you select hw only is the boiler not firing up ?

the hw don't really have no connection with the 3 port as such.
the sw/live comes straight from the cylinder stat not through the valve as the ch sw/l does.

 

[Hugh Jaleak]

Should normally be set at auto. Manual 'wedges' the valve open when filling the system.

 

[ctaylor]

Thanks Hugh,

I noticed that the motors for these Honeywell untis are replaceable and available for a tenner online, any ideas if its likley to be this or not.

We found last night that the water and heating were on together but the rads stayed on even when the room thermostat was turned down.