Hot water fault

[hammers4spanner]

Meant to ask about this yesterday , friend of mine has a property where the hot water has suddenly stopped working .
Its an s plan with glow worm heat only boiler heating side works fine on demand for hot water pump spins ,two port opens but boiler does not fire . He has always used cylinder stat to call for demand and has no other control over hot water .seems to be 240v everywhere it should be bout can't think of anything i'm missing?

 

[Geyser]

Micro switch in zone valve not contacting to call for hot water.

 

[hammers4spanner]

Micro switch in zone valve not contacting to call for hot water.

it's brand new

 

[Geyser]

it's brand new

Is the head new or whole valve? Old valve body won't always move enough to let micro switch make. What make valve?

 

[hammers4spanner]

honeywell , whole valve changed two weeks ago then they thought it had gone faulty so changed the head other day.
All wired correct everything works other than boiler won't flash up on hot water call

 

[jonnyswamp]

Edited
Maybe too much info for open forum

 

[jtsplumbing]

When you say he uses cyl stat when he wants hot water ! has he not got a time control/programmer that he uses ??

 

[hammers4spanner]

no only a roomstat

 

[jtsplumbing]

Think system could do with a re-wire, have you replaced the cyl stat ?

 

[hammers4spanner]

Its just been rewired , had new pump head put on ,and new actuator , was working fine then just decided not to work on hot water .

Had a nosey myself can't see anything wrong other than it just won't fire on hw ,

I have thought about cyl stat however phoned up manufacturer and they reckon its working .

Not sure if you can link it out tho

 

[ShaunCorbs]

Its just been rewired , had new pump head put on ,and new actuator , was working fine then just decided not to work on hot water .

Had a nosey myself can't see anything wrong other than it just won't fire on hw ,

I have thought about cyl stat however phoned up manufacturer and they reckon its working .

Not sure if you can link it out tho

link the cy stat out to see if not i would say wiring