No hot water on my unvented cylinder

[Harveynig]

Hi when I turn on my hot water at the programmer the pump kicks in but nothing happens at the boiler. I can only heat the water when the heating is on. I've looked at the two port valves and they are not working so I have took of the motorised head and manually opened the valves still the boiler doesn't kick in when I call for hot water it's al most like the wiring or some thing has been done wrong cant get my head round it just wondering what it could be ???​

 

[nysk2008]

does the heating work?

 

[Millsy 82]

Has it worked before hand? if so it wont be the wiring. check the 2 port with a multimeter if its not motoring across then it wont call for the boiler

 

[Harveynig]

By all accounts it always been like this. Yes the heating works when I call for heating. Both mortised valves don't work in the sense of turning the valve on and off

 

[diamondgas]

Pump and boiler or usually on the same switched live 's'or'y'plan ... If your pump is on then I'd be expecting the boiler to fire also. Are you positive the pump is running? And if so can you hear anything at the boiler? What boiler do you have fitted, make and model, also what UV cylinder as some have system wiring attached? A bit more info will reduce the possibilities to be honest

 

[Megaflo-Experts]

It sounds like your hot water 2 port valve is not opening enough to trip the micro-switch, which in turn sends power to the pump/boiler.
Manually opening the valve will not open it enough to engage the micro-switch.

By setting the programmer for hot water AND heating, suggests that the valves are opening and the call for heat from the heating side is firing up the boiler and pump.

The only contradictory statement is when you say, the pump kicks in when the programmer is set for hot water. I assume this is for hot water only, and not both heating and hot water.
Also, are you 100% sure the pump kicks in when set for hot water only?

 

[Harveynig]

It sounds like your hot water 2 port valve is not opening enough to trip the micro-switch, which in turn sends power to the pump/boiler.
Manually opening the valve will not open it enough to engage the micro-switch.

By setting the programmer for hot water AND heating, suggests that the valves are opening and the call for heat from the heating side is firing up the boiler and pump.

The only contradictory statement is when you say, the pump kicks in when the programmer is set for hot water. I assume this is for hot water only, and not both heating and hot water.
Also, are you 100% sure the pump kicks in when set for hot water only?

Yes I'm sure it kick in when only calling for hot water. That's what is confusing me.

 

[Harveynig]

Pump and boiler or usually on the same switched live 's'or'y'plan ... If your pump is on then I'd be expecting the boiler to fire also. Are you positive the pump is running? And if so can you hear anything at the boiler? What boiler do you have fitted, make and model, also what UV cylinder as some have system wiring attached? A bit more info will reduce the possibilities to be honest

The boiler is a potterton suprima 50 UV cylinder is a ariston comfort indirect it's a s-plan. I'm sure the pump runs when calling for hot water and there is nothing from the boiler

 

[Mike Jackson]

Time to call someone in to look at it in my opinion. If you don't know anyone local try posting in the looking for a plumber section.

[DLMURL="http://www.ukplumbersforums.co.uk/im-looking-plumber-gas-engineer/"]I'm looking for a Plumber or Gas engineer.[/DLMURL]

 

[diamondgas]

The boiler is a potterton suprima 50 UV cylinder is a ariston comfort indirect it's a s-plan. I'm sure the pump runs when calling for hot water and there is nothing from the boiler

The pump should be wired from the boiler on a suprima far as i remember. the suprima also has a time delay... AND both should come on!

I agree with Mike, time to get someone in ... I'd be edging towards the zone valve but would want to check wiring first

 

[Harveynig]

Could it have anything to do with the wiring from the cylinder thermostat ?

 

[mountainman]

Why specifically the cylinder 'stat?

 

[Harveynig]

Why specifically the cylinder 'stat?

Just thought that the stat could be faulty so that's why the boiler doesn't fire up to heat the cylinder

 

[mountainman]

It could be a number of things and just guessing is getting you nowhere.
Would it be insulting if I suggested you employ someone who knows what they are doing to sort your problem out?