Water not warm

[teejay246]

Fully pumped vented system with separate hot water circuit. HOT WATER ONLY setting: My boiler fires up OK first thing, but does not get the hot water up to the usual temperature. When I turned the boiler stat control, no clicks of the stat could be heard whether I turned it up or down. So I turned on the heating and still it didn't make the boiler fire again. So I fitted a new boiler stat on Saturday. Central Heating seems OK but the hot water is still not getting hot enough. Turn up the stat - no response. Let it all cool down and it responds.
I see it is connected via a terminal to which the gas valve is connected also. Could that be the problem. [/quote]

 

[Agile]

Its totally unclear to me what you are trying to describe! Telling us the make and model of boiler would be a good starting point!

You seem to have replaced a part without really knowing if it was at fault. Did you fit/wire it correctly? Where did you get the part?

Tony

 

[45yearsagasman]

What do YOU mean by fully pumped vented system. Describe other system controls, ie zone valves, cylinder stat etc.

 

[teejay246]

Boiler is an Ideal Mexico CF100. 18 rads, 2 zone valves. Stats on all rads.
1 week ago, called the pro. He was just leaving to go off on holiday - still away till August - but he said symptoms indicated boiler stat.( it was the original stat - since new ) i.e. system fired once then no repeat and unresponsive stat. We lived with it till saturday and lukewarm water so I bought the right part from plumb Centre. Straight forward to fit and, as I say, CH seems to work OK. But with stat setting on higher than we would normally have it - still HW not as "Hot" as it should be. and when I move stat to a higher setting, sometimes it clicks and the boiler fires, other times - no click, no fire. Had a new pump fitted last year. The HW circuit gets air in it (noisy pump sometimes) With the CH on - no noise. What more can I tell you? Thanks for suggestions. Only had to re-connect new stat as where old one was connected. Rest of the wiring is complex because of valves etc.

 

[45yearsagasman]

First of all, check the system is full. Check header tank in roof space and ensure all air is vented from system.
Drain some water from the system and check that the header tank is re filling, thus proving a clear cold feed pipe.

 

[teejay246]

OK Thanks. I'll give it a go.

 

[Agile]

Any competent engineer would be measuring the flow and return temperatures from your boiler to diagnose exactly what is happening with your system.

Tony

 

[45yearsagasman]

That would be AFTER checking the basics!!