Radiators not heating up

[cbrand]

There is no wall thermostat, if i leave the hot water on continuously yes the hot water is hot. It seems like the boiler is heating up water for the heating it just does not seem like it is going to the radiators.
For example, if I put the hot water tap on very hot water water comes out, once the amount of water in the boiler/pump empties then the boiler flame ignites and less hotter hot water goes out of the hot water tap, if that makes any sense as i have hot hot water on the coldest setting?
The system pressure is 1.5 with the heating off, i had it on at 1 bar but it made no difference. When the heating is on, it goes to 1.7

 

[terryplumb]

Does your boiler have an integral timer ( clock ) ? When you drained down ,did you turn the selector switch ( far left hand side ) to off ( 12 oclock position ) ?
If your answers to both the above is YES ,then the timer has to be reset .

At any time did the red flame failure neon alight ?
How old is the boiler ?

 

[cbrand]

nope i did not touch clock, i have set the heating to continuous and not timer mode. No the red flame failure light did not come on at all at any time.

 

[cbrand]

Not sure how old the boiler is more than 8 years. Recently had a new pump and prv fitted

 

[terryplumb]

Does your boiler have an integral timer ( clock ) ? When you drained down ,did you turn the selector switch ( far left hand side ) to off ( 12 oclock position ) ?
If your answers to both the above is YES ,then the timer has to be reset .

You have not answered the question ,regarding when you drained down. If you turned function selector to off ,the timer HAS to be reset.

 

[cbrand]

I have reset the boiler but it is not making a difference it seems

 

[terryplumb]

Please refer to the boiler booklet / manual on how to set the integral timer.
I have asked you twice if you turned the function selector to the off position when you drained down ,and you gave no answer. I will state again ,if you did you MUST RESET the timer.

 

[cbrand]

I did turn off the boiler yes when I drained the system. There is no other reset option in the manual other than turning the dial to R (installation & servicing manual).
Thank you

 

[terryplumb]

Turn the timer dial ,till the actual time is lined up with the little arrow. All around the dial are little segments that can be pushed in ,or pulled outward. Pull ALL of them out. The little switch ,flip to timed . observe the boiler ,the neon lights , and advise if the boiler fires up ( burner on ,orange neon alight )

 

[cbrand]

The timer works fine, if I set it to timed (as you mentioned above) or continuous the boiler fires up, the pump comes on & the pressure rises, including the flame light (orange neon) for a bit then the orange/flame light goes off. The pump keep spinning and gets very hot.
If I move/set the timer to 0 position (off) the pump goes off, so timer seems to be working fine.

 

[terryplumb]

Ok , so boiler is firing on demand ,but the heat it generates is not being disbursed thru the c/ heating. I assume you did not close any isolation valves on the boiler flow or return pipes when draining down ,so the pump may not be spinning or its full of air ,or the diverter valve is stuck in dhw position. If its the latter you will need an engineer.

 

[cbrand]

i have vented the pump and bleed the radiators

 

[cbrand]

Also I changed the diaphragm for the CH differential valve about a month ago

 

[terryplumb]

Engineer time then. British gas will do a one off repair ,even if you dont have a contract with them ,or buy gas from them. Its around ,90 quid including parts if the repair can be done in half hour ,but goes upto ,200 if upto two hours.

 

[cbrand]

Thanks, whats the cost after/over two hours?