Potterton Suprima Boiler is not working, can anyone help pls

Potterton Suprima Boiler is not working, can anyone help please?
The CH and HW were working together well but when just HW switched on, the boiler made some terrible noises (go bang) then red light got on and stopped to work, after a few times resetting it start to work again without problem. Then a Corgi reg Plumber changed the Pump and 3 Valve and charged me £ 498 and gave me one year guarantee. After 6 hrs HW stopped to work totally. I informed to Corgi reg plumber, they sent different guy, and he couldn’t understand the problem then after one week they sent again another guy, who didn’t come to look at the boiler, in front of the house told me that the boiler need be changed to combi boiler which will cost me around £2000. At the moment the CH is working perfectly but when I switch on the HW, the red temperature light gets on, and boiler stop to work.
The boiler fitted in the kitchen (First floor), cylinder is in the second floor and tank is in the loft. The cylinder working with electricity option from the second floor for HW, but HW with boiler is not working. British Gas was informed and after free checking, they told me they want to change whole system and it will cost me around £ 3000. The house and boiler are 12 yrs old. I am looking for any professional and proper advices please?

PCB.....................

Call heateam 08706 096096, Pottertons own engineers, for a fixed price repair

gotta be more than that... even bg would've launched a board at it.

what does the flame picture do when hot water only selected? does it jump? id defo get the company back to sort it who charged u in my own opinion an extortionate amount of money. and they haven't even sorted the job.. was the system bleed correctly too? but i think baxi pot is on the correct lines with the pcb.

OP what did bg say the problem was... for £3000 they would not be changing the system... was this advice they gave in terms of upgrading an out of date system or something else?

bellairaphon said:

what does the flame picture do when hot water only selected? does it jump? id defo get the company back to sort it who charged u in my own opinion an extortionate amount of money. and they haven't even sorted the job.. was the system bleed correctly too? but i think baxi pot is on the correct lines with the pcb.

Click to expand...

Hang on, the PCB does not know what the boiler is supplying heat to!

That firm were possibly on the right lines but may have wired up the three way valve wrongly or the fauly may have been a blockage in the HW circuit.

Whatever, you have paid them over twice what we would have charged, so call them back!

Tony

Hmmm... If the boiler locked out on both CH and DHW, then I would agree that the PCB is a possibillity.... I would first look at the water circulation and make sure that flow is adequate, no airlocks.. But if this was OK would look closer at the PCB/ temperature control.

Think I'm gonna have to revise my pricing again as I'm still far too cheap

but didnt the op say it did work for a short period of time. i didnt say it was the pcb but could be an intermitent fault and the pcb could be the reason. im not a pcb guy when i was training it was think pcb and think again. I do hope he gets the company back to sort it. they have better eyes on then any of us.