Any Potterton experts out there ...

[Riley]

I really never come across these boilers in my neck of the woods so I'm at a bit of a loss with this one. Potterton Performa 28. Frustrating intermittent fault, boiler was losing pressure but I recharged expansion vessel and that seemed to stop it until the past couple of days. Every other day now The owner is having to reset the boiler as it has locked out 30°c / flame fail neon flashing when he resets it,it works absolutely fine. He is looking to sell or rent the property so needs to get it remedied. It has never faulted when I've been There so cannot fathom what part of the process isn't working. Does anybody have any experience of these

 

[Riley]

Anyone?

 

[hammers4spanner]

All the usuals like pressures ok?

Flame rec?

 

[SmokeyJ]

Check the burner and injectors are clear. Had a few where it has ignited but a burner rail or 2 on flame rec side hasn't lit or has a weak flame. Just keep an eye on the left through the site glass when it ignites/low fire and see if any difference in flame height near the flame rec probe.
Check minimum/ignition burner pressure usually 2mbar(ish) - pull off one of the modulator wires on gas valve to check.
Apart from that as previously said the usual checks.
Good luck

 

[Riley]

I've done all the basics and I'm assuming that it must be a fault that occurs when the boilers been running for a while as it's never locked out while I've been there b

 

[Billy Bob Bob]

if the obvious checks rule out ok it comes back to the pcb,one thing worth trying that i have seen a few times,open hot tap,leave it get hot,turn the tap down low,if it kettles pcb is not telling the gv to modulate down,it will eventually lock out,also remove the venturie,they can oval ever so slightly,normally caused by the fan relay in the pcb

 

[oily face]

I'm no expert but check the gap between the electrodes the re should be a 4 mm gap but over the years of use this can change causing flame failure

 

[Elgordo]

Check the min pressure at gas valve ,if it's set too low the boiler will lock out when it modulates down when up to temperature