Vaillant turbomax 282e - F28 fault

[PlumbSafe]

I have this Vaillant Breakdown come in today, was serviced by an engineer yesterday, all was fine before his visit, custard says he said he adjusted it because he thought the burner was noisy.

What it does is on DHW it takes a couple of attempts to ignite but it works fine when it does.

when you want heating it lights after a couple of attempts but seems to be really low, then it cuts out after a couple of seconds and goes to lockout with the fault code F28.

I noticed an old gas valve and box at the bottom of the airing cupboard, so this may have happened before.

Any Ideas.

 

[Billy Bob Bob]

sounds like gas pressures out

 

[PlumbSafe]

this is controlled by the pcb, right, so its either the ignition pressure has drifted low or the pcb is shot, as it does work on dhw.

 

[SafeGasInstall]

i think F28 is a code for not having gas , if he changed the stings he mast have under gas the appliance i would check gas pressure and do use your analyser to read the levels of CO/CO2 ratios

 

[PlumbSafe]

I will do SafeGasInstall, I have the manual now so should be a lot easier to find fault, I will post result once I get sent back, its a council contract and the turn around on parts is shocking, I ordered a new Gas Valve and PCB thinking it was either one, hopefully its just ignition rate. what a difference having the MI's is to just winging it.