Vaillant Turbomax Plus - "S33" code.... Again!!

[Moibr]

Help, Im getting the S33 code again despite changing the air pressure switch twice.

I have been getting an S33 code on my 5 year old Vaillant Turbomax Plus, I had the air pressure switch replaced and it worked perfectly for 6-months then it went again, same code "S33". So I called out the engineer again and he said it could be the switch again, so he replaced it, and the boiler still doesn't work- he then said it could be blockage in the flue, so he cleaned that and still not working (same code "S33").

He then removed the boiler's outside casing, it workes perfectly without the casing, but when he put the casing back on - it doesn't work!!

I wonder if someone might know what the problem could be. I have contacted Vaillant, but they are not very helpful.

 

[corgigazza]

The venturi on the fan assembley may be partially blocked or the flue may be blocked or disloged internally corgi job only

 

[Moibr]

If the Venturi was blocked would the boiler still work when the case is removed?

 

[Agile]

Yes of course!

Thats partly how we know what has caused your fault!

It seems you need a competent CORGI engineer. Yours may or may not be registered but he certainly does not sound very competent!

Tony

 

[bogstandard]

GEt someone competent it would appear that your present "expert" is anything but!!!
Oh Good luck