Vaillant turbomax fault finding f33 fault code

[The831Bunny]

Hi Tony

If the APS is not switched in a certain time frame with a demand (s) (not sure but 15 mins springs to mind) a F.33 is registered. Before this a status of S.33 is displayed if the i button is pressed. DM may know more than this, but I've never bothered to wait that long!

D.24, check the code as the fan comes on, if it goes 0-1-0-1 and ignition spark is intermittent, change the APS. In fact change all black APS's, its just a matter of time...

Now thinking about it the 637/837 displays f.33 not other 6xx/8xx Turbomax models. They just do S.33

Its late...

Bunny

 

[Agile]

Thats fine Bunny. So the fault is failure to operate the APS within a set time limit. I would have expected 1.5 minutes would have been more likely.

But where does antifreeze protection come into this?

"""f 33 Main heat exchanger anti freeze protection mode"""

Tony