vaillant, failed today!

[REDSAW]

turbomax plus 834, fires up for a min or so then goes off then cycles again. pressures 1.5bar.
f22 on index fault.
there is no heat transfer on any pipes below or inside boiler from p-hex apart from h-ex f&r pipe! pump and fan running!!!!!!!
help
gone home:disappointed:

 

[GrahamM]

Pump or divertor Knackered or blockage. Sometimes faulty thermistors give F22.

 

[REDSAW]

Pump or divertor Knackered or blockage. Sometimes faulty thermistors give F22.

it says dry fire!
there was a small weep above the therm on the high stat that was dripping on it but i sorted that and dried it!
my initial thought was the motor pin on the div-valve but thought it will be open to heat or hw though?
cant understand why its not pushing anywhere down pipes unless its blocked solid!

ta

 

[Roger Welton]

was it going around the plate?

 

[Billy Bob Bob]

What resistance are you getting on the primary(CH) Thermistor

 

[REDSAW]

was it going around the plate?

yes, getting hot but not out!

 

[REDSAW]

What resistance are you getting on the primary(CH) Thermistor

15ohms

 

[Billy Bob Bob]

15ohms

Back to what Graham said ,is the pump working?

 

[mfgs]

Pump or divertor Knackered or blockage. Sometimes faulty thermistors give F22.

Agree with this. Sounds like you've ruled out the thermistor if 15k ohms at room temp? Look at the pump and diverter.

 

[Last Plumber]

Sounds like a blockage to me, check filter/strainer and pipework internally from primary heat ex as well as what above have said