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Andrew Smith
Andrew Smith, Plumber
Category: Plumbing
Satisfied Customers: 3756
Experience:  City and Guilds qualified plumber
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I have a Vaillant TurboMax Plus (I think it's an 824 or 828).

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I have a Vaillant TurboMax Plus (I think it’s an 824 or 828). It’s been turned on after over a year of not being used. When I turned it on a couple of days ago, it started up, the starting pressure was 1.2psi (mid green range), the burner came on (along with the yellow light) and after about 10-15 seconds it s uphut off and showed an error code F.22. I researched the F.22 (“dry fire”) and I bled the radiators (there was no air in the system), tried again, no good, so I increased the amount of water in the system and took the pressure up to 1.7psi and tried again. No good. I bled the system and took the pressure back down to 1.2psi. Still no good. F.22 every time, even after a power off and after a soft reset too. But no red light ever came on.
I noticed that if I power the boiler on with the hot water tap (which is full of cold water!!!) open and the water running, the F.22 doesn’t happen but everything else does. The unit will start up, the burner will light, the gauge display temperature will rapidly go up, then at around 50-60 degrees Celsius, the needle on the pressure gauage will swing back and forth rapidly with a lot of noise coming from the boiler, then suddenly the yellow burner light will turn off and the temperature gauge reading will drop very fast at first then more an more slowly. But the unit continues to sound like the burner is on.
Then as the temperature reading on the gauge drop to about 29 degrees, suddenly the electronic ignition kicks in and the burner comes on along with the yellow light. Then after a few seconds to no more than 10 seconds later suddenly the temperature gauge shoots up very quickly and the pressure swings up rapidly for a second and the gauge swings wildly again, the boiler makes a few clanging noises briefly and the yellow light goes out and it seems that the boiler stops heating. But no error code.
If I leave the boiler to just keep doing this, every several minutes the same things happens again. Any ideas?
***** ***** : It sounds likeyour pump is seized
***** ***** : Can you take the screw op
***** ***** : out of the centre and see if the insides are turning

Hello Andrew, I'm not sure yet how this website works, thanks for your answer and for your patience.


Your suggestion sounds very good. I'm having trouble though trying to get the large cover off the unit to be able to look inside.

***** ***** :

Usually a couple of screws underneath and a couple at the top


well done Andy it is the pump


where can i get a replacement?


where can get instructiosn on how to fit it?


also I'm not sure of the model #, but it is a turbomax


p.s. I was trying to hard ... i was trying to remove the large one-piece cover, but all that was needed was to remove the lower half cover!!!! :-(

***** ***** : The easiest way is to buy a pump but just swap the head with 4 a
***** ***** : Allen screws
***** ***** : Just drain the system and swap the head
***** ***** : Try this;
***** ***** :

Did you get my last comment? I said well done, then I clicked excellent ... but for some reason I am back on this screen and I don't see your rating showing up ... any thoughts?


I'll try again

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