Vaillant eco tec plus 831 pressure issue

[Alexa777]

Hi, I've got a Vaillant eco tec plus 831 and it had the error code F75 Fault: Pump/water shortage. I'd noticed earlier that the pressure bar looked low but not thought much of it until the heating didn't come on and I saw the error code. I thought I knew what to do and turned the 2 taps underneath to let more water in for about 10-15 seconds. Then the system refired and the heating came on. However, I think I may have overdone it as it's flashing 3.7 and I suspect that may be too high. I've tried running a hot tap but that doesn't seem to make a difference. Any tips would be very gratefully received! Thank you

 

[Deleted member 267285]

F75 is often a blocked sensor, sometimes a failed pump. Yes 3.7 is far too high and it won’t work. You need to drain the water out, although I suspect the pressure relief valve has operated as they’re designed to open at 3 bar and above.

 

[Alexa777]

Hi Chris,

Thank you so much. I guess the pressure is my fault... it did work in terms of kick starting it to work again. It's now down to 3.3 (I did run the bath in case that helped) and the heating will be going off soon... I'm not sure how to drain some water out though?

Thank you so much again,
Alexa

 

[Alexa777]

That's weird, I hope good weird, it's stopped flashing the pressure and now just says 47 degrees C. the bar on the right does show the level as at the top line so I presume just inside acceptable I'm thinking maybe I've got away with it... the heating has just gone off so maybe that helps too? Do you think I need to do anything or just keep an eye on it? I do need to book a service anyway.

Thank you again,
Alexa

 

[jeff the gasman]

Needs a proper service and the expansion replenishing. Get a local recommended gas man in!

 

[Alexa777]

Thank you very much, I will get back to my usual gas company.

Thank you again to everyone for your advice