Vaillant Turbomax 828E won't repressurize

[insx]

Hi

The pressure on my 828E is showing zero. I've opened the cold water mains and the CH return valves but no water flows in. I know water is reaching the end of the fill loop (braided hose).

What could be preventing the system from taking in water?

Can low pressure in the CH system affect the DHW side?

Thanks
insx

 

[john90]

is the braided hose (filling loop) separate from your boiler ? If it is, you shouldn't be touching any valves on the boiler. Just the ones either side of the filling loop

low pressure can stop the boiler working for dhw. If your talking about temperature issues, then that's a separate fault

 

[insx]

The filling loop is integrated in the boiler. I have just tried opening the valves either side. However, the end of the loop was only hand tight and I loosened it slightly and water dribbled out so I know that it is getting that far.

The HW issues are hot/cold/hot/cold and F24 faults.

 

[insx]

This is just curiosity now as I'm sure it's not something I can fix but what could be stopping the system taking in water when the entire filling loop including both valves are known to be good?

 

[SpecialK]

Do you know both filling valves are good or just the one?
Sometimes the plastic handles turn but not the valve. Can you remove the handles and turn valve with a spanner?

 

[Agile]

Blockages sometimes occur where a boiler filling flow meets the heating circuit.

Tony

 

[insx]

I know both valves are good.

 

[insx]

We had a plumber fit an external filling loop (in retrospect I could have done that myself but he was good value anyway). It works but I may never know where the blockage is.

 

[GuessMan]

Sounds like the pressure gauge tube is blocked, and as you have hot water problems the plate heat exchanger will probably also be blocked. No biggie for your boiler guy to fix, around £200, job done.