Back duo-tec won't pressurise!

[ottosump]

Hi group, I have a back duo-tec which I can't depressurize. Tried following the guides provided on the site & you tube but to no avail. Any combination of the valves doesn't alter the pressure. Can't hear any water flowing through the system. Any advice appreciated, regards Otto

 

[gas112]

do you have built in filling loop ? does it have levers or knobs

 

[ottosump]

Yes it has a filling loop (I think) 3 black valves on the rear, all open. x2 black knobs on the front ofset to the right. these are closed. opened them but nothing happens?

 

[Stadan20]

Sounds like stuck checkvalve on filling loop

 

[ottosump]

Sounds like stuck checkvalve on filling loop

Thank you for the response, could you identify the check valve from the attached picture? Regards Otto

 

[gas112]

These wheel ones were a nuisance they turn on by opening them in different directions left hand one is anti clockwise righthand clockwise (i think or vice versa) . check valve is the larger of the two and were prone to sticking you could try giving it a gentle tap with spanner or large screwdriver

 

[Stadan20]

Yup agree with gass 112 , turn left one away from you and right on toward you , vise versa for closing down , but saying that I have had a lot where the plastic wheel head sheers off

 

[dreadnoughtheating]

occasionally you need to fully open them, and I mean all the way to the stop location, to get anything flowing through.

After trouble with the earliest ones, I resorted to putting in 'old skool' filling loops separately to avoid troublesome call-backs.

 

[ottosump]

The left hand check valve HAD seized, I had to remove it and poke about with it before it came free. Alls well now and boiler has been re-pressured.
I've seen a similar set up with braided hose, could i replace these for a braided hose to alleviate further troubles.
Thank you for all the advice guys, much appreciated.
Otto, West Cumbria

 

[holty]

http://www.ebay.co.uk/itm/POTTERTON...641136?hash=item4d47f3ca30:g:vAUAAOSw-YVXl391

Might save a bit of time. Didnt realize how much the kit was though. Got quite a few of these.

 

[ottosump]

http://www.ebay.co.uk/itm/POTTERTON...641136?hash=item4d47f3ca30:g:vAUAAOSw-YVXl391

Might save a bit of time. Didnt realize how much the kit was though. Got quite a few of these.

Thank you for the advice, does seem a little pricey. Does anyone know the part number for the check valve, probably be easier if I just change like for like.
Still working, Otto!

 

[Stadan20]

Or just smash the check valve out