Vaillant ecoTEC pro, filling loop problem.

[HelenRH]

Hi

Wonder if anyone here can help? Woke up this morning to find error F.22 flashing on my 2yr old ecoTEC boiler. Looks like the pressure has fallen too low and the systems shut off. I believe you have to fill the system using the silver flexi u shaped fill pipe that's under the boiler? Mine doesn't have a black lever like I've read else where, just a valve on each side that you can turn with a screw driver.

The right hand valve will turn, however there is no movement whatsoever in the left hand valve. On taking a picture the thread looks dodgy. I've never had to correct the pressure since the boiler was installed so have never touched these valves myself.

Can someone take a look at my photo and advise? What is the little hexagon shaped bit in front of the valve for?
Any advice would be appreciated

Many thanks

 

[oldbuffer]

The hexagon bolt head is the top of a check valve. Used to stop water going back into the mains from the boiler return if the valves fail.

If the left hand isolation valve really cannot be turned, it will have to be replaced. Probably easiest to replace the whole filling loop with something like the BES part No. 15583. You can get equivalents from Screwfix and the like.

However, to change it the cold supply will have to be turned off and the system drained to below the level of the loop. When refilling, don't forget to add inhibitor. Alternatively, shout off the cold mains, and freeze the boiler return either side of the left hand filling loop valve.

 

[mogget]

You may have already tried this, but the left hand valve (integrated with the check valve) must be turned anticlockwise to open.

 

[HelenRH]

Hi thanks for all your help. Managed to get some pliers round the valve and with a bit of force and gritted teeth it's turned. Pressures all back up now