Vaillant ecoTec- Can't pressurise with internal filling loop

[bristolbert]

Hi, newbie here.

I inadvertently depressurised the DHW system by fiddling with the pressure release valve, so I now get an f.28 on my ecoTec combi.
There was no manual when I moved into the house last year, so a bit of hunting on here revealed that this model has an internal filling loop. Great, I thought - so I followed this, but I don't hear any pressurisation occuring!

Basically, underneath the boiler at the front, there is a brass cube connected to the DHW return, with a silver-braid pipe going up into the boiler. I turned the grub screw on this, but no joy. The silver-braid pipe seems to connect to some sort of test point with a X head fitting (haven't touched this) and then back up into the boiler near the PRV at the far right.

Does anyone know, is there another valve that I need to open to get pressure back into the system?

Thanks in advance!

Bert

 

[petit_pablo]

There should be 2 black levers on the filling loop, one at each end

 

[bristolbert]

There should be 2 black levers on the filling loop, one at each end

Alas, not. This system doesn't have the filling loop exposed. It's all inside the case.

I suspect that there *is* another valve somewhere, I'm just not sure where!
I've found the installation manual on the Vaillant website, but no immediately obvious solutions.....I'll report back if I crack it.

 

[simond]

This would be an early version of ecoTEC. The later versions have two grey coloured knobs on the base of the unit.

You need to open two sets of brass 90 degree screws, at either end of the braided pipe. It is often easier to remove the lower plastic slatted grille for access, as the cutouts do not always accurately line up with the filling loop.

On the units of the last 24 months this has been addressed, it now has the easiest filling loop in the business.

 

[bristolbert]

This would be an early version of ecoTEC. The later versions have two grey coloured knobs on the base of the unit.

You need to open two sets of brass 90 degree screws, at either end of the braided pipe. It is often easier to remove the lower plastic slatted grille for access, as the cutouts do not always accurately line up with the filling loop.

On the units of the last 24 months this has been addressed, it now has the easiest filling loop in the business.

Ah, I think the PDF I have is of the newer models - the filling loop looks really obvious on there!
Are you saying there is another valve beyond a cutout in the base of the case-proper?

 

[simond]

No, both valves are located behind a white plastic slatted grille covering the base of the boiler. Some lazy installers throw this away - so you may not have it!

The X head fitting should not be touched, that is a non return valve.

The screws you need are at each end of the braided pipe, if memory serves me correctly one end may have a short length of solid tube extending the braid.

Both valves must be open to introduce water into the CH circuit.

Turn them both off afterwards, NB : be sure to use the right size driver as the brass heads can get damaged.

 

[bristolbert]

No, both valves are located behind a white plastic slatted grille covering the base of the boiler. Some lazy installers throw this away - so you may not have it!

The X head fitting should not be touched, that is a non return valve.

The screws you need are at each end of the braided pipe, if memory serves me correctly one end may have a short length of solid tube extending the braid.

Both valves must be open to introduce water into the CH circuit.

Turn them both off afterwards, NB : be sure to use the right size driver as the brass heads can get damaged.

Cracked it!

Actually, Simon, it was slightly different to how you described it (the plastic panel was never present) - there are two brass blocks at the front of the boiler, one at the end of the mains water-inlet and the other, to the right of it, for the central heating return (not DHW as I incorrectly stated in my first post). I turned the one connected to the mains through 90deg first and then let the water in slowly though the other one - see the two screws in the top right:

http://flickr.com/photos/12657637@N00/2524362714/

I then simply turned both back off, reset by pressing the flame button on the control panel and am now about to have my shower!

Thanks for your help guys'n'gals!