New filling loop opposite way round to the old one. Or is it

[Albumen]

I bought a new flexible filling loop to replace the old one, as per this thread:

//www.diynot.com/forums/plumbing/leaking-filling-loop-and-two-of-them.361230/

Just looked at the new one and it's the opposite way round to the old one, by which I mean:

Old one, DVC on cold mains supply, with arrow pointing to the braid, isolator valve on the CH return end.

New one, DVC has arrow pointing away from the braid etc. etc.

Then, I looked. I'd assumed that the connection from the valves to the braid is something like the tap end of a flexible tap connector, with a washer and everything. But it looks like a compression joint to me, same thread, shoulder for the olive. Only difference is that the braided thing has an O ring and goes inside the valve body.

So am I right in thinking that I can connect these whichever way round I like, as long as the arrows on the DCV/Isolator are pointing in the direction of flow?

Two reasons:

1. The only thing that's actually leaking is the Isolator valve, from the tap spindle, as far as I can tell. So that's all that actually needs replacing.

2. Once I've worked out how to isolate the flow and return on the boiler itself, I can use the isolator valve as a drain off point on the return, for reverse flushing the system (there is ALSO a built in filler which connects mains to flow, and there's a system drain on the flow, for the opposite flush). Ecotec Plus 831 combi.

Thanks.

 

[mickyg]

yes they can go either way, you don't have to have a filling loop valve, any valve will do the job as long as you have an nrv in place which technically should go on the mains side, but its no big deal either way.
Take you dont use the inbuilt filling loop in the boiler then

 

[Agile]

I am still not sure that you have got the correct filling loop!

The water regs type is the only correct one to use now.

It has a non return valve and isolating valve and that goes on the mains supply side.

At the system end is an isolating valve only! That can be useful because you can use the flexible hose to depressurise the system!

Tony

 

[Albumen]

Thanks for the swift answer. So those fittings are just standard compressions?

Simpler for me if I can just take the Isolator off. Of course if I'd known that's all I would have bought.

Embarrassingly I didn't know it had an inbuilt filling loop. When it was installed the engineer showed me the one between mains and return, where the pressure dial was on the boiler etc. etc. And that's all I've used since. It was only when I was grovelling around underneath the boiler yesterday to take photos that I saw the in inbuilt one. The Vaillant installers manual says it shouldn't be left in situ, but they have.

So would my DIY flushing idea work.

1. Use the 'extra' filling loop to put cold water into the return, hose onto the drain off (which is connected to the flow), do one radiator at once as described etc etc.

2. Use the inbuilt filling loop to put cold water into the flow, take the flexihose off the extra filling loop (boiler end) and connect something (?) to the isolator valve to drain? There's an arrow on that too, but does it matter?

 

[Albumen]

Agile, thanks for the reply. This one, as sold and configured, has a DCV on the supply end, and an isolator on the system end. At least the way it's connected.

If that's not up to regs then I can take it back to Toolstation and quote WRAS section XXX. Do you know what XXX is though? I'm sure it's sold as WRAS compliant.

Thanks.

 

[Albumen]

In fact, I've just realised, thanks Agile, that my reverse flushing method wouldn't work with this, because I'd have an open mains.