At the end of the CH FLow

[WabbitPoo]

Sorry if this is a thick question: I presume the end point of the CH flow pipe (the furthest point from the combi) is connected directly to the end of the return pipe? If so is this why I have a small radiator installed where the old hot tank was: to allow the system to still flow correctly (plus it acts as an airing cupboard I guess)

The grey things on this rad (pictured) are just an easy way of splitting the flow off to another rad? This cupboard is going soon, so this rad will go with it.

 

[Elkato531]

The flow and return pipes are not connected. The water has to pass through a radiator to get back to the boiler. If the radiators all have TRVs there is a possibility that they will all close and that's why a bypass valve should be fitted. The bypass valve may be an integral part of the boiler or could be an external component on the system pipework.

As far as your photo is concerned, the grey parts are manifolds which allow separate flow and return connections to several different radiators. Its a bit untidy but if its in an airing cupboard, at least its out of sight. Not so good though are the iso valves just before the manifolds. They are not designed for heating systems and are guaranteed to leak eventually. They are also quite restrictive and as it looks like the flow for three radiators passes through them you may have problems with those radiators not heating correctly.

 

[WabbitPoo]

Thanks. This whole assembly is going. Might the rad have been fitted as a means of BEING the bypass valve? Or can I just remove it, connecting those spurs in some other way?

 

[oldbutnotdead]

Yes it might have been (usual sign is no TRV). Not permitted nowadays. That manifold setup is fugly...if every other rad on the system has TRVs fitted, the boiler requires a bypass & there isn't one somewhere else then replace that rad with a bypass valve (or link flow & return with a bypass valve somewhere else)

 

[dilalio]

That is a bona-fide lash up!
Get that ballofix isolator (and any others) removed from the CH circuit.

 

[WabbitPoo]

lol I agree its a mess - not guilty.

We have a towel radiator in the bathroom which has no TRV on it and is never closed off, so won't that do as a means of ensuring the system flows?

 

[oldbutnotdead]

Yes it would do, but for £20 in bits and half an hour's work you could do the job properly. You can keep your towel rail in place as is if it suits you, the bypass will only operate if flow pressure exceeds return pressure by whatever pressure you set the valve at. Which won't happen if 1 or more radiators are operating...

 

[WabbitPoo]

Thanks. Might the combi have one "internally" as it were....its a worcester bosch greenstar HE (an HE 30 if memory serves, though I'm not there right now)

 

[oldbutnotdead]

Dunno. Have a look here see if one is required-may not be on that model (no date on the book though) https://www.google.com/url?sa=t&sou...sQFnoECBsQAQ&usg=AOvVaw1nw4v-JEqakn5o6BgyS4vY

 

[WabbitPoo]

I can see no mention of a requirement in the installer's guide, but I'll get one fitted anyway when I can. Thanks