discharge from sealed central heating

6 May 2013
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United Kingdom
Hi guys. Just having my gravity fed system updated to a sealed system with a vessel in the loft.

Does the discharge from the pressure relief valve need a tundish and discharge pipe like the unvented cylinder or just a discharge pipe and can it be connected to the discharge pipe from the unvented cylinder or does it need to be a separate one.

Also should the vessel be insulated as it is in the loft? I guess so.

Thank you.
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One hopes you have a qualified installer who knows all these things?

Tundish is useful but rarely fitted for that and particularly not in a loft.

If adding discharge to the one used for unvented then larger pipe sizes might become needed.

Thanks Tony. Yes the work will be carried out by a plumber, I'm just getting my head around it where I want everything to go.


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