Advice on central heating manifold design

[B_jam]

Hi everyone,

I’m building a central heating manifold with 4 heating zones (27 rads split into 4 zones) and 1 HWT zone (and a 6th spare). I have an oil boiler which is controlled by each zones room stat as well as a back boiler that has all been professionally installed and plumbed in. The two systems are currently plumbed together however only three zones have zone valves which means when the oil boiler tries to heat ZV2, it also heats Zone 1 (no zone valve) and the hot water tank (no zone valve), not ideal. To solve this I plan to add a zone valve to zone 1, and plumb the back boiler flow to bypass the zone vale so it remains unrestricted. I will also add a ZV to control the hwt. My main question is around placement of the non return valves and if there are other things I haven’t thought of yet that should be considered. Thanks for any advice or tips. Attaching a picture of the design

 

[dilalio]

Think you might need to look at a low loss header.

 

[B_jam]

Thanks looks like it could be a viable option. If both the back boiler (solid fuel) and oil boiler feed the LLH and the output circuits are all zoned, how do I ensure the solid fuel has an adequate unrestricted access to Rads?

 

[dilalio]

Then you'll need a heat sink rad but it needs to be enough and can't be zoned.