One flow two return heating system??

[pip]

Hi, looking for some info. I've got an old space saver 38 to replace with heat only baxi but the old boiler has two return pipes going to it. So can I join the two returns together, can that be done? I've been racking my brain to see if that will cause any problems, all I can think of is possibility of rads heating up when hot water only is on! Any advise would be greatly appreciated.

 

[mountainman]

How do you know that you have two returns?

 

[pip]

How do you know that you have two returns?

There's one 22mm flow and two 22mm return pipes they are marked in pencil "return" one is for hot water return one is the rad return. Both returns go into either side of the heat exchanger at the bottom the single flow pipe comes out from the top of heat exchanger!

 

[SimonG]

Is it gravity hot water?

 

[Killy Bing]

You're fitting the boiler?

 

[pip]

Is it gravity hot water?

No, it's all pumped.

 

[SimonG]

S plan or Y plan?

 

[pip]

S plan or Y plan?

It's a y plan

 

[GasmanxxxR1]

If ones the hw return and the other is the ch return, then teeing them together before the new boiler is no different to what the old boiler is doing now,

No issues with backflow to rads on s or y plan

 

[Roger Welton]

or could be a combined f+e going back to the boiler

 

[pip]

Thank you very much for the replies