System boiler pipework question

[AMEdinburgh]

I'm trying to understand the workings of a system boiler as I'm considering a switch from a combi to a system and sealed cyclinder.

Am I right in thinking?

With the central heating, the water is pumped through the heat exchanger through the supply pipe to the rads, back via the return pipes to the boiler. When the boiler is heating the DHW does the some of the same circulating water, in effect, get diverted to feed the coil in the cylinder and back to the boiler?

The reason for asking is that I currently have installed quite a large pressure vessel which will need to be moved and there is a potential space in the tank area but then it would be on the tank "circuit" rather than on the CH "circuit".

Would that work / be allowed?

Thanks in anticipation

 

[twgas]

You are correct in your thinking that the CH water circulates through the coil, so the expansion vessl should be ok near the cylinder.

 

[AMEdinburgh]

thank you - good news

 

[kevindgas]

so the expansion vessl should be ok near the cylinder.

if its a system boiler it would be within the boiler! on the other hand if its a heat only boiler then it will be seperate and can be fitted anywhere in the heating circuit