help with F&E pipes

[billy45]

Hi All. first post so bear with me.

BG came out to repair boiler. When he looked at my system he told me it was piped up wrong.

currently piped up as follows : expansion pipe, cold feed pipe, then pump. He advised that this be changed as it was drawing air into the system. Suggested pump, then cold feed, then expansion. Is this right or unecessary. Other options welcome

 

[chrishutt]

Firstly what you call the expansion pipe is actually the vent pipe, and the cold feed is the feed & expansion pipe.

The normal arrangement on the flow pipe from the boiler is first the vent pipe, then (within 150mm) the feed & expansion pipe, then the pump, then perhaps a by-pass and any motorised valves. In other words your arrangement is right and the BG guy is wrong (why on earth did you call BG in?).

As for drawing air in, how do you know this is happening?

 

[Softus]

currently piped up as follows : expansion pipe, cold feed pipe, then pump.

Is what the BG engineer said? Have you double checked it?

Going in the direction of the arrow on the side of the pump body, can you tell us which order those three things are piped?

If you can't see an arrow, can you describe what the pipework goes to after the pump (i.e. after the pump valve)?