I have a heating system with a BG300+ boiler and a pump/valve for the CH circuit and a pump/valve for the HW circuit. I noticed that both pumps come on whichever circuit is active. When I looked both pumps are connected to the single overrun signal coming from the boiler.
The problems are:
The problems are:
- the CH pump is quite hefty and it's using a lot of power when it's not needed
- Some heated water is getting into the CH system when only the HW system is active. I'm wondering if the CH pump is forcing water past the CH valve which isn't completely closed
- The CH system is always hot when required, but the HW system isn't getting hot enough especially when it's really cold outside.