Reading various websites it seems to me that it's a bit like an urban myth. Switch off the CH system before bleeding ....as air can get in.
Yet no-one can explain how this particular myth has gained credence. I can understand how it might ...nb might..happen if the pump has been incorrectly fitted in the return but not if it is in the flow.
If the pump is fitted in the flow then there is no need to switch off, I maintain.
Yet no-one can explain how this particular myth has gained credence. I can understand how it might ...nb might..happen if the pump has been incorrectly fitted in the return but not if it is in the flow.
If the pump is fitted in the flow then there is no need to switch off, I maintain.