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By clive of india
Hi Guys

Can someone shed a little light please, I’m going to replace the pump head on my central heating boiler and I’m not sure about a few things.

1/ Is item one in the photo used to increase and decrease the pump speed?

2/ If it is, am I correct in assuming turning the screw in the direction of the arrow (anticlockwise) increases the speed?

3/ On the top of the pump is an automatic air vent, so after I’ve replaced the pump head and I’ve refilled the boiler with water will the pump automatically vent itself through the air vent on the top?

4/ I can see a small plastic screw on top of the auto vent, do I need to open it to help expel any air?

5/ Should boiler be off whilst venting the pump?

I don’t want to get it wrong as I’m sure the plump should not be run dry?

If it’s any help the boiler is a Baxi Duo Tec 33 HEa and the existing pump is as shown in the picture.

Thanks to anyone who can help

Clive ... RHoCQ1Q5Gt ... wOqrE7OUsD
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