Fitting new isolating valves on circulating pump

[mw01908]

Hello

I did a search to find any other posts on my dilemma but couldn't really find anything that was quite the same as this problem....i'm replacing the pump on the central heating because it is weak. But the valves have no effect when they are turned off. I tried with a pair of pliers to get them as hard shut as possible but no luck. (They have no red wheels)

1. How do I fit new valves on? Are they compression joints? Or is ptfe tape enough for this? Is it easy for a diyer?

OR: idea 2. I am draining the system down to change the pump, so would it be easier just to leave the valves alone? Only problem with this is that the valves did have a lot of corrosion on them which has gone since I have moved them, but now they do leak slightly from the shaft. I wonder if this is because of the corrosion or because I turned them off so hard and damaged the washers?

Can anybody please advise

 

[ollski]

The best plan for diying it is to drain down the system to below the level of the pump and then remove the pump first and then replace the valves aswell. You can leave the old compression nuts and washers from the old valves, they will fit fine.

 

[Nige F]

The valves don`t have washers.they`re gate valves..and cheapo ones @that The new ones will come with a couple of thin fibre washers....do smear them with some jointing compound before assembling to pump .otherwise you may get an air leak on suction side of pump in to system.and you`ll be posting again

 

[ollski]

sorry meant olives.

 

[mw01908]

Thanks. The pump has come with a new set of washers. Are these the same?

What I need to know is how to seal the valves to the pipework when replacing them...? Is there a special way?