Replacing 3 Port Valve Body

[Adamk270]

Hi everyone,

I have a 3 port valve which has seized in the mid position. I've checked the motorised head and that is working fine.

The 3 pipes to the valve each have an isolation tap on them. I'm just wondering if I can replace the valve without draining the system if I close these three taps?

Thanks in advance.

 

[terryplumb]

Gate valves are notorious for not fully closing ,and you have 3 of them to contend with !! Probably wiser to drain system.

 

[oldbuffer]

1. I think its worth trying to turn off the gate valves. The ones fitted to vertical pipes will probably be OK. The one fitted to horizontal pipe more likely to let by.
2. Turn off the valves. If stiff, remove handles and use a spanner. If any won't turn with reasonable force, abandon and proceed to drain down.
3. Carefully loosen the compression nuts to each valve inlet and make sure each pipe is loose at its connection to the valve. This will allow remaining water in pipes to drain. Plenty of old towels, an oven dish handy. Wet vacuum ideal.
4. If water stops, or flows only at a manageable rate, fully undo nut and remove pipe from valve. One at a time, and be ready to push back together if water flow increases significantly.
5. If water flows too feely, retighten nuts and proceed to drain down.

 

[Adamk270]

Thanks for the advice. I will give it a go once the new valve arrives. Cheers

 

[Adamk270]

Quick Update: All the gate valves were working fine. Fitted replacement no probs. 15 minute job. Thanks again for the advice

 

[Alex evans]

Quick Update: All the gate valves were working fine. Fitted replacement no probs. 15 minute job. Thanks again for the advice

Sorry to start this thread back up. But i too need to change my 3 port valve. When hot water is on.. the rads gets hot too!

Did/do you need to turn the GAS off? Obviously il turn the electric off at the fuse board for the wiring in the new motor.. but my reserch regarding gas seems to be inconsistent.. my boiler is old, i dare'nt try to extinguish/re ignite the pilot.

Thanks

 

[terryplumb]

You do not need to isolate the gas,but you do need to isolate the electrics.

 

[Harry Bloomfield]

Did/do you need to turn the GAS off? Obviously il turn the electric off at the fuse board for the wiring in the new motor.. but my reserch regarding gas seems to be inconsistent.. my boiler is old, i dare'nt try to extinguish/re ignite the pilot.

All you need to do is enure the boiler does not fire up, you should be able to do that by isolating the heating systems electrical supply - no need to turn the gas off at all.

 

[Alex evans]

All you need to do is enure the boiler does not fire up, you should be able to do that by isolating the heating systems electrical supply - no need to turn the gas off at all.

Surley the pilot light will remain? If so, i assume thats okay.. afterall.. none of the work is in/at the boiler.

 

[Harry Bloomfield]

Surley the pilot light will remain? If so, i assume thats okay.. afterall.. none of the work is in/at the boiler.

Yes, if your boiler has an old fashioned pilot light, then that will remain lit - even with no power to the boiler.