Gate Valves or Isolation valves for 22mm Flow and Return??

[dja]

In resiting my boiler I'm putting in some improvements. One is to introduce some way of isolating the radiators from the boiler so that if I have to drain the boiler I don't have to drain the whole system. My plan is to put valves in the Flow and Return close to the boiler. However, I bought some 22mm Isolation Valves but noticed that the actual bore is nearer 15mm and I'm worried they would restrict the flow too much. My alternative would be to use Gate Valves, but would these be any bigger bore. Any advice appreciated.

 

[chr15]

You would be better off with full way gate valves as they do leave the full bore-you can also get 1/4 turn full bore lever ball valve which are better quality than gate valves-choice is yours.

 

[dal5band]

They may seize up with the heat anyway unless you remember to free them every year !

 

[ChrisR]

If you use cheap ffball valves you'll have a couple of fountains to deal with...

 

[wilhelm]

why do you want to isolate boiler? is it that special

and the gate valves wont work when you come to use them anyway

 

[giblets]

What boiler do you have?

 

[dja]

Boiler is a Potterton Flowsure +.
As to the other replies, is it not a good idea to be able to isolate the boiler so the whole system doesn't need draining if the boiler needs to be worked on?
Also, what valves would anyone recommend.

 

[Bahco]

Can you not turn the isolating valves off at the boiler where it joins the F and R pipes

Check your manual.

You should not run the boiler for long periods with the circuit closed off though.

 

[dja]

My boiler doesn't have any valves in the Flow and Reurn, that's why I want to fit some. But it is purley for easier maintainence and to save draining the whole system radiators and all, when I could get away with draining just the boier.

 

[chr15]

Boiler is a Potterton Flowsure +.
As to the other replies, is it not a good idea to be able to isolate the boiler so the whole system doesn't need draining if the boiler needs to be worked on?
Also, what valves would anyone recommend.

Any valves are better than no valves so a couple of good quality gate valves wil do.

 

[giblets]

Looking at the manual for your boiler it looks like there are isoloating valves already fitted. Obviously been left off by the installer.

Would suggest full bore valves of a good quality. Plumb Center do them for gas (but can be used on water). Not cheap and you would need to remove the lever handles.

 

[dja]

The only valves I can find in the Flow and Return are on each side of the pump, which will be useful when time comes to change the pump. But they won't isolate the whole boier from the radiator system.

 

[giblets]

DJA, have modified my last post

 

[dja]

Giblets, many thanks, I've spotted the ones you mean in a catelogue. I'll use those.