recharging boiler expansion vessel

[Fallout]

When wanting to recharging a boiler expansion vessel, you need to remove the pressure from the boiler? However whats the best way of doing this as he valves on the boiler flow and return pipes can be prone to leaking.

 

[Madrab]

Yes, no pressure against the EV. Vent it through the system drain or through a rad. I tend to keep a rad vent open whilst re-charging to allow the system to release the pressure as the vessel is being pressurised.

 

[Fallout]

So as long as I drain the pressure off the boiler its ok can you test the valve to make sure you don't get water out of it ( split diaphragm) before draining?

 

[TCCHeating]

So as long as I drain the pressure off the boiler its ok

Yes. But you need to leave the drain open while you repressurise the expansion vessel because you will be pumping water out of it.

Also when you've finished. Check that the schraeder valve has sealed properly. Good old fashioned spit test is what I do

can you test the valve to make sure you don't get water out of it ( split diaphragm) before draining

Yes. You should do this while there is pressure in the boiler. Push the pin down with a screwdriver to test for water.

 

[Fallout]

If water new expansion vessel if not I cant pump up. Can I ask if you fit and externally expansion vessel do they need to be fit vertically or will horizontal do?

 

[TCCHeating]

do they need to be fit vertically or will horizontal do?

Orientation doesn't matter. Fit it whichever way around you want

 

[St0rmer66]

Don't be too disheartened if you get water initially from the schraeder. Let it all out and still try to pressurise the boiler. It can be condensation. If you have an open end and the diaphragm is genuinely split you won't be able to get it to hold ANY pressure no matter how long you pump for.

 

[Fallout]

So if I did have to fit a new vessel I could.fit it.below the floor between the.joist horizontaly? The pipes.run up the back to the boiler. To the floor space above. I thought.expansion.vessels had to be.fitted horizontaly. Or is tht just for.unvented.hot.water?

 

[Madrab]

Nope, it's a sealed container and under operation is full of water on one side, air on the other, so orientation isn't much of an issue.

I wouldn't site it under the floor though, it's just not really a place to locate an EV.

 

[Fallout]

What pressure do you re recharge to 1.5?

 

[BigSnoopy01]

Check appliance manufacturers instructions.

 

[Fallout]

Nope, it's a sealed container and under operation is full of water on one side, air on the other, so orientation isn't much of an issue.

I wouldn't site it under the floor though, it's just not really a place to locate an EV.

No were realy over to put it. As pipes run up back of boiler so either under the floor above or have it above /to the side of the boiler which is in the kitchen and not boxed in so will look unsightly

 

[Echo the husky]

Where is the existing faulty one??

 

[Madrab]

Possobly need to get a joiner in and box it in then? Honestly, under the floor is just not a suitable place to locate what is primarily a safety device. It just isn't serviceable under there and I'm sure there will be a reg that will reference it.

I assume the PRV/Filling Loop will be connected near the boiler?

Oh, and if you can, try and install the EV as close to the boiler return as you can, keeps the mean temp lower extending the life of the diaphram.