Radiator Bleeding/Topping Up

[Karl_W_UK]

Hi there...

i bled my 1st floor radiators earlier as the tops were cool but the bottoms were hot.

I cant however find the place where I need to top up the pressure in the system.

There is a potterton combi bolier in the corner of the kitchen, and a flexcon pressure gauge under the sink whic is nearly on 0bar, but i cant see a way to add more water into the system to bring pressure up.

Any idea or anyone familiar with these brands?

I suspect I have left important info out that might help to hlep me, so please let me know!

thanks.

[Steve Walker]

Look for a steel-braided flexible hose with a valve on it. Should be somewhere directly beneath the boiler.

With one eye on the pressure gauge, open the valve and top-up to 1 bar.

[Richard]

If it's anything like my pressurised system there should be a lever switch on the pipe work, (in my case near the pressure gauge) which you turn to allow additional water into the system, when you reach the operating pressure (in my case 1 bar) turn the lever back.

[KW_UK]

there is a red plastic cap on top of the gauge, with arrows pointing in an anti clockwise direction, yet if you turn this, it acts like a cap for a medicine bottle; it keeps clicking round and round.

I found that turning it slowly, and holding it works, bu the pressure drops when doing this.... not goes up like i was expecting. i must be doing something wrong?

the only braided hose i can see nearby is for the sink, i dont think there is a lever nearby either...

[Steve Walker]

Mmmm, that sounds like a pressure relief valve. Many very excellent plumbers hang out here (uk.d-i-y), if you can wait 12hrs you'll get expert advice. Otherwise, can only suggest you google for a potterton maintenance page or manual?

[Rob Morley]

The filling loop should be disconnected when not in use. Assuming that this has been done, look for a hose and somewhere to attach it to.

[Andy Hall]

That is the pressure relief valve. It's designed to open automatically if the system pressure should go too high. Turning it is a test function which releases some water and so the pressure will drop. Just for reference.... Doing so is not a good idea because you can get bits of crud from the system stuck in it and provoke a small and steady seepage which is difficult to fix.

You need to look further. POssibly there or somewhere within reasonable distance (a few 10s of cm) of a cold mains water supply, there should be a threaded fitting about 25mm across. Nearby, there should be a similar one on the cold mains supply. They look rather like washing machine valves typically. There should be a braided hose to connect the two, although that is supposed to be removed after use so may have been lost.

Have a look on

Then search using 11354 as a prodcut search (not part code)

You are looking for some kind of arrangement like that or perhaps something like 8148, 8165 or 15583 (further down the page)

The hose may have gone missing, in which case you'll have to buy one. Plumbers merchants or B&Q Warehouse have them.

[KW_UK]

Hi,

managed to find all of this, was hidden away and had no lever!

got the pressure up, bled the radiators, the pressure dropped again so topped it up to 1.0 bar.

now the boiler turns on, then goes off after approximately 30 seconds.

can't think why, any ideas?

[Rob Morley]

Airlock? Either in the boiler or at the pump. Just guessing.