How many times should one need to bleed a rad

Morkin

I recently had a very obvious leak (lost all pressure when a soldered joint on the input feed leaked badly) in my gas central heating system fixed and all rads balanced.

This was about 10 days ago and every few days I've had to bleed the towel rail in the upstairs bathroom - makes sense as this is the rad at the highest point in the house. It's not by much but the top horizontal bar (of 12) is 1/4 to 1/2 cold/air filled every couple of days.

All other rads are fine and there is no sign of leaks around them or in the ceiling or around the boiler.

Is it normal to have to do this after a system has been essentially drained and refilled? Will it settle down after a while or should I get the plumber back in and if I do will he be able to do much more than the inspection I've done?

All input appreciated,

Thanks,

M.

crosstownk

As you bleed, you will reduce system pressure. Is your pressure gauge reading approx 1 bar when the system is cold? If you are constantly bleeding and not topping up then you may not have enough water in the system, resulting in pockets of air throughout the system.

JamesM

As Crosstownk said, make sure that the pressure is at 1 bar.

There is always a lot more oxygen in a system after it has recently been refilled. It's probably not a lot of air - it might not show up in a rad, but it is affecting the narrow pipe in the towel rail. I would give it a while more before worrying.
Jim.

2 stroke

Have you corrosion inhibitor in your system. I've found it can cure this problem where there is no other obvious cause, but I've never used it in a presurised system.

Morkin

Thanks for all the replies - puts my mind at ease for the time being.

Pressure is about .9 bar when cold, 1.5 ish when running. Seems okay.

Dunno about the corrosion inhibitor but I saw that stuff and some sruff you can add to fill pinhole leaks etc. Any opinions on these additives? Are they simple enough to add?


Cheers,

M.

10-10-20

There is a ProTex (??) range of kits available in Woodies which is added to the system by means of a rubber bung placed into the removed vent hole - I have the bottle of ProTex rust inhibiter at home - I just need to get the bung now!
It's cheaper than the stuff Chadwicks have - at €80!

Morkin

That's the stuff I saw. Would you post here on findings after using the stuff?

Would be helpful - maybe as a sticky even.

Cheers,

M.

2 stroke

I'd use the Chadwicks stuff, it works. If your problem is internal corrosion, due to the different combinations metals in your system, €80 is less than a plumbers call out charge. Also property damage from coroded prumbing may not be covered on your insurance.
Don't forget to drain off some water first, You dont want to remove one of those bungs at 1 bar of presure.