Problem with refilling system

the_other_mce

Can anyone help please? OH has removed a radiator in the kitchen (which is at the 'end' of all the system- and doesn't feed into any others) and has been trying to get the system up and running again. However the radiators (except the one downstairs) aren't refilling!! We have tried bleeding them but very little air comes out and no water seems to be replacing the air. Each radiator has two 12mm pipes on one end. We are stuck.... The boiler doesn't seem to be firing up even though the pilot is alight. Does anyone have any suggestions as to what we can try next?

gardnt1

what type of system is it?

is it supplied via a head tank in loft or by a filling loop on the boiler?

the_other_mce

gardnt1 wrote:

what type of system is it?

is it supplied via a head tank in loft or by a filling loop on the boiler?

Hi - we aren't too sure about this!! There are two tanks in the loft (one slightly smaller than the other) and the boiler is behind the fire in the living room.....
We noticed the boiler did fire up but only for a minute and is off again .....

gardnt1

The only reason i asked is obviously to make sure you have a water supply to fill the radiators up with......with a filling loop you would have to presurise the system via an on/off tap to the boiler, with the tanks in the loft, they should fill via a ballcock.

Sounds like you have a back boiler which is cutting out due to high temperature as no water to heat, but really need a plumber/heating engineer to reply now! If the tanks are easy to access maybe worth checking that water is in them!

one tank probably supplies cold water to various parts of house? other (smaller) one may be the header for the central heating....this is the one to lift lid and check is full.........as said not a plumber so maybe best to wait and see if anymore sugesstions forthcoming!

Canucklehead

Hi

As gardnt1 has suggested look in the loft for the small tank.
The water in it will be quite dirty (as opposed to the water in the larger tank)
Make sure it is full and the ball valve works.
If you have the system programmer on , then turn it off.
Have a look around the hot water cylinder and follow the pipework and see if there is a vent on any pipes (they will be vertical and stop in mid air)
If you have a motorised valve then see if you can find the 'manual open' lever on it.(depends on make as to where the lever is)
Best case scenario; air lock .
Worst case scenario; blocked cold feed.
Did you turn off the rad valve/s to take off the rad? Or drain down whole system?

Corgi Guy.

the_other_mce

Hello,
We drained down the whole system by turning off the mains and left everything running 'til there was no water left, took off the radiator and blanked the pipe just past the radiator tap. Everything went really well until we tried to refill .......
Ballcock seems fine in both tanks - will check pipes now - there is a vent by the tank (black plastic) it twists and says 'open and close' have tried this both ways but doesn't seem to make any difference.
Thanks to everyone for the tips so far - here's hoping we get it sorted without a huge bill. Any idea how much this is likely to cost if it is the worst case scenario??....:eek:

Canucklehead

Ok,

Plastic vent is an automatic air vent. There should be a little cap on the top the same as a car tyre valve cap.It should be loose. Valve should be 'open'
C.G

ormus

sounds like you have a microbore system, which means a manifold to distribute the water to each rad.
i dont know for sure, but maybe the 2 pipes need connected to each other, or they need to be removed completely from the manifold?
then bleed as per normal.

Canucklehead

One more before I go........

You could fill the system the same way you drained it.You need to be VERY careful. The problem is the pressure on filling will make the drain off leak like a sieve!! Fix the hose firmly.Most important is that you will fill the tank in the roof if you are not careful. If the overflow isn't connected properly it will fill the roof too.!
Bit of a last resort if you are not confidant.

Good luck.
Corgi Guy

the_other_mce

Thankyou all for your replies. We decided to try refilling the system by doing the opposite of what we had done already and it worked a treat. All systems go now. Thanks again for the advice - it was invaluable.:T

Canucklehead

Hi

Good news.
Thanks for the update ,always good to know 'what happened next'

Corgi Guy.