Ideal Classic Boiler/New Pump/Airlock?

Hello - hope that someone can help me.

A few weeks ago the central heating started making alot of noise - gurgling. Air had got into the system (i don't know how). Bled the rads and alot of air came out of the upstairs rads. (5 upstairs - no idea of order or how to guess) Nothing but water coming out downstairs.

Loud squealing/scretching noise from pump then. Pump was too hot to touch so concluded that it had run dry and bearings shot.

Bought and fitted new pump. Seems to work ok. However, boiler now cuts out 20 sec/2 min after firing - pilot light goes out. No problems with boiler and am confident this is safety cut out. (Ideal Classic boiler, house and bolier approx 8 yrs old. Boiler serviced annually). Am assuming cut out is due to no water moving through boiler?

Downstairs rads fine - water coming out when I bleed valves (probly just lying water level though?) Upstairs rads have no air or water coming out of bleed valves. Have tried running pump with them open but nothing. Can't get a hiss or a gurgle.

Have tried bleeding the pump too, with discharge valve in both open and closed position.

Old pump was set to highest speed, but have only tried new one on middle seting to save damaging it whilst this is getting sorted.

Is this an airlock? How do I fix it if it is and what could it be if it isn't??

Many thanks.

Header tank dry ?
Cold feed blocked?

Heading tank all appears fine - balcock floating/water inlet working. Not sure what mean about cold feed. The pipe out of header tank has a mesh over it. This is clear.

The cold feed is the pipe out of the bottom of the small tank that feeds the CH system. With the symptoms you have described and the fact the tank is full its odds on it is blocked.

Thank you. Is there a simple way to fix this?

Classic air locking of cold feed from F&e tank, try opening the heating system drain and drain off some water to get the water moving down the cold feed into the system, remember to bleed the pump through its rotor end screw, if that doesnt allow gravity to kick in and fill the system then there is a fair chance its blocked especially if it s been piped with a U bend at the point it enters the system........ good luck

Kristoflampie said:

Classic air locking of cold feed from F&e tank, try opening the heating system drain and drain off some water to get the water moving down the cold feed into the system, remember to bleed the pump through its rotor end screw, if that doesnt allow gravity to kick in and fill the system then there is a fair chance its blocked especially if it s been piped with a U bend at the point it enters the system........ good luck

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hi

we are having the same problem, a couple of weeks ago i was woken up by the sound of water rushing through the pipes, after reading this forum everyone says its air in the system so i have bled the bathroom rad daily,(the only one that keeps hissing out air) all the others have been ok.

this morning i was woken up by a terrible squealing noise which sounds like its coming from the circulating pump (new last year) none of the rads have come on & the bathroom rad is only dripping water out of it (no air)

my husband went up in the loft yesterday & the smaller tank was full, we are not sure where the heating system drain is so if its blocked we dont know what to do

please please can someone help

thank you

sarah

Follow the pipe from the bottom of the small tank to where it joins (tees) into the heating pipe work.

If it is blocked, it will be at this tee.

Needs cutting out and replacing if it is blocked.

thanks dave

sarah

Dont bleed the rads with the pump operating. You may pull air in.

Your pump is not there to push air out, and depending on your c/f & o/v configuration it may be possible with a small amount of debris, that your neutral pressure point on the system will now pull air in.

Pics will help.

Paul

thanks guys for your help but i think its ok now (fingers crossed) somehow the tap in the airing cupboard wasnt fully on.

yesterday morning after posting my question i went & fiddled about with things & i moved the tap & a bit of water came down the pipe so i think with that being not fully open the pump was dry.

anyway the heating has come on this morning, no noises at all & when ive checked the rad in the bathroom (heating off) all that comes out is water.

thank you very much for help

sarah

You shouldn't really have a gate valve on the cold feed of a heating system. I would recommend that you open tha gate valve fully and remove the wheeled head to prevent this from being shut accidently in future.