gravity feed radiator heated slowwwwwww.

[vern]

my system is:

F&E tank,
boiler gravity hot feed to cylinder and 2 radiators in both bathrooms.

a central heating pump for all other radiators in the house

no motorise valve, no cylinder stat,
but only a room stat.

I have drained down the system entirely today, but after i refill it, all the radiator on the pump system are hot, but the 2 radiator (gravity feed) in the bathroom doesn't.... my hot cylinder doesn't even heat up properly.

I have tried turned off both radiator and the hot water was only pushing slowly to the hot cylinder, but not good enough to heat it up.

i dont think there is an airlock.... all radiator are bleeded starting from the bottom one to the top.

any advice please?? what can i do??

 

[Softus]

I would say that this is an airlock on the gravity circuit.

Do you have any other vents, either above the boiler or in the airing cupboard?

 

[kevplumb]

what boiler

 

[vern]

boiler is "potterton kingfisher II"

i have tried running some water out from the radiator, it slowly get warmer & warmer, but after i close the valve it goes back to cold.

i also loosen the hot inlet (from boiler) on the cylinder, there are no air and water comes out.

 

[kevplumb]

pull the stat no pump on
but be carefull

wait for the rumble then put it back QUICK

then bleed the rads

 

[vern]

I would say that this is an airlock on the gravity circuit.

Do you have any other vents, either above the boiler or in the airing cupboard?

... there are no other vent on the gravity circuit or cupboard

there is only a drain valve near the bolier where it goes into the boiler and to the central heating pump.

The system was working fine before i drained it...

 

[Softus]

vern, follow kevplumb's advice - he knows what he's doing.

 

[kevplumb]

it would be it was full of water

 

[vern]

pull the stat no pump on
but be carefull

wait for the rumble then put it back QUICK

then bleed the rads

pull the stat???

could u please explain a bit more what u trying do?

Do i turn on both HW & CH then pull the stat off !?!

Could I just turn on both HW & CH, then turn the stat to min. temp? and wait for the rumble then turn it back on??

what happen if it doesnt rumble?

sorry for all the questions.......many thanks in advance!

 

[kevplumb]

pull the stat???

dont turn the pump on

take the thermostat phial out of the pocket on the boiler
you may need to remove a split pin

then light said boiler sit back and wait

it will rumble

then bleed the air it has just pushed out

 

[vern]

pull the stat???

dont turn the pump on

take the thermostat phial out of the pocket on the boiler
you may need to remove a split pin

then light said boiler sit back and wait

it will rumble

So i turn on both HW & CH and set the room stat to min. temp? or just turn on HW only?

pull out the thermostat phial out,
once starting to rumble, then put it back in.

what does this do to the boiler actually?
will it harm the boiler?..... i dont want to break it...

thanks

 

[kevplumb]

no put it on hw only
it will boil the water in the boiler
no it wont do any damage as long as you put the phial back
if you have msn log it in and get mine from my profile

and i will talk you through it

 

[Softus]

kev, would it be prudent to point out to any other readers that this advice doesn't apply to all boilers, just in case they all go off and try it?

 

[kevplumb]

tis fun trying to do it with an apollo
now that does take experience and bottle

tends to be best with c/i heat exchangers

which most of the old systems have

why do you think i asked the poster what the boiler was

 

[Softus]

tis fun trying to do it with an apollo
now that does take experience and bottle

Haven't tried it with that.

tends to be best with c/i heat exchangers

Yup - I know

which most of the old systems have

Yup - I know

why do you think i asked the poster what the boiler was

I knew exactly why you asked, which is why I shut up and let you get on with it. I was just concerned in case some bright spark decided to try it with a non c/i h/e