Centrl Heating Not Working

[espee]

My central heating suddenly stopped working. Well I was having shower (my shower is a simple mixer tap) and the hot water stopped coming from the shower. After that the hot water system is OK but heating seems to have gone wrong. I do not know much about my system but I have a mid position actuator (drayton) which is at the mid position. The tank in the loft HAS water in it. I seem to have a little pump in the airing cupboard (GRUNDFOS SELECTRIC) This pump has a small lever on the side with 3 positions (indicated by 1, 2 and 3 lines) It was set on 3 lines and this pump seemed to make some noise. I am sure this noise has started since the heating stopped working. I moved this small lever on the pump to the 1 line position and it does not make that noise. One of the upstairs radiators is completely cold with the pipe being cold as well. The other radiator is a bit hot but not as hot as it should be. The downstairs radiators are also cold. Its as if something has suddenly gone wrong.
The pipes above the little pump in the airing cupboard are very hot. Any suggestions? I have never bled the radiators since I moved in the house about 1 1/2 years back.

Regards,

Espee

 

[kevplumb]

how many tanks in the loft ?

 

[espee]

2 tanks in the loft. The smaller one according which i think is feed to the heating system has water in it.

 

[breezer]

2 tanks in the loft. The smaller one according which i think is feed to the heating system has water in it.

does that mean the other one is empty?

 

[espee]

No. I am sorry if it sounded like that. I thought the other one is irrelevant for my problem so did not mention about it.

 

[kevplumb]

try bleeding the rads then after that the pump / big screw in middle

 

[espee]

I will try that today. I could find the bleeding thingy on the radiators but not sure about the pump. I assume you mean the big chrome screw in the centre of the pump. Do I need to remove it completely or just loosen it a bit and once water starts to come out, close it again? Do I do this when its running. (Electrical -> )Actually it is connected to the mains supply directly and there is no switch. I assume its permanently connected.

 

[kevplumb]

just loosen it and put a ras under it water may be hot bleed the rads with system off
there is usually a vent point near the mid pos valve as well

 

[espee]

As I havent played with such systems at all, I am a bit nervous, but there is always a first time. This is what I'll try next
1) Switch off the heating from my control panel. (do i need to switch off HW?)
2) Find the bleeding key
3) Bleed the radiators.
4) See what happens
5) If I get air out and water emerges from radiators, I'll switch on the system. If it doesn't make any difference, I'll bleed the pump.
6) Again I'll see what happens.

Today, after spending the night in cold, I am thinking all my radiators have only air and nothing else. The radiator in one bedroom (same where airing cupboard is) seems to be a bit lukewarm.

oh yes, what is a ras as in "put a ras under it"

One more thing is, my boiler seems to start up less often now and for less time, as if the CH is not demanding anything at all.

 

[kevplumb]

rag

switch everything off

 

[espee]

Bleeding the radiators, they have water in them. When I opened the bleed thingy, the water came out with force.

The vent (a pipe with dead end havin a cap on it ?) which was next to the mid position actuator, when I opened its cap, nothing happened but after about 30 - 40 seconds, water came out but it was dripping rather than coming out forcefully. I closed it. Then I loosened the big screw in the centre of the pump and water started to come out. It was, again, dripping rather than coming out with a force.

Any thoughts?

Secondly, if (I assume that) the pump is working fine, is there a way to test the mid - position actuator?

 

[kevplumb]

lever on the side usuallt says man / auto try locking it in man

 

[espee]

I could not locate anything saying Man / Auto.

On one side of the actuator, there is a lever and position markings as
W M H Currently the lever is stuck on W.

On exactly opposite side of the mid-position actuator, there is a small lever which I can press in but that lever does not have anything written on it.

Any thoughts?

 

[kevplumb]

can you remove the actuator

 

[espee]

Oh I see what you mean. I was thinking that the valve and the electrical box above it is one thing but looks like they are different. Does the electrical thingy (actuator?) move the valve? and you want me to remove the electrical thingy only?