No hot water

[londonmark8]

Hi everyone, I hope someone can help. The story goes like this!! I drained the central heating system in order to fit new radiator valves. Refilled and bled the radiators and everything seemed fine, until I realised there was no hot water. Cold water from the hot taps and the cylinder was cold. The boiler is downstairs in the kitchen and I could feel that the "hot water" pipe from the boiler is hot up until about 2 foot below the kitchen ceiling, where it then becomes warm, then cool. As suggested on this forum I drained and refilled the system again to get rid of the (suspected) airlock around the coils in the cylinder. After doing that the hot water pipe from the boiler to the cylinder is red hot, but the cylinder is just warm, as is the water from the hot taps. Could there still be an airlock?? I have also as suggested been into the loft where the F&E tanks are, and fed water down the overflow pipe into the central heating part of the cylinder to try a break any airlock. Any other ideas, causes or suggestions would be really appreciated. Many thanks. Mark

 

[doitall]

Is there an air vent on the cylinder primary pipes.

 

[londonmark8]

Is there an air vent on the cylinder primary pipes.

Hi "doitall", thank you for your reply. No there are no air vents on or around the cylinder.

Regards, Mark

 

[doitall]

Is it a fully pumped or gravity primaries.

Are there any motorized valves, and what type.

 

[kevplumb]

what boiler do you have

afternoon mr dia ive woke up

 

[doitall]

what boiler do you have

afternoon mr dia ive woke up

Evening KP ready for a long night

 

[ChrisR]

fed water down the overflow pipe into the central heating part of the cylinder to try a break any airlock.

How did you do that? Did you just pour it in, or do this:

That only works if the air is in thepipe you're pushing the water down, so have a look - airing cupboard sort of place.

You MIGHT have to "crack open" the upper connection to the cylinder to let air out, if there's no vent.
Be darned careful if you do, it's easy to wreck the cylinder. Use two spanners, one stopping rotation...