Radiators working but no hot water.

[dannynolan]

We have a worcester bosch 30 cdi greenstar conventional with a hot water cylinder upstairs with a thermostat limpeted to it.

There are no fault codes on the boiler, and I have reset it a couple of times so the pilot light should be working.

I have looked at the diverter valve and all three pipes A,B, and C are hot, but obviously the hot water cylinder is cold..

Any advice would be very much appreciated.

 

[undertrained]

Is b hot all the way to the cylinder?

 

[dannynolan]

Thanks very much for replying.

The pipe is only just warm when it enters the cylinder.

I have slid across the little lever on the diverter valve to manual position. It doesn't seem to want to click up into position, I don't know if it 'has to' or not, but this hasn't made any difference.

 

[ianmcd]

post a pic of your HW Cylinder, it may be an airlock, and your boiler doesnt have a pilot light

 

[dannynolan]

Thanks very much again, off to a tea dance, will post picture later.

 

[dannynolan]

 

[dannynolan]

The pipes on the left as we look do not go into the boiler - two horizontal pipes on the right do, the upper one is lukewarm and comes from the diverter valve, and of course the pipe exiting the boiler at top middle.

Thanks

 

[ianmcd]

in your pic the small grey box is your HW thermostat, to the right you will see the pipe coming out of the top of the HW coil, it has a T and a short section of pipe pointing up, that is the bleed point for your HW switch everything off and crack that bleed point until there is only water comes out, then turn everything back on again and see if that sorts it

 

[undertrained]

What temp is your cylinder stat set to? Any chance of a better picture of it to be certain? Is it on the cylinder properly?

 

[dannynolan]

 

[dannynolan]

Thanks for coming back.

I bled the

 

[dannynolan]

Two problems now.

I opened the small valve with pliers (though forgot to switch everything off) and bled it. Unfortunately when I screw it back on with the pliers as tight as I can it still leaks. I didn't remove the cap so I doubt it's cross-threaded. I have a grip wrench but I don't know if applying more force would be a good idea.

The thermostat seems to be attached to the cylinder the same as always. I pushed the temperature up to 80 to see if that kick-started anything but it doesn't seem to have.

I also checked the feed and expansion tank in the loft and that looks fine.

 

[FiremanT]

in your pic the small grey box is your HW thermostat, to the right you will see the pipe coming out of the top of the HW coil, it has a T and a short section of pipe pointing up, that is the bleed point for your HW switch everything off and crack that bleed point until there is only water comes out, then turn everything back on again and see if that sorts it

Unfortunately when I screw it back on with the pliers as tight as I can it still leaks. I didn't remove the cap so I doubt it's cross-threaded. I have a grip wrench but I don't know if applying more force would be a good idea.

.

Tough Luck, Ian. You do realise that this is the cyber equivalebt to "it was okay until you touched it!!!" ?

 

[undertrained]

Two problems now.

I opened the small valve with pliers (though forgot to switch everything off) and bled it. Unfortunately when I screw it back on with the pliers as tight as I can it still leaks. I didn't remove the cap so I doubt it's cross-threaded. I have a grip wrench but I don't know if applying more force would be a good idea.

If it’s as tight as it will go, then unless you can replace it, you may need a plumber/heating engineer in. As for the hot water , try it with the heating on, it could be a stuck paddle/ball, burnt out microswitch or burnt out motor.

 

[dannynolan]

Thanks for your reply.

I have contacted my usual plumber but he won't be here til next week and I wouldn't mind getting the leak sorted.

I would like to get the little valve cap off to see if there's a rubber washer that's displaced, or failing that, get a new one, but I have to drain down the hot water system first as I can't see that there is an isolation tap.

1. How do I drain down the hot water system? Tie up the ball valve in the F&E tank then what.

2. Also to get a replacement valve cap thing - what is it actually called?

Thanks in advance.