Central heating system

[jasyk34]

Hi

In my parents house the hot water cylinder water was heated wherever the heat was on in the house but has stopped working. The heat still works but no hot water in cylinder. They are able to use the immersion heater to heat the water. Anyone suggest what the problem might be. Had a plumber out and he thought it may have been the diverter valve but couldn't find it !

This is the setup to the hot water tank and have no idea what's going on here. Maybe the picture might help.

There are 2 vertical 15mm pipes out of shot in the attached picture. With the heating on, the left vertical 15mm pipe is very warm and there is a pipe tee coming off it to the bottom of the hot water cylinder as seen in the picture. The right hand vertical 15mm pipe is cold and there is a t off it going to the hut water cylinder with a TRV between it and the tank. The bottom 15mm warm pipe then has a t to the pipe with the TRV.

There is 28mm pipe into the top of the cylinder that feels warm to the touch. Lastly a 28mm pipe at the bottom of the tank that I think comes from the header tank in the loft.

 

[Harry Bloomfield]

This is the setup to the hot water tank and have no idea what's going on here. Maybe the picture might help.

It looks like they have a TRV, feeding the cylinder heating coil - but why would that be???

Perhaps the TRV has stuck closed? If you remove the TRV head, it just unscrews by hand, via the chrome ring, below it should be a pin stuck up. In the sprung up position it allows water through, in the pressed down position (by the head), it is closed. The pin only moves a couple of mm. check it is up, by pressing it down with the side of a pair of pliers. If will not go down, then it is stuck down - try pulling it up gently with the pliers, to free it. Careful, they are easy to pull right out.

 

[jasyk34]

Thanks. Will give that a try. Not sure why it would have stuck closed. It had never been touched and it's at max ( fully opened)