Rads stopped working

marbar

there are some threads about cold rads, but none seem to relate exactly to my problem.
boiler is working (recently serviced) and up until a few weeks ago was heating water and rads, but now the rads are no longer heating up. only 5 rads in the apartment, but not even the pipes to them are warm.

thermostat is turned all teh way up. cylinder is boiling hot, but nothing from the rads

any ideas?

shane0007

Faulty motorised valve

marbar

so plumber with parts?
any recommendations for dun laoghaire rathdown?

shane0007

Check in your hot press for a box like valve on the pipes. There should be a slider that you can move from the auto position to the manual position.

marbar

this one?

Hogan1

Check if your zone valve is working

shane0007

Yes that's a Myson valve. There is a slider on one end. It needs to click onto manual catch to hold in the manual position.
Slider is on the bottom.
Do this & turn on the boiler to see if the rads heat.
If so, you can buy a replacement head for this valve & can be changed very easily, wires only, colour for colour.

marbar

there's a little safety to stop you moving it to manual, but if you get passed that the slider is on a spring and won't stay in manual

shane0007

marbar wrote: »

there's a little safety to stop you moving it to manual, but if you get passed that the slider is on a spring and won't stay in manual

It will click onto a holder. Slide to manual & pull into the grip. Slowly release to ensure to stays. They can be a bit finicky but it will hold.

marbar

aha! the safety also holds it into place when manual is selected. it's there now and holding, boiler is on full blast


so if that does the trick and heats the rads, i need to get a replacement head for the myson valve. is that correct?

appreciate your help here!

shane0007

Yes. It's a fairly simple job. Ensure electrical power is off & confirmed off. There is two flat head screws holding the valve to the base. Replace wires one at time. They are colour coded.
Valve head is about €45 + vat. Most plumbing suppliers will have it in stock.

marbar

legend

every rad is firing away. does it mean that the thermostat is no longer working as well? so heat wise, i'd have to turn the rads down so it's not on full blast?

thanks again. very much appreciated!

raymk111

by any chance are the rads full of air ?

shane0007

It will depend on what way it is wired. The MV might only be wired through a switch & the stat is wired through the boiler or it could be wired properly with full boiler interlock. Would not know without looking.
Change the valve & you are back to the way you were before valve became faulty.

marbar

thanks again
you've saved me alot of messing / worry

shane0007

You are very welcome

Cedrus

marbar wrote: »

legend

every rad is firing away. does it mean that the thermostat is no longer working as well? so heat wise, i'd have to turn the rads down so it's not on full blast?

As you have put the valve in manual, the zone thermostat will not do anything (doesn't mean it's not working) and neither will the zone timer (assuming of course that you have both of these) so you will have to turn it on and off at the valve until you replace the head.

You could also set the heating times the same as the cylinder zone, leave the heating valve in manual and let the water zone run the show until you get it sorted.

WhatNowForUs?

And when your doing up the repairs you might want to put a bit of insulation around the pipes.