DIY Doctor

No pressure in rads...

Postby notgnirraw » Mon Nov 02, 2009 6:57 pm

Dont know much about heating.... have just had the system flushed properly and all was fine. Now I dont have heat upstairs. I have tried to close all downstairs rads to see if that forces pressure up. I am getting slight heat in the 1st rad but nothing else. I have then bled all rads. Lots and lots of air in the upstairs rads but now it wont release. I.e. still air in them but even with bleed valve removed I get no water??

Any ideas?
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Simply Build It

Postby rosebery » Mon Nov 02, 2009 9:40 pm

What does "just" mean. In last few days / weeks / months? There may be a case for getting the guy back who did it to sort this problem out for you at no cost to you.

Combi boiler? If so system not repressurised OR you are losing pressure due to a leak. Look at your combi. There will be a pressure guage. If its reading less than 1.5 bar then you need to top up the pressure.

You will either have a built in filling loop controlled by a special key that fits in the base of the boiler or an external loop. If the latter you can identify it as a length of braided flexible ipie one end (inevitably) connect to the boiler and the other to a ballofix service valve. Shut all bleed vents you have opened and opetrate the filling the valve. When the pressure reaches 1.5 bar shut the valve and go round in turn opening up the bleed valves so the rads fill with water. You will need to keep topping up the pressure from time to time until all rads are filled and the pressure is steady at iro 1.5 bar.

The run the system and monitor the pressure reading. Make sure the filliling loop valve is completely shut when you have finished or you wil overpressurise the system.


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