Draining CH system enough to fit a new radiator valve

Postby aerofive » Sun Oct 10, 2010 10:57 am


I need to fit a new radiator valve on an upstairs radiator. Obviously I've isolated the radiator (as I've taken it off) but my question is what do I need to do to get the water level down in the system to enable me to do the valve work?

I've got a Biasi 24S (or oen of its variants) combi boiler. Is it a case of finding the drain valve on the boiler or would I be better suited isolating all but one of the downstairs radiators and draining the required amount from there?

Any help much appreciated.

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Simply Build It

Postby htg engineer » Sun Oct 10, 2010 4:47 pm

Just changing the vale, you could connect a hose pipe to the radiator valve (as the radiator has already been removed) open the valve and allow to drain, open all upstairs radiator vents, this will drain enough for you to change the valve.

You will need to re-fill the system using the combi fill once valve is renewed. Remember to replenish inhibitor.

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