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Draining Down System

So you are working on the heating and need to drain it down, but how? Here it is made easy by following these simple steps.

Drainig down:


  • Isolate at boiler controls (boiler spur switch).


  • Locate and turn off coldfeed, this is on pipe work coming down from tank above/in loft to pipework in cylinder cupboard.


  • Attach hose pipe to drain off cock with a jubilee clip on heating system, usually a radiator, and open the cock to start draining. Also make sure your draining into an outside grid.


  • When the water starts to slow down open the radiator bleed vents slightly so air can be dragged in to aid draining.


Job Done!



  • When its time to open the radiator bleed valves make sure its sucking in and not leaking out water, if this is the case just wait a bit longer.

  • You only need to open the radiator bleed vents on the upstairs radiators and the one your draning from.

  • If it is taking a very long time to drain the isolation valve on the coldfeed may be passing. So you will have to replace this valve.

Related topics


Faulty drain off valve.

Passing isolation valve.

radiator bleed key
gate valve
jubilee clip
Go Repairs
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