draining the system. Radiators open or not?

23 Feb 2007
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United Kingdom
Hi after work on the boiler the CH sealed system was drained and needs re-filled. I turned off all the rads at both sides! before he drained it. He had trouble when re-filling it and is coming back today. If i closed the lockshield valves as well would that cause difficulty for him re-filling?

I.E. when refilling a system should the radiators be off but with the lockshield side open? or was turning all rad connections off before draining the right thing to do?

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i was more wondering whether it was right or not as to shutting them in the first place?

If you want to drain the system in order to say replace a part in the boiler should you close off all rads both sides to save emptyting all the water/inhibitor etc in the rads too?
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no its ok its just i did that because the guy was coming just to replace a small hose which was leaking in the CH pipework in the boiler, wife then told me when i got home he had trouble refilling said there seemed to be a blockage and is coming back today.

I wanted to ask if it was fair enough for me to do this.

I told my wife to tell him the radiators were all off but if his problems refilling were caused by the lockshield valves being shut is it not something he would check before refilling?
if he was told they where closed

"the rads are off"

coming from a customer is usually taken as the flow valves / trv's are closed


and if the flow valves where open refilling "should not be a prob

getting the rads to warm up would be ;)

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