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Hi all, bit long winded but please stick with me.
Was called to a property where 3 or 4 radiators are not getting any heat at all. I did all the usual tricks of opening all valves, closing working rads etc until we finally got a little heat into some of the non performers. Then I thought brilliant just needs balancing.
Went out to garage to put heating on constant to begin balancing and noted that the boiler is only an 18kw Worcester heat only.
I did sort of a reverse calculation and worked out that to warm the existingrads and hot water (150L Unvented) will take approx 24kw.
I fed this back to the LL as I didn’t want him to be ripped off as it was BG that did the install and would imagine he’d have some recourse even a couple of years down the line. He got a BG assessor out (you know the sort that have been installers for 20 odd years and think they know it all) and he said that I’m wrong and based on his heat loss calc the requirement is 18.22kw. I know!!! Already over the boilers capability!! He said that it can’t be wrong as when BG put it in they would have run 28mm primaries to the airing cupboard to deal with the heating load and as there are only 22mm pipes there currently putting a larger boiler in would have no impact on the total output.
He has said that TRVs are to blame and has recommended that Drayton TRV4s are fitted throughout to prevent the problem reoccurring in the future.
I have never come across this scenario where I have had to work backwards and want to make sure that I’m not doing something glaringly wrong but the heating requirement is 13 rads (4 big doubles) of various sizes but only a couple I would say are small as well as 4 big towel warmers and the unvented cylinder.
Surely the fact that the BG guy already says the requirement is 18.22kw says that the boiler isn’t up to it?
Thanks so much if you’ve read this far.
Any thoughts
Was called to a property where 3 or 4 radiators are not getting any heat at all. I did all the usual tricks of opening all valves, closing working rads etc until we finally got a little heat into some of the non performers. Then I thought brilliant just needs balancing.
Went out to garage to put heating on constant to begin balancing and noted that the boiler is only an 18kw Worcester heat only.
I did sort of a reverse calculation and worked out that to warm the existingrads and hot water (150L Unvented) will take approx 24kw.
I fed this back to the LL as I didn’t want him to be ripped off as it was BG that did the install and would imagine he’d have some recourse even a couple of years down the line. He got a BG assessor out (you know the sort that have been installers for 20 odd years and think they know it all) and he said that I’m wrong and based on his heat loss calc the requirement is 18.22kw. I know!!! Already over the boilers capability!! He said that it can’t be wrong as when BG put it in they would have run 28mm primaries to the airing cupboard to deal with the heating load and as there are only 22mm pipes there currently putting a larger boiler in would have no impact on the total output.
He has said that TRVs are to blame and has recommended that Drayton TRV4s are fitted throughout to prevent the problem reoccurring in the future.
I have never come across this scenario where I have had to work backwards and want to make sure that I’m not doing something glaringly wrong but the heating requirement is 13 rads (4 big doubles) of various sizes but only a couple I would say are small as well as 4 big towel warmers and the unvented cylinder.
Surely the fact that the BG guy already says the requirement is 18.22kw says that the boiler isn’t up to it?
Thanks so much if you’ve read this far.
Any thoughts
