I'm a newbie to the group and I have read the FAq on how to balance a heating system.
My question is should the inlet or outlet valve on a radiator be used as the LSV?
All of the radiators in the house we have had extended were without the caps described in the FAQ and all valves were fully open. This means that the radiator at the far end of the house, which I assume is last in the circuit, never gets more than luke warm.
Any help would be greatly appreciated.
Keith.
Given a free choice, I would use an LSV on the outlet - but it doesn't really matter.
All you are doing by partially closing the LSV is adding some artificial restriction to the flow through that rad, and it doesn't really matter where you put it.
It really doesn't matter - although on some it might make a slight difference to noise.
However, if you intend fitting TRVs at some point which *usually* go on the input, it might make sense to key down the output valves and retain these settings.
They should simply be fitted to the end of the rad which is most accessible for the user.
Although many modern ones are bi-directional (can be put on flow or return) there are still some around with an arrow indicating the flow direction that must be followed. Putting these on the wrong way end can cause water hammer and/or lead to premature failure of the valve. If you have a directional one that is the wrong way for the end you want to fit it, you can reverse this by having the control head horizontal instead of vertical, but it is not ideal for aesthetic reasons.
???
Phil The uk.d-i-y FAQ is at
I think you meant to say the LSV should be fitted to the end that is _less_ convenient so that the TRV (or other control valve) is at the _more_ convenient end?
As I read the post, the OP doesn't have TRVs, but simply two LSVs. Are these ever directional?
Exactly - well spotted.
Phil The uk.d-i-y FAQ is at
No! :-)
I put my comment in the wrong place - it was supposed to be under your's referring to the TRV's you mentioned.
The "???" was because I'm not sure what you mean by "key down the output valves and retain these settings."
Phil The uk.d-i-y FAQ is at
Some think that when you fit TRVs, there's no need to balance a system, so have the lockshield valve fully open. There's some truth in this in that all rads will probably get hot eventually, but it might be that the last in the chain does so very much later than the rest.
So my comment meant that if you use the LSV which is set correctly on a balanced system as the one you keep when fitting TRVs, you'll save some work.
I would not credit it with having *any* truth. Its just a bodged system which the TRVs *partially* (only partially) correct for. They might also suffer a reduced life because some of them will have to throttle the full pump pressure instead of the reduced pressure in a pressure equalised (balanced) system.
OK, got you. You could also swap the "already balanced" LSV to the other end if you want to put the TRV where the LSV is, or just count its turns and set the other end to that valve.
Phil The uk.d-i-y FAQ is at
Absolutely. I was just trying to give a small tip to minimise future work.
Yes. that's appreciated - I'm saving tips up for an update to the balancing FAQ. Any other suggestions for improving it, from anyone, are welcome.
Phil The uk.d-i-y FAQ is at
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