"Balance Rad"

[Orroroo]

Sorry about this but I cannot seem to find an answer anywhere - what is meant by the term "a balance rad"? which I have seen used bur not explained. It seems to be a radiator on the system with no TRV on it but for what purpose?

Secondly, should you try to include it in balancing or should the flow & return be both fully open?

 

[Notch7]

Usually the only radiator with no TRV is the one in the room with the thermostat.

That radiator can still be balanced on the lock shield, but fully open on TRV side (flow side)

 

[oldbuffer]

1. The purpose is to allow some flow if all other radiators have TRVs and all are closed. Otherwise the pump is pumping against a sealed system and may be damaged. Its not really a balance radiator, it is a bypass radiator. Should not be necessary on modern systems which have, or can have, an automatic bypass valve fitted. This valve is connected between flow and return and will open when pressure exceeds a certain value.
2. As Notch7 says, can be, and indeed should be, balanced with the rest of the system.

 

[Orroroo]

Thanks, that's great.
More questions to follow on different subjects though i'm afraid.

 

[Madrab]

"a balance rad"

To be honest, there isn't such a thing as a 'balance' rad TBF.

There is a balanced rad, which is a rad that has been tuned along with the other rads to ensure the system heats up efficiently, the rad itself is at peak efficiency for heat transfer into the room and therefore allows a condensing boiler to be as efficient as it can be.

If you mean a bypass rad then that is something completely different. That is a rad that has standard wheel head valves, is usually in the same space as a wall mounted thermostat and it is designed to stay on when the other valves in the system shut down, this is to ensure minimum flow through the boiler on over-run and ensures the pump doesn't run against a closed system.

 

[Orroroo]

Hmm, OK
The plumber who sorted the system out back in 2001 put a small double rad in the newly created downstairs shower room without a TRV
It’s about 6 foot from the boiler so its roasting in there most of the time but freezing when the boiler goes off on the thermostat.
I was wondering if it was short circuiting the loop.

 

[jurassic sparkk]

Sounds normal its probably the most closest rad to the boiler.