Bypass radiator

[bhm1712]

actually regs state that all living spaces require TRV's so bathrooms and kitchens do not require one if you read between the lines

it does not make any difference what Plan i have!!!!! the simple fact remains if somebody was to turn off all the rads manually, the pump would be pumping to a dead end. the assumption that all the valves are stiff is ridiculous on your behalf, all the control valves on my rads are very easy to turn. i could go around the house in 3 mins and turn every single rad off from the system whilst the pump was still running.


instead of trying to help ,you come on here laying the law down of what should be and what shouldnt be, but at the end of the day things are not always done by the book. Im not a plumber and maybe you are, your simply not grasping what im asking about at all

The regs say that all rads should have TRVs, except the room with the room sat.

The reason is not for a by-pass, but to prevent the rads in that room shutting down before the controlling stat

you insult my intelligence, i never said that i thought TRV's where for a bypass.

so mr DO IT ALL please tell me what safety device should be fitted on a heating circuit that does not have a bypass and that it IS possible to turn off all the rads with the control wheel.?

 

[mogget]

if somebody was to turn off all the rads manually, the pump would be pumping to a dead end.

This is theoretically possible. It's also theoretically possible to drive a car into the sea, but you don't do it!

If a child were able to go around closing all the radiators, I would question whether that child was adequately supervised.

Also if there was insufficient flow the boiler stat would come into operation and shut off the heat.

I think you are overthinking this problem.

If you want peace of mind you could fit the radiator nearest the room stat with two lockshield valves and balance it along with the others.

 

[bhm1712]

i am planning to fit TRV's in the bedrooms only

i think you probably right, im overthinking. im just paranoid about possibilities!

 

[kevindgas]

what is the definition of a bypass radiator, and is it plumbed in differently than a usual rad? all i know is that it is there as a safeguard for the boiler so there is always a path of flow.

As far as I believe a bypass radiator is a radiator that is permanently open to the system

i have been reading that a bypass rad should be fully open either with 2 LSV or no valves at all.

no LSV at all, just direct plumbed

if thats the case how can you balance the system properly

you can't that's why it is no longer used as an option.

fit a bypass VALVE between flow & return pipes as far away from boiler as possible.

 

[D_Hailsham]

what is the definition of a bypass radiator, and is it plumbed in differently than a usual rad? all i know is that it is there as a safeguard for the boiler so there is always a path of flow.

Bypass radiators are required for solid fuel systems. This is because they do not shut down instantly, so there must be a permanently open circuit to dissipate the heat when "turned off". Gas and oil systems only need a bypass circuit if the boiler manufacturer says so.

is it possible that on a system with no auto bypass and no rad with 2 lockshields or no valves at all that one of them is still a bypass radiator?

Until you converted your system to C plan, the hot water cylinder would have acted as a bypass circuit.

i have been reading that a bypass rad should be fully open either with 2 LSV or no valves at all. if thats the case how can you balance the system properly?

You don't need a bypass rad!

The problem you raised, of nowhere for the water to go when all rad valves are closed rad, is solved by having an automatic bypass valve (ABV). But, if you have a radiator with two normal valves (i.e not a TRV) you may not need an ABV. This rad is balanced just like any other rad.

An LS valve is the same as a wheel valve; it just has a cover over it instead of the wheel. As it is accepted practice for the rad near the room thermostat to be fitted with 2 LS valves and not a TRV, this rad will form the bypass circuit.

If you have TRVs, an ABV is a good idea as it prevents the pressure getting too high in the rad circuit as the valves close down, which could cause noise.