radiator removal (trv rad) and new installation .

[steved101]

I am going to change a radiator for a designer type (ladder)

i have changed a radiator before but one with manual valves (wheelhead and lockshield). this one has a lockshield and a TRV.

do i just close the TRV to it's most off poition (lowest number) - will this stop water from entering it? i have heard before sometimes it does not fully stop the water flow .... and i don't want that to happen !!

also...

when installing the new radiator, do i just open the lockshield as much as i require until the new rad gets hot - or how do i make sure it is balanced correctly on installation.. i don't want the other rads to be less hot if that makes sense?

any help much obliged.

 

[D_Hailsham]

do i just close the TRV to it's most off poition (lowest number) - will this stop water from entering it? i have heard before sometimes it does not fully stop the water flow .... and i don't want that to happen

All depends on the make and model of TRV! Some close down completely at the lowest setting, others just have a frost setting. You should be able to find out what your valve does from the manufacturer's web site. If they just have a frost setting, you may be able to get a plastic "decorators cap" which replaces the head of the TRV and shuts the valve off completely. Honeywell sent me eight for free!

do i just open the lockshield as much as i require until the new rad gets hot - or how do i make sure it is balanced correctly on installation?

Set the lockshield to fully open and remove the head of the TRV when you let water into it. This will help prevent airlocks forming.

When you are sure that the radiator is working OK, leave the TRV top off, close the lockshield completely and then open a quarter of a turn. Check the inlet and outlet pipe temperatures (by feel or with a thermometer) and compare them to other rads. If the outlet is too hot, shut the lockshield a fraction and vice versa. Small changes can have a big effect - but it's not instantaneous; you will have to wait possibly 15 minutes for the change to be noticeable.