Understairs WC radiator too hot

Weyhey

We have gas central heating and a small radiator in our understairs toilet with a value that has an arrow on it. The radiator is either very hot or off, there is no inbetween no matter how little you turn the valve and as such in winter the room is either way too hot or too cold.

When getting house renovated and replumbed I wanted a TRV on the radiator but the builder said something about it not really being possible. I think he might have even given a reason about the rad being one of the first or last on the system.

Is there anything I can do to get variable or thermostatic settings on this radiator or any radiator in this room?

TheW1zard

Have you any radiators that don't heat up fully?

Weyhey

TheW1zard wrote: »

Have you any radiators that don't heat up fully?

Not sure as we rarely put rads on high due to smell and hissing sound of some of them and also because normally the house heats up quite quickly.
Kitchen radiators are steel vertical rads which take a while to heat up and cool down but rarely have these on high anyway.

I can put all rads on high for an hour or so and test this?

TheW1zard

You should balance your system.

Basically the radiator nearest your boiler on the start of the run should be open just a little bit, because it has the most pressure, and hottest water nearest it.
The radiator at the end of the run, upstairs and furthest away should and needs to be fully open. Radiators gradually being more and more open as you get further from the boiler.
This is the most efficient way they will all heat up properly.

You should also bleed all the radiotors and release any air in the top of them. Again doing this from the 1st on the system to the last, chasing the air down and out of the system.

Start by bleeding them. Close all of them, and work around 1 by 1 from the 1st to the last opening them fully. Bleed.

Then balance, all of them will be fully open now. Go around and starting from the 1st. 1st just open, and the rest gradually opening more and more. Last full open.

Sorry about the lengthy waffle!

Weyhey

TheW1zard wrote: »

You should balance your system.

Basically the radiator nearest your boiler on the start of the run should be open just a little bit, because it has the most pressure, and hottest water nearest it.
The radiator at the end of the run, upstairs and furthest away should and needs to be fully open. Radiators gradually being more and more open as you get further from the boiler.
This is the most efficient way they will all heat up properly.

You should also bleed all the radiotors and release any air in the top of them. Again doing this from the 1st on the system to the last, chasing the air down and out of the system.

Start by bleeding them. Close all of them, and work around 1 by 1 from the 1st to the last opening them fully. Bleed.

Then balance, all of them will be fully open now. Go around and starting from the 1st. 1st just open, and the rest gradually opening more and more. Last full open.

Sorry about the lengthy waffle!

Not waffle at all. Thank you so much for your time TheW1zard I really appreciate it and will look balancing the system.

Are radiators positions logical i.e. could the downstairs wc rad really be the first rad on the system even though a different rad could be between that and the boiler?
There is a radiator in the utility room where the boiler is and two rads in the kitchen before going out to the hall where the understairs WC rad is yet I think I remember the builder saying the WC rad was the first or last in the system so couldn't have a TRV fitted.

Is there a way of knowing which rad upstairs might be the last when two bedrooms (one containing the hot water cylinder) is within equal distance of downstairs utility/boiler room.

TheW1zard

Yes they are logical.
Im not an expert but the bottom floor radiators heat up first and through convection the hot water rises to the top.
Try follow the pipes around and see if you can figure it out. The one nearest the boiler is 1st so your scenario seems strange without seeing it.

Id go around bleeding all the radiators anyway, turning them all fully open.

A quick way to figure out which ones 1st is to close all of them and open which you may think is logically 1st. If it gets hot it is.
Logically the one in the utilty room is 1st id say