Adding leak sealer to towel radiator

[Zed110]

Hi everyone,

I have 500ml Fernox F4 that I want to add to my system. Having taken a look online it seems adding it to the bathroom towel radiator is a straightforward way of doing that. However, the videos I’ve seen online don’t seem to have the same set-up in terms of switching off the water supply to the radiator before draining enough out to then add in the liquid. Please see the photos attached to this message of my radiator. Is it simply a matter of turning the TRV to zero? Or do I need to do something else? The cap on the other side is stuck/glued in place. Do I need to remove this to then turn something off in there also?

Thank you in advance

 

[footprints]

You can just turn the thermostatic valve to zero for a short time, there will be a frost protection setting that will over ride the valve and open it if the room gets very cold but as long as the room is reasonably warm while you work no problem. The cap on the other end will come off, either unscrew or just twist and pull, wear a glove rubber or gripper to get a good hold on the smooth surface and protect your hand when it comes off suddenly! underneath will be a spindle to close the lockshield valve, count the number of turns to off and open the same amount when restoring the water supply to that side. A cloth soaked in hot water might help the cap to release.

 

[Zed110]

Hi footprints, thank you for the reply - thats exactly what I was after!

 

[Madrab]

Not an option to find the leak rather than using a sealer??

Leak sealer can sometime just mask the problem temporarily and then it returns. That and some boilers aren't the happiest when the system's filled with sealer due to the way it works.

 

[Zed110]

Had an engineer in recently for a boiler service (Grant Vortex Pro Combi 26E) and discussed the pressure loss. He checked what he could without finding a problem. I thought I'd try this before having to take up all floorboards, which I'd like to avoid.