Adding Sentinel X100 concentrate.

What I would do is to turn off both valves then loosen one of the connections at the radiator side of the valve to drain out some of the (carpet staining) water - open the bleed valve to allow the water to run out - then re-tighten and inject the Sentinel into the bleed valve. However my radiators have a large bung in the top which has the bleed valve in it - I have a square key to remove the bung- then re-fit using PTFE tape.

If I ever fit a system of my dreams it will have a drain point to the outside of the house and a dosing point (whatever one is)

Sounds too complicated for me.

My system is new, it has a drain point in the passage and kitchen, you connect a hose pipe and away you go, the drain points are very close to doors leading to outside.

In case your wondering why the system does not have inhibitor, it actually did until my son opened the drain point and drained the system onto the carpet!

Yes. Close both valves to isolate the rad. Wickes do a small rubber pump kit

Easy peasy lemon squeezy.

You'll still need to drain down before adding concentrate - and rather further than if you use the highest rad in the house. In other words, drain about a bucket full out of a sealed system. Add the concentrate via the bleed valve on the highest rad. Then refill and with luck only that rad or it and the others on that level will need bleeding.

It really isn't that hard - do you have a towel rail in the bathroom?

If so, these are usually the easiest, especially if it is one with a bleed valve at the top, like this one here The rail

Now the valve will resemble something like this

It will only let a little out (as air cant get in yet) so when it stops, you need to undo the bleed screw at the top to let more out. (You don't need to take the bleed screw all the way out, just a half turn should do)

You need to let out a little more than thee amount of X100 you wish to add.

Once you have done this, you can, if it is the same as the one in the picture, undo the whole cap on the top, to reveal a large hole, ready for you to pour the X100 in with a steady hand, or a funnel.

Once this is done, screw the plug back on, and re-tighten the bleed screw. Now make sure the connection you undid at the bottom is fully tightened, and then turn on one of the valves.

Inspect for any leaks at the bottom!

Now unscrew the small bleed screw at the top a little, and let all the air out (until water starts to squire out) then tighten the bleed screw.

Now put the lock shield valve back to it's original position, and congratulate yourself of a job well done :-)

Toby...

I did something similar, except I drained from the drain point rather than unscrewing a radiator connector. One thing I over- estimated was the amount of water in a modern radiator. I drained it down a bit thinking I could pour in a litre through the removed blanking plug, and got less than half that in before the radiator was filled. Modern radiators have a rather small water volume (which makes good sense).

I take it that reply is directed at the OP?

Thanks to all, I bought Fernox Super concentrate, all I had to do was turn of the valves on the radiator, remove the bleed screw, insert the adapter, open wheel valve, pump in the inhibitor, close the wheel valve and close the vent screw. Re open valves to original positions.

Very easy and quick, the inhibitor comes in a silicon type tube and you use a silicon gun for pumping it in, the product comes with all adapters.

Although it may sound tedious, it wasn't bad at all.

Thanks to all, I bought Fernox Super concentrate, all I had to do was turn of the valves on the radiator, remove the bleed screw, insert the adapter, open wheel valve, pump in the inhibitor, close the wheel valve and close the vent screw. Re open valves to original positions.

Very easy and quick, the inhibitor comes in a silicon type tube and you use a silicon gun for pumping it in, the product comes with all adapters.

Although it may sound tedious, it wasn't bad at all.

Sounds a good product - but not sure how you managed to inject a quality of anything into a full radiator with the valves off - so there was nowhere for the displaced liquid to go.

Perhaps there was some air space.

No - to you.

Well in that case maybe it would have been helpful if you had explained why I should do it that way instead of using the "filling point" which seems a lot easier . And none of the radiators are "highest" . They are all on the same level as I live in a flat .

Have you actually tried it - and are familiar with other methods? It's just that saying you got 'the guy' to do such and such suggests not. As does plumbing in the drain point - it's not as though draining the system is an everyday requirement.

OK. But for most the biggest hassle when adding inhibitor is introducing air to the system which has to be bled out afterwards. And I can't see your idea minimising this.

I don't see what your problem is . It 's a lot simpler to use this than do it through the radiator . Draining the system may not be an everyday req't but I might as well make it easier when it does need to be done .

Bleeding radiators is a real problem is it ? I've never found it to be so.

Remembering where you left the key is the hard bit. I now have 5 - due to having to go and buy one because I couldn't remember where I put it /them.

A couple now live on the radiators which sometimes get a bit of air in them. One in the car for when I am at my daughter's and feel the top of the radiators and think "mmm, needs bleeding". I think the others are in my toolbox.

I know .I have two and I'm sure I left them somewhere safe so I could find them easily .So safe I now can't find them for love nor money . I'm going to buy a couple more next time I'm at Screwfix .Hanging them up next to the boiler seems the sensible option .

Sounds a good product - but not sure how you managed to inject a quality of anything into a full radiator with the valves off - so there was nowhere for the displaced liquid to go.

Perhaps there was some air space.

I was surprised, the instructions mentioned nothing about draining, you do have to replace the bleed cap quickly though, to prevent it spitting back out.

On Sun, 2 Nov 2008 16:59:23 -0000 someone who may be "John" wrote this:-

Something like

is harder to mislay.

At the moment I can't find the key which has the loop of string through it so that I don't lose it. However, I do have the "easy to lose" cheap key without the string. As I have been doing major surgery to the heating, just completed, this is somewhat annoying. I'm just cleaning the system out before adding inhibitor, so there is a fair amount of bleeding to do. When that is done a properly designed and installed system shouldn't require bleeding.

Sorry - not convinced. It's dead easy to add concentrate via the bleed screw. I'd guess you've never done it. Certainly no more difficult than having to remove a cap.

I like to look at the colour etc of the water that comes out.

Perhaps not in your flat. 14, on the other hand, is.