CH Update (Longish)

[Charles Middleton]

All,

Ive finally got around to looking into the problems posted with my CH system sometime ago on this thread ...

so I thought Id post an update for those interested.

I opened the bleed valve on the radiator that always needs bleeding (main bedroom) and set alight to the gas coming out. It did burn with a small blue flame.

Popped down to Wickes and purchased some corrosion inhibitor. Turned off the mains water supply. Drained the system down from the lowest radiator. Put the inhibitor in the tank and put the mains water back on.

Went around and bled all radiators then put the system back on. Now only one radiator in the house getting warm. Thought I may have incurred an air lock somewhere so dragged some water through various radiators using the drain valve to try and pull water through.

This didnt work. Problem eventually solved by turning on the raditators one at a time and forcing the water supply through them and bleeding to remove air. Now all radiators getting hot.

I have also turned down the pump speed as I think the system is drawing in air as well. So far so good. The system ran most of last night and I havent needed to bleed any air out of the main bedroom radiator. The house is also warm enough with the pump speed on low.

I'll keep an eye on it over the next month or so and test any gas I get out of the system.

Cheers,

CM.

[Charles Middleton]

Looks like I spoke too soon. Turned system on this morning to find only

2 radiators getting hot. Also boiler shutting down before thermostat temp. reached which must mean the water is getting too hot - probably as its only going through 2 rad's. So I have had to go around shutting off rads individually and reopened them to get the water flowing through. Is this just an air lock that hasnt worked its way out yet? What a weekend - forgot to mention that when i turned off the mains water yesterday I forgot to re-prime the electric shower and now the pump on thats making a nice noise as well!!! CM.

[mike ring]

"Charles Middleton" wrote in news: [e-mail]:

It may well be - I have to restart my system bit by bit after refilling.

I've got several loops

kitchen - 1 rad: bathroom 1 rad;

2 front rooms 2rads,

the other side of t'hovel, 3 rads.

I open one loop at a time, pretty much in the above order, and blast and bleed them one at a time.

With more than one rad on a loop, I may do one rad at a time.

(I've found it saves time in the end)

mike

[compo]

The message from "Charles Middleton" contains these words:

You and me both! I have ALMOST EXACTLY the same problem. In my case I needed to replace a pipe and clean out some accumulated sludge. The system worked better before cleaning than it does now! I have a couple of upstairs radiators getting hot and shutting down the boiler. Turning those off seems to push air along to other rads that can then be bled and thence get hotter. Each time I do this the downstairs begin to warm up and then just go cold again :-(

This morning I tried forcing water up through the donstirs manifold. This moved a lot of air but has not fixed the problem.

If I find the solution I will mail it to you. Meanwhile if you find the solution please email to [e-mail]

[compo]

The message from "Charles Middleton" contains these words:

Mike R> I open one loop at a time, pretty much in the above order, and blast and

Apart from the obvious spelling mistakes the above turned out to be the solution to my problem after all. In desperation I reconnected the hose to the downstairs manifolds and, with all downstairs rads open and upstairs (which were operating after a fashion) closed, forced water up through the system (both sides in turn) until it escaped through the header tank overflow. This appears to have moved my airlock around and immediately masses of air appeared in two of the radiators. After repeated bleeding the system appears to be getting back to normal. I am currently opening each of the upstairs rads in turn and bleeding the air from them.

[Charles Middleton]

Thanks for the update.

My system is still playing up. The only way I can get all radiators to now work is to close them all and then open then one by one. However, whilst doing this I am bleeding each radiator and NO air is coming out

- I havent a clue where this airlock is. I have also advanced the pump speed from 1 up to 2 in an effort to apply more pressure to the system and force the air around to *somewhere*. Im stabbing in the dark to be honest so any suggestions are more than welcome.

CM.

[mike ring]

"Charles Middleton" wrote in news: [e-mail]:

Have you got a noticeable high poin it your piping, or maybe more than one.

You may need bleed points there; you can get manual, (cheap) or automatic (dear, and may be unreliable)

There are other possible places for an airlock, like in the motorised valve area - look for any highish loops in your piping.

HTH

mike

[Bob Eager]

A suggestion I saw on here a couple of weeks ago, which worked for me just before Christmas....

Close off all but one radiator. Bleed a substantial amount of water (about a pint) from that one. Turn the system on and wind the pump up to maximum speed. Repeat in turn for other radiators. This finally fixed an airlock I'd been chasing for weeks.

[compo]

The message from "Charles Middleton" contains these words:

Errr....so is mine :-( I came home from work this evening to find the downstairs rads cold once again - ARGH! the system used to work so it should work again. I have drained the system again and started afresh, filling steadily. My main 22mm piping runs the entire length of the house under the floorboards and may be collecting air somewhere along that length. I am bleeding carefully and anxiously await heat.

To be continued.

[compo]

The message from compo contains these words:

Still bleeding and still getting some air out.