Radiator Cover - Powerflush

jb66

Hi all

I have Scottish Power Home Comfort,

One of my radiators wont heat up, i think the TRV is broken. I called out scottish power and they said my system needs a power flush as there is debris in the system, the water did look black when he tested it but its a 10 year old system. He said it should look like water.

Once the powerflush is done I have to call them back to check the TRV. He said he could change the TRV but it could break again. After he left Im starting to think its a cop out, maybe it wont break again, Id rather get it replaced and see rather than spend £400 on a powerflush,

Anyone else have experience of this?

System

You could just take the radiator off the wall. Remove the TRV head (this usually closes off the valve) and close off the other valve and you should only need to drain the one radiator. Wash it out with a hose pipe and put it back and see what has changed.

The more sophisticated way is to use an IR camera to see whether there is any flow.

PS. Have you taken off the TRV head and checked that the pin is free to move up and down. If it is stuck DO NOT welly it with a hammer. Use a piece of wood to press on it. It should move down under pressure and up of its own accord.

molerat

Is a power flush free with your cover, of course not. It is the magical answer to all CH ills (and a nice little earner). Get the head off and exercise the pin, I have to do it every autumn after the rads have been off all summer. Takes me half an hour to go round the whole house.

icharus

Before anyone can arrive at a diagnosis on how bunged up your system is they should first check on how all your radiators are performing in terms of heating from top to bottom. Turn your thermostat up to about 25 C so that your system is full on, then test how evenly your radiators are heated from top to bottom. If some are cooler towards the bottom then your system is probably getting bunged up. If not, then simply have the valve replaced after first following the advice of Hengus and Molerat.

You should also bear in mind that your system is now 10 years old. This is the average lifespan of a ch system, it will be showing it's age. At this age I would personally only keep it going through minimum intervention. If it isn't broke don't fix it! Save the cost of the power flush for new pipes and radiators, hopefully a few more years down the road. A power flush at this age can open up a can of worms. If it isn't too bunged up a cheaper option is to run it through via a simple mains flush and then dose it with the appropriate amount of inhibitor.

As Molerat says power flushing is now an industry and a good earner. Incidentally £400 is cheap for a power flush. They usually try to rip you off far more than that!

bertiewhite

To echo Molerat & Hengus's comments - I had to "exercise" my TCV pins as well last autumn. There are videos on YouTube how to do it. Even if you do decide to replace a TCV, it's easy to do and you can get them for a tenner.

If you really don't want to take the radiator off the wall, how about running 2 lengths of hosepipe to the radiator and flushing it through that way?

System

icharus wrote: »

Before anyone can arrive at a diagnosis on how bunged up your system is they should first check on how all your radiators are performing in terms of heating from top to bottom. Turn your thermostat up to about 25 C so that your system is full on, then test how evenly your radiators are heated from top to bottom. If some are cooler towards the bottom then your system is probably getting bunged up. If not, then simply have the valve replaced after first following the advice of Hengus and Molerat.

You should also bear in mind that your system is now 10 years old. This is the average lifespan of a ch system, it will be showing it's age. At this age I would personally only keep it going through minimum intervention. If it isn't broke don't fix it! Save the cost of the power flush for new pipes and radiators, hopefully a few more years down the road. A power flush at this age can open up a can of worms. If it isn't too bunged up a cheaper option is to run it through via a simple mains flush and then dose it with the appropriate amount of inhibitor.

As Molerat says power flushing is now an industry and a good earner. Incidentally £400 is cheap for a power flush. They usually try to rip you off far more than that!

I am not sure that I agree with you 100%. This is quite an informed article:

http://www.ianbgas.co.uk/Heating%20water%20quality.pdf

I am currently looking at a replacement boiler and it is interesting to see how manufacturer's requirements are changing. For example, Atag are happy for sealed systems to fitted with softened water, and inhibitors are now the exception. No doubt based on the latest industry advice from Germany.

molerat

icharus wrote: »

You should also bear in mind that your system is now 10 years old. This is the average lifespan of a ch system, it will be showing it's age.

My system is geriatric then, 33 years old and still going strong.

My son was told by BG that a powerflush was needed to try and get his system back to working properly and that might not work so it would be a new boiler. £80 worth of bits including chemicals and some parts that were changed because they were looking tatty system is up and running fine. Of course changing the boiler would have solved the problem as the £25 faulty part would have been replaced.

icharus

I know that German boiler manufacturers, my own included, state that the addition of inhibitor will invalidate the warranty. I believe this to be a bit of a cop out in respect of British c.h. systems, because we have a universally different c.h. system from the Germans, where they take steps to keep O2 out of the system. The German manufacturers should be clearer on this requirement in their advertising and at the point of sale.

I believe that very few British c.h. installers would install systems (including German boilers) and not add inhibitor.

I believe that there is also a problem with plastic pipework in the newer installations. Despite allegedly being impervious to o2 I don't believe this to be the case. I have direct experience of this in two different installations. I won't list the methods, but there is also bad practice in the industry where oxygenated water is repeatedly allowed into the system.

Personally I would feel insecure without an inhibited system, unless additional equipment was installed in line with German methodology. Post installation this can be expensive particularly if there is restricted space.

Interesting article. He still has the benefit of an old (more than 10 years) cast iron heat exchanger!

icharus

molerat wrote: »

My system is geriatric then, 33 years old and still going strong.

Built in obsolescence in the new systems, but much more efficient!