Three days ago a power flush of the central heating system in my house was done by one of the engineers of a well known medium size plumbing business in London, C Anderson & Sons.

He spent over 4 hours to do the job and used a big machine connected to the pipes of a radiator that was disassembled. My system has 23 radiators and two boilers over four floors.

Yesterday, I had the Vokera boiler engineer come to fix one of the boilers. When a water pressure valve was changed a good amount of water from the central heating system was released.

The problem is that that water was very black. As black as it was before the power flush. I have kept a jar with it.

The Vokera engineer said that, in his opinion, that water should be much clearer right after the power flush and that it does not seem to have been done properly.

Is it normal that water is so dirty right after a power flush?

The heating in my house has been working reasonably well, but I have had a few problems with control valves over the years and, recently, major problems with the boilers. Perhaps due to the dirty water. I do want to avoid the risk of further problems caused by dirty water.

Thanks,

Antonio

In article ,
asalcedo writes:

Three days ago a power flush of the central heating system in my house
was done by one of the engineers of a well known medium size plumbing
business in London, C Anderson & Sons.

He spent over 4 hours to do the job and used a big machine connected to
the pipes of a radiator that was disassembled. My system has 23
radiators and two boilers over four floors.

Yesterday, I had the Vokera boiler engineer come to fix one of the
boilers. When a water pressure valve was changed a good amount of water
from the central heating system was released.

The problem is that that water was very black. As black as it was
before the power flush. I have kept a jar with it.

The Vokera engineer said that, in his opinion, that water should be
much clearer right after the power flush and that it does not seem to
have been done properly.

Is it normal that water is so dirty right after a power flush?

No, it wasn't done properly. You have cast iron (or rusted iron;-)
evidence and you can add that the boiler engineer said it wasn't done
right. Personally I wouldn't bother with a power flush, but since
you already paid for one, I would get them back to do it properly.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

They are going to fit new boilers and do the power flush again.

I have now researched further this matter. There seems to be an industry standard for TDS (Total disolved solids) and pH after a power flush. What are these values?

They are going to fit new boilers and do the power flush again.

I have now researched further this matter. There seems to be an industry standard for TDS (Total disolved solids) and pH after a power flush. What are these values?