Blocked central heating

[VSR]

Dear all,

a lot of radiators in my home appear to have been blocked with sediment and remain cool. Would using a cleaner such as Fernox unblock them or do i have to disconnet the radiators and flush each of them? Powerflush is not an option for me as two companies gave quotes that are simply out of my reach.

many thanks
VSR

 

[Steve69the69Gas]

Hi,

Yep drain down and flush each one out, check pump also.

 

[gas4you]

You do have choices.

1) Drain a small amount of water out of your system, then add Sentinel X400 sludge remover (other good makes are available ), leave in your system for UP TO 4 weeks, using it as normal, then drain and flush through system wth clean water.

2) The same as the above, but use X800 (other good makes are available ), but only leave this in for approx 1-2 hours.

3) Drain down, remove each radiator in turn, take them outside and flush with a garden hose, but this will not clean the pipes.

If you have a combi or sealed system I would do 1 or 2 above, if not I would do 1 or 2 above, then 3.

If it is an open vent system, don't forget to clean the F & E tank thoroughly before re-filling the system and adding X100 to the final re-filling.

 

[JPC]

ignore dave and steve, i'll come and powerflush for £500 including travel time from leicester

 

[Agile]

X400 needs at least FOUR weeks !

X800 is best left in for a minimum of six hours and overnight is easier.

In both cases the heating system should be on for much of the time although its adequate if its just being circulated at a minimum temperature.

If badly sludged then remove and flush out all those which are cold at the bottom and then use X800.

Tony

 

[gas4you]

X400 needs at least FOUR weeks !

Official info I've beenn given from Sentinel states it breaks down and stops working at around 4 weeks

X800 is best left in for a minimum of six hours and overnight is easier.

Not if the boiler has an aluminimum HE. Maximum of 3 hours is allowed. Hence, as we do not know what boiler OP has, the time span stated in my post.

 

[Agile]

Official info I've beenn given from Sentinel states it breaks down and stops working at around 4 weeks

Not if the boiler has an aluminimum HE. Maximum of 3 hours is allowed. Hence, as we do not know what boiler OP has, the time span stated in my post.

Sounds just like an Ideal boiler!

I have heard a lot of nonsence like that from people who work for Sentinel too.

At a show the poor salesman on their stand was trotting out their X400 for two to three weeks and the guy standing in front of me said 4-5 weeks was needed for optimum results.

I was pleased to vocally agree with him! Thats my experience over many years of using X400. I trust my experience rather than sales talk otherwise we would all be fitting Ideal boilers!

X800 is also better given about six hours or a bit more. Thats right about their recommendation that its only used for three hours when the boiler has an aluminium heat exchanger. Thats an Ideal boiler again!

For the remainder with a cast iron, copper or best of all a stainless steel heat exchanger I still recommend at least six hours when being circulated by the system pump. Of course with a power flusher pump a couple of hours is enough.

Tony

 

[Soggy_weetabix]

I would use Fernox DS40, following the instructions given by Fernox.

Quite aggresive stuff though!

Dave

 

[VSR]

many many thanks to all those who kindly posted replies. since some (or all of you) appear to be engineers, would you please clarify something for me?

my radiators are on a feed&return system. should a radiator be completely blocked, will the cleaning solution still somehow diffuse into it?

the boiler is a Hamworthy Purewell 60KW with a cast iron HE. anything special about this?

the radiators are 35 in number, spread on four floors.i am tempted to take up the offer from of the gentleman from liecester.

many thanks, once again
SRV

 

[Agile]

Turn off all the hot rads when you first add the inhibitor so that the flow is concentrated into the bad ones. If most are blocked then you will need 2-3 litres of chemical

There is nothing special about the boiler apart from being very inefficient.

It would give very good return on capital to replace it with a modern efficient unit.

Power flushing requires each rad to be flushed in each direction several times. That usually takes 20-30 minutes each to do properly.

Anyone from Leicester will need an overnight in a hotel.

Tony

 

[VSR]

tony, thanks
which chemical would you use exactly and where can i buy it?

 

[sooey]

the radiators are 35 in number, spread on four floors.i am tempted to take up the offer from of the gentleman from liecester.

I think his price has just gone up.

 

[Agile]

I would use citric acid but I dont advise that for your use.

I would suggest X800 in the system for eight hours with the first four just in the bad rads and then opening the others if and when the flow improved. Start with the CH temp low and then increast it to maximum over about an hour or two.

To use it to the best advantage requires considerable skill and experience.

But the chemical is only about £16 per litre and three litres is probably adequate.

Tony

 

[VSR]

the radiators are 35 in number, spread on four floors.i am tempted to take up the offer from of the gentleman from liecester.

I think his price has just gone up.

true. that is a problem. i do not have a problem paying more for a bigger job. quotes are often inflated also because some tradesmen assume you are loaded to live in a large house. not always true though.

 

[wiggikins]

ignore dave and steve, i'll come and powerflush for £500 including travel time from leicester

SCAB