Best chemical flush?

[sammathias]

X800 for more than 1 hour that's for sure. 24, hours even better. Then hot flush it. Open vented??

 

[Deleted member 96286]

I used the X800 and it worked a treat.

I fully opened all lockshields and TRV's in the house (3 floors), drained down the system via a rad in the basement and using the fill valve on the boiler, flushed it through with fresh water on each level.

I added the X800 to a rad after removing an air valve, via a filling loop I made up a while back, filled up the system and bled out all the air on all three floors. The instructions say to fire up the boiler and circulate the X800 at working temperature for an hour, so this is what I did.

After about 40 minutes, two of the rads that hadn't been heating up for years, were red hot, as was the entire system.

After an hour, I attached my hose to the basement rad and cracked open the valve. What came out looked like jet black treacle, years of sludge and metal deposits came pouring out. I thoroughly flushed out the X800 and the years of crap it dislodged until the water ran clear.

I refilled the system, added inhibitor, bled every rad and turned on the heating. Every rad in that house is red hot now. I balanced the system throughout the house and both me and the homeowner are very happy at the result.

The chemistry is NOT a cure. It will add life to an ancient 8mm microbore system, until money is available for a repipe. A Magnaclean is now being fitted too.

I'll now offer this to customers who want rads added to their existing systems, as it does dislodge crap that fresh water flushing does not, and it does the business in about an hour.

It's no miracle cure, and won't work on every system, but for 20 quid, it's certainly an option and worth a go.

 

[Best]

Glad you achieved a big improvement.
I used to just flush systems many years ago by using mains from a garden hose, often removing every rad and also flushing the pipes. It also achieved great results. I think still good to do this as a first clean.
I have found the Fernox F5 good for removing magnetite. The clean looking water in a system will turn grey and a mag filter would pick it all up.
Nothing beats removing microbore pipes and also scrapping old rads imo.

 

[AWheating]

Acid would be best. X800 only works for a short time as it's designed for quick powerflush use. After a day in a system it is doing nothing more. Others last longer but are not as strong.

Calmag do a product similar to fx2 it's only £5 a bottle. Works quite well.

 

[Harvest Fields]

Acid cannot be used on aluminium

 

[Deleted member 96286]

Acid would be best. X800 only works for a short time as it's designed for quick powerflush use. After a day in a system it is doing nothing more. Others last longer but are not as strong.

Calmag do a product similar to fx2 it's only £5 a bottle. Works quite well.

X800 is the fast acting version and can't be left any longer in the system than an hour before being flushed out.

 

[ShaunCorbs]

X800 is the fast acting version and can't be left any longer in the system than an hour before being flushed out.

Can be left in upto a week

 

[Deleted member 96286]

Can be left in upto a week

It's designed to be fast acting and work in only an hour. If you left it in the system for a week, the X800 would not harm the system itself, but all the sludge, rust and debris it has dislodged would get circulated around the system which is not good, and there would be no benefits.

According to Sentinel customer service, here's their recommendations:

Hi there, Sentinel X800 is designed to be flushed out within 1 hour. If you wish to leave the cleaner is for longer we would recommend using the Sentinel X400, this can be left in the system for upto 3 weeks.
Kind regards
Customer Service

 

[Harvest Fields]

Can be left in upto a week

Not as far as I was told

 

[ShaunCorbs]

Not as far as I was told

It's on the bottle