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Product Reviews

1Ltr. A powerful cleaning agent for central heating systems. Specially developed for use with power flushing equipment. Removes iron and calcium-based deposits to restore circulation and system efficiency. Effective hot or cold. No neutralisation procedure is needed.

1Ltr. A powerful cleaning agent for central heating systems. Specially developed for use with power flushing equipment. Removes iron and calcium-based deposits to restore circulation and system efficiency. Effective hot or cold. No neutralisation procedure is needed.
Average Customer Rating:
4.909 out of 5
4.9
 out of 
5
(11 Reviews) 11
Open Ratings Snapshot
Rating Snapshot (11 reviews)
5 stars
10
4 stars
1
3 stars
0
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1 star
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11 of 11(100%)reviewers would recommend this product.
Customer Reviews for Sentinel X800 Heavy Duty Sludge Remover 1Ltr
Review 1 for Sentinel X800 Heavy Duty Sludge Remover 1Ltr
Overall Rating: 
5 out of 5
5 out of 5
Value: 
4 out of 5
4 out of 5
Features: 
5 out of 5
5 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating: 
5 out of 5
5 out of 5
Value: 
4 out of 5
4 out of 5
Features: 
5 out of 5
5 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
5 out of 5
5 out of 5
Great Product
4 Apr 2014
By SlowerThanYou
, South East
"Was having problems with poor hot water output on our combi boiler - it would take a good couple of minutes after turning the taps on for the water to get fully hot, and after a further minute or two the boiler often shut down and the water ran cold again.
A bit of online research led me to suspect that the cause was likely to be a fairly common problem:- Sludge/magnetite in the CH system blocking the plate heat exchanger from transferring heat efficiently to the DHW.
In an attempt to avoid the ~£500 cost of a professional powerflush (plus the possibility of having to have the plate heat ex cleaned or replaced by an engineer) I thought I'd try putting a litre of this in the system in the hope it would flush enough crud out to get us back up and running. Worth a punt, I thought...
Well, it worked better than I could have hoped! Added the X800 via a radiator, ran the heating for a few hours to get it well circulated, then ran a hot tap for 10 minutes to ensure the plate heat exchanger got a good blast. The problems cleared up pretty much as soon as I'd done this, but I left the X800 in for a few days before flushing thoroughly and the boiler performance gradually improved further over this period.
After flushing, refilled the system and added inhibitor and it's been great since. Saved me the not inconsiderable cost of a powerflush, so am I pretty delighted!"
Review 2 for Sentinel X800 Heavy Duty Sludge Remover 1Ltr
Overall Rating: 
5 out of 5
5 out of 5
Value: 
5 out of 5
5 out of 5
Features: 
5 out of 5
5 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating: 
5 out of 5
5 out of 5
Value: 
5 out of 5
5 out of 5
Features: 
5 out of 5
5 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
5 out of 5
5 out of 5
What A Result...
14 Nov 2013
By Clansmen
, Glasgow
"Had probs with my Combi Boiler. Scottish Gas said I needed to fork out £620 for a power flush. Decided that I would try adding this first after reading others reviews before spending so much money.
Was amazed after one day noticed big difference. Left in running round system for two weeks then flushed out, now Scottish Gas say no need for power flush.
The cost of two cans as opposed to powerflush speaks volumes."
Review 3 for Sentinel X800 Heavy Duty Sludge Remover 1Ltr
Overall Rating: 
5 out of 5
5 out of 5
Value: 
4 out of 5
4 out of 5
Features: 
4 out of 5
4 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
4 out of 5
4 out of 5
Would you recommend this product? Yes
Overall Rating: 
5 out of 5
5 out of 5
Value: 
4 out of 5
4 out of 5
Features: 
4 out of 5
4 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
4 out of 5
4 out of 5
Good Stuff !
17 Feb 2013
By ElPresidente
, Oswestry, Shropshire
"I had a couple of blocked radiators in my system, and decided to give the x800 a try as it was favourably reviewed by others. I added 1 litre to my header tank and set the system running. Within an hour or so the system had completely cleared and was working perfectly. Well pleased with the results, and would recommend it."
2 of 2 people found this review helpful.
Review 4 for Sentinel X800 Heavy Duty Sludge Remover 1Ltr
Overall Rating: 
5 out of 5
5 out of 5
Value: 
4 out of 5
4 out of 5
Features: 
4 out of 5
4 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating: 
5 out of 5
5 out of 5
Value: 
4 out of 5
4 out of 5
Features: 
4 out of 5
4 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
5 out of 5
5 out of 5
marvellous product
23 Dec 2012
By Franglais
, cirencester costwold
"Fantastic product, I had 9 radiator blocked out of 17, so after rinsing all of them with the hose pipe in the garden the system was still not working (we have a very old system with micro pipe 8mm) i put 1 container split in 3 radiators and the other one in the tank before filling the system then nothing happenned but on the 6th day the system imbloked its self and now 16 out of the 17 are working and to be fare the last one need surgery !!! and replacement of the pipes has it did not work for 6 years. so I only can recommend the stuff !!! 1 container will treat an average of 9 radiator."
Review 5 for Sentinel X800 Heavy Duty Sludge Remover 1Ltr
Overall Rating: 
5 out of 5
5 out of 5
Value: 
3 out of 5
3 out of 5
Features: 
3 out of 5
3 out of 5
Performance: 
4 out of 5
4 out of 5
Reliability: 
4 out of 5
4 out of 5
Would you recommend this product? Yes
Overall Rating: 
5 out of 5
5 out of 5
Value: 
3 out of 5
3 out of 5
Features: 
3 out of 5
3 out of 5
Performance: 
4 out of 5
4 out of 5
Reliability: 
4 out of 5
4 out of 5
Great Product
6 May 2012
By Westmount
, Rugeley
"Does what it says on the tin
from a good product manufacturer"
1 of 1 people found this review helpful.
Review 6 for Sentinel X800 Heavy Duty Sludge Remover 1Ltr
Overall Rating: 
5 out of 5
5 out of 5
Value: 
5 out of 5
5 out of 5
Features: 
5 out of 5
5 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating: 
5 out of 5
5 out of 5
Value: 
5 out of 5
5 out of 5
Features: 
5 out of 5
5 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
5 out of 5
5 out of 5
Great Product & Great Price
6 Mar 2012
By Heatlightandpower
, London
"We power flush heating systems all the time and always use the X800. The results are great.
We always buy it from Screwfix as the price is so low."
Review 7 for Sentinel X800 Heavy Duty Sludge Remover 1Ltr
Overall Rating: 
5 out of 5
5 out of 5
Value: 
5 out of 5
5 out of 5
Features: 
5 out of 5
5 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating: 
5 out of 5
5 out of 5
Value: 
5 out of 5
5 out of 5
Features: 
5 out of 5
5 out of 5
Performance: 
5 out of 5
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5 out of 5
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a product that works
15 Feb 2012
By OILTECH
, Lincolnshire
"This product when used in a power flush machine works very well cleaning out years of muck from indirect systems and allowing radiators to once again get fully hot all the way up."
Review 8 for Sentinel X800 Heavy Duty Sludge Remover 1Ltr
Overall Rating: 
5 out of 5
5 out of 5
Value: 
5 out of 5
5 out of 5
Features: 
5 out of 5
5 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating: 
5 out of 5
5 out of 5
Value: 
5 out of 5
5 out of 5
Features: 
5 out of 5
5 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
5 out of 5
5 out of 5
Sentinel X800 (Brilliant)
1 Feb 2011
By Zogg
, Seaford
"After replacing my Pump, it shifted some muck around the system. After weeks of pops, squeeks and other terrible noises I decided that a noisy boiler was not a good morning alarm clock to have. At my local Screwfix I purchased 2 bottles of X800, X100 and X200. Many of my radiators are doubles, so needed a good dose. Drained my system and re-filled adding the X800. Left it in on a high pump speed for 7 days. Drained and flushed with water 3 times, untill perfectly clear. Finally re-filled adding X100 and X200. My Ideal condensing boiler is now so quiet I have to keep checking it's on, and I am now sleeping great, no rude alarm clock.
Thank you Screwfix, thank you Sentinel!
Peace at last.
Zogg
Seaford UK"
7 of 8 people found this review helpful.
Review 9 for Sentinel X800 Heavy Duty Sludge Remover 1Ltr
Overall Rating: 
5 out of 5
5 out of 5
Value: 
3 out of 5
3 out of 5
Features: 
4 out of 5
4 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating: 
5 out of 5
5 out of 5
Value: 
3 out of 5
3 out of 5
Features: 
4 out of 5
4 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
5 out of 5
5 out of 5
Certainly did the trick !
13 Feb 2010
By DIYSid
, Bedford
"I added 1 litre of x800 through a downstairs radiator and left it circulating in the central heating system for 24 hours. The water that came out of the system was very brown indeed. I flushed the system and then added a couple of litres of x100. The result ..... I can hardly hear the boiler now !! The noise was previously very loud with an associated whistling suggesting that the system could not remove the heat generated by the boiler fast enough. Not a problem now."
5 of 5 people found this review helpful.
Review 10 for Sentinel X800 Heavy Duty Sludge Remover 1Ltr
Overall Rating: 
5 out of 5
5 out of 5
Value: 
3 out of 5
3 out of 5
Features: 
3 out of 5
3 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
5 out of 5
5 out of 5
Would you recommend this product? Yes
Overall Rating: 
5 out of 5
5 out of 5
Value: 
3 out of 5
3 out of 5
Features: 
3 out of 5
3 out of 5
Performance: 
5 out of 5
5 out of 5
Reliability: 
5 out of 5
5 out of 5
Great Product
17 Feb 2009
By Paffman
, Ipswich
"I used the X800 without a power flushing machine and it worked wonders, clearing a problem blockage in a domestic heating system in just a day. I left the X800 in for some days with no ill effect before flushing and using X100 to protect. Superb product."
10 of 10 people found this review helpful.
Review 11 for Sentinel X800 Heavy Duty Sludge Remover 1Ltr
Overall Rating: 
4 out of 5
4 out of 5
Value: 
3 out of 5
3 out of 5
Features: 
4 out of 5
4 out of 5
Performance: 
4 out of 5
4 out of 5
Reliability: 
4 out of 5
4 out of 5
Would you recommend this product? Yes
Overall Rating: 
4 out of 5
4 out of 5
Value: 
3 out of 5
3 out of 5
Features: 
4 out of 5
4 out of 5
Performance: 
4 out of 5
4 out of 5
Reliability: 
4 out of 5
4 out of 5
Does what it says on the bottl
4 Apr 2012
By Owenc
, Wolverhampton
"When used with a power flush machine it does a great job on cleaning and flushing out your central heating system.
Cannot say what it's like just putting it in the system. I only power flush.
"