Sentinel X400

Soldato
Joined
12 Sep 2003
Posts
10,442
Location
Newcastle, UK
Hey, our heating system is in need of a clean. It hasn't been done for many years and one of the towel rails was blocked with sludge yesterday. Never been off in 20 years! Took it apart and fixed it all. The water was black.

I'd like to run some X400 through the system and flush.

We have 13 radiators. Mostly double panels including 3 large towel rails. The dosage says 1 tin will do 8-10 rads in a typical system. Should I just get one or do you think a double dose would be safe?

I then plan to run it for a fortnight before flushing.

Thanks!
 
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X400 is a good start and yeah stick 2 bottles in.
In an ideal world you would have a system filter that will hold onto the sediment as its broken down rather than have it run round the system.
You can keep it in the system for around 4 weeks, but 2 should be fine, as long as you actually use the heating regularly to keep it doing it's job.
Make sure your properly drain the system till everything is empty, not just flush through a leg of pipework.
Add 2x inhibitor and you should be fine.
 
Smashing thanks. :) Gone ahead and ordered the 2 bottles of X400. I also as you say, plonked in x2 inhibitor and also the noise reducer as well into the order.

Cheers.
How did you get on with this in the end, did the cleaner resolve any blockages? I have a heating system that has three radiators out of sixteen that just don't get very warm as well. I took one off the wall and flushed it out but it still stays cool, so the piping seems to be partially blocked so thinking of putting in a cleaner as well.
 
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How did you get on with this in the end, did the cleaner resolve any blockages? I have a heating system that has three radiators out of sixteen that just don't get very warm as well. I took one off the wall and flushed it out but it still stays cool, so the piping seems to be partially blocked so thinking of putting in a cleaner as well.

Have you tried balancing the radiators? i.e. reducing supply to some in order to boost supply to the cooler ones?
 
Have you tried balancing the radiators? i.e. reducing supply to some in order to boost supply to the cooler ones?
Thanks for your reply, yes everything has been tried, switching all the radiators off only leaving the ones that don't get very warm on, bled them and even flushed one radiator out with no success. We had the oil boiler serviced last week and flushing the system with a cleaning agent was suggested. It's 20 years old with small bore piping and in very had water area as well.
 
Just to check - I'm not talking about switching radiators off at the control valve end (usually 0 to 5), I'm talking about adjusting the lockshield valve at the other end, the return valve. I had microbore piping in one property and I found I could improve some radiators by adjusting the lockshield valve on others. It could just be a poorly designed system in terms of internal pressures which means water won't easily get to certain radiators. Flushing it can only improve matters. However, it could be a total blockage from limescale build up.
 
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Just to check - I'm not talking about switching radiators off at the control valve end (usually 0 to 5), I'm talking about adjusting the lockshield valve at the other end, the return valve. I had microbore piping in one property and I found I could improve some radiators by adjusting the lockshield valve on others. It could just be a poorly designed system in terms of internal pressures which means water won't easily get to certain radiators. Flushing it can only improve matters. However, it could be a total blockage from limescale build up.
Thanks again, yes nothing changes when the lockshields are adjusted on the working radiators and the guy who serviced the boiler tried all of this. If the cleaner doesn't work then we'll get someone in to powerflush the system. But we're aware that if the pipes cannot be unblocked we're looking at redoing all the pipework but the expense doesn't bear thinking about.
 
Hi, yes it helped in a fashion.

Ran it for 2 weeks and emptied it out, and it improved most rads. They are nice and hot to the touch. However, one rad still like warm. Took it off and flushed a load of crap out but still no dice. We ended up replacing the valves and that sorted it.

But the cleaner I feel definitely helped in a more general way.

I don't have microbore pipe but can imagine it can gunk up quite easily over the years.

Hopefully running the flush through will yield some improvement for you.
 
Hi, yes it helped in a fashion.

Ran it for 2 weeks and emptied it out, and it improved most rads. They are nice and hot to the touch. However, one rad still like warm. Took it off and flushed a load of crap out but still no dice. We ended up replacing the valves and that sorted it.

But the cleaner I feel definitely helped in a more general way.

I don't have microbore pipe but can imagine it can gunk up quite easily over the years.

Hopefully running the flush through will yield some improvement for you.
Thanks, I have the cleaner to do it with now and whilst the system is drained down I plan on replacing the valves on any rad that isn't getting warm as a precaution anyway. There is only three so not a great cost to do.
 
So system was drained down and refilled with the cleaner, I had a bit of an issue with an air lock to start with but found that the pump had a 'purge' setting and that cleared it. So now running the system with all the radiators that get hot turned off and only the ones that stay cold on, with their lockshield valves fully on.
No sign yet of anything shifting but it's only day 2.
Both the pipes running from the boiler are getting very hot now which I hope shows they aren't blocked.
 
So system was drained down and refilled with the cleaner, I had a bit of an issue with an air lock to start with but found that the pump had a 'purge' setting and that cleared it. So now running the system with all the radiators that get hot turned off and only the ones that stay cold on, with their lockshield valves fully on.
No sign yet of anything shifting but it's only day 2.
Both the pipes running from the boiler are getting very hot now which I hope shows they aren't blocked.
If you only have the non working rads turned on, and yet both flow and return pipes are getting hot, then that means the flow is moving through a bypass of some description. That in itself needs investigating, as a simple gate valve setup will permanently take flow away from parts of the system, which isn't ideal. It should be a proper bypass valve, correctly set. Which can be shut down, to help short term, while pushing chemical around, to clean the extremities. You'd want to lower the boiler temperature when doing that, so not to cause an over heat scenario. All normal stuff for a heating person :)
 
If you only have the non working rads turned on, and yet both flow and return pipes are getting hot, then that means the flow is moving through a bypass of some description. That in itself needs investigating, as a simple gate valve setup will permanently take flow away from parts of the system, which isn't ideal. It should be a proper bypass valve, correctly set. Which can be shut down, to help short term, while pushing chemical around, to clean the extremities. You'd want to lower the boiler temperature when doing that, so not to cause an over heat scenario. All normal stuff for a heating person :)
Thanks, the bypass was mentioned to me by the guy who did the boiler service when we had a bad air lock in the system due to him partially draining the system down and it was then bypassing, but we released the air lock and it stopped bypassing. Now, unlike before, where the boiler would just go to standby, or what I call ready or 'sulking' mode, for ages without it firing up once the set boiler temperature had been reached, it now appears to be cycling far more often.
There is an overheat sensor though, it has kicked in once over the year we've been in the house when I had the boiler set high but he said this wasn't unusual for a boiler 20 years old and that's probably due for a replacement at some point as well.
However I'm sure I am doing what he told me to do, which was to run it with all the radiators off aside from the ones that stay cold and the pipes going to the radiators do seem to be blocked because they get luke warm on two and stay cold on one. However I do plan to take those radiators off the wall, when the system is drained again, and give them a good flush out. Maybe lightly rod the pipes going to the rads with some wire and replace those valves also.
I bow to your greater knowledge though and very much appreciate your contribution.
 
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