PowerFlushing?

[Householder]

Hi there,

I recently commissioned a Heating Engineer to replace my ancient 29 year old Potterton Boiler with a new Vaillant Ecotec 418 Open Vent system. Part of the Quote included PowerFlushing the Central Heating System.

His definition of PowerFlushing was to locate a special pumping machine on the landing of the house, remove the circulation Pump and fit two connectors in its place. They he spent over two hours pumping the water around the system, opening one radiator at the time. At the end of the process, he opened the drain valve and allowed gravity to empty the system until clean water flowed through.

I've just watched a Fernox video describing the PowerFlushing process and to my mind my Plumber didn't PowerFlush the system at all! In fact all he did was to pump water around the system moving any sludge and debris from one radiator to the next. At the end, no PowerFlushing was involved, only gravity was used to flush the system.

From what I understand, instead of simply recirculating the dirty water from the machine straight back into the system, he should have had a clean water inlet and dirty water outlet attached to the PowerFlushing machine. This was not done.

Please can an expert advise if I've misunderstood something here? Or am I correct in my understanding that you can't actually PowerFlush a system unless you use the special pump to force clear water through the relevant part of the system allowing an equivalent amount of dirty water to exit into a drain.

Looking forward to your replies ASAP because the Engineer is due back this afternoon and I'm considering asking him to PowerFlush the system again, properly this time.

Best regards,

Householder

 

[nysk2008]

I assume he had a machine on your landing and he was correct in removing the pump and flushing this way. Flushing machines incorporate a pump and circulate water and chimicals around the system - to be honest it sounds like he did the job as described. 2hrs is however a pretty quick flush but that would also depend on how dirty the system was in the first place

 

[nysk2008]

please also remember these machines have a separate "dump" so the final drain down would have been the final stage of the flush - I doubt very much he was just circulating and reverse circulating system water. Hope this helps

 

[Householder]

Hi nysk2008,

Many thanks for the immediate reply - much appreciated.

But all he did was circulate the same sludge around each of the radiators - surely that's not PowerFlushing is simply PowerPumping.

PowerFlushing must surely involve powered flushing of the system with clean water and allowing the dirty to flow out until sludge is no longer an issue.

Circulating and re-circulating the same sludgy water cannot surely be called PowerFlushing can it?

It certainly isn't what is shown in the Fernox Video.

Any other thoughts please?

 

[Householder]

Hi nysk2008,

Thanks for your follow-up.

That's exactly what I believe he was doing. The special pump was not connected to an inlet water supply and there was no exit attached to the pump either.

I don't know what a separate 'dump' is but the thing was only a bit larger than a vacuum cleaner so it couldn't hold very many litres of water.

And he just moved from one radiator to the next when he felt like it. The Fernox video shows that it's easy to decide when to move on because you'll see clean water exiting the pump.

Still confused!

 

[clarky101]

Did he remove the expansion tank?

 

[SimonG]

Was it a fernox machine he used?

 

[nysk2008]

your totally right in what your saying. When I flush a system I circulate clean water, then I dump it, I refill, circulate dump, refill, circulate dump etc etc - during the process I circulate water around each rad and dump, clean water again and so on; then the system is circulated fully with chemicals - anyway you get the picture. you can also look at the Kamco website that will give further information regarding flushing or alternatively kits are available for you to check if a system has been flushed adequately. Did your engineer have a hose on his/her machine to dump the dirty system water? whilst refilling with clean water?

Hi nysk2008,

Many thanks for the immediate reply - much appreciated.

But all he did was circulate the same sludge around each of the radiators - surely that's not PowerFlushing is simply PowerPumping.

PowerFlushing must surely involve powered flushing of the system with clean water and allowing the dirty to flow out until sludge is no longer an issue.

Circulating and re-circulating the same sludgy water cannot surely be called PowerFlushing can it?

It certainly isn't what is shown in the Fernox Video.

Any other thoughts please?

 

[Dotty]

Crack open a bleed valve on one of your rads, let it run into a clean rag for a moment or two, the first bit WILL be dirty (it always is regardless how good the flush is), then see how dirty your water is.

You could be worrying about nothing!

T'internet is the worst tool ever if you're looking for bad news!

 

[nysk2008]

very true, sometimes I google if I get a rash on my arm from insulation in the loft and before I even realise the internet says Ive had a stroke and got some sort of tropical disease that will kill me in hours

Crack open a bleed valve on one of your rads, let it run into a clean rag for a moment or two, the first bit WILL be dirty (it always is regardless how good the flush is), then see how dirty your water is.

You could be worrying about nothing!

T'internet is the worst tool ever if you're looking for bad news!

 

[Rickster123]

I really miss working for myself....

 

[Householder]

Did he remove the expansion tank?

Thanks clarky101,

No, but there is a Gate Valve fitted so he simply shut that down so no water could enter the system.

I hope I've understood your question correctly.

Best regards,

 

[Householder]

Was it a fernox machine he used?

Thanks SimonG,

Not 100% certain but I don't think so.

Best regards,

 

[Householder]

your totally right in what your saying. When I flush a system I circulate clean water, then I dump it, I refill, circulate dump, refill, circulate dump etc etc - during the process I circulate water around each rad and dump, clean water again and so on; then the system is circulated fully with chemicals - anyway you get the picture. you can also look at the Kamco website that will give further information regarding flushing or alternatively kits are available for you to check if a system has been flushed adequately. Did your engineer have a hose on his/her machine to dump the dirty system water? whilst refilling with clean water?

Thanks again - most helpful.

No, he didn't have a hose connected.

He simply opened the bleed valve near the Boiler on the ground floor and open the Gate Value to the expansion tank to allow new clean water to flow through via gravity. The pump had been disconnected by the time the flush was carried out!

Best regards,

 

[clarky101]

Depending on the machine but Did he have a hose attached to a cold mains anywhere.....maybe loft

 

[Householder]

Crack open a bleed valve on one of your rads, let it run into a clean rag for a moment or two, the first bit WILL be dirty (it always is regardless how good the flush is), then see how dirty your water is.

You could be worrying about nothing!

T'internet is the worst tool ever if you're looking for bad news!

Thanks Croppie,

I obtained a Magnabooster MB3 (He'd never heard of such a thing!) and he fitted it for me (after I showed him the internet video).

Earlier today, I opened the drain valve on the MB3 and drained out TWO BUCKETS of crap before clean water ran through.

The system was only fitted 10 days ago and I've only run the Boiler for 1 hour because I've been away.

I'm convinced that he didn't use the PowerFlushing machine properly and simply circulated the sludge and then allowed gravity to remove a small proportion of it.

Best regards,

Householder

PS. Couldn't disagree with you more about this Internet. I've used it to save lives - literally!

 

[Householder]

Depending on the machine but Did he have a hose attached to a cold mains anywhere.....maybe loft

No, that's my point. No clean water was entering the system. He was just circulating and recirculating water after adding a cleaning agent.

 

[nysk2008]

If that's the case by the sounds of it a full "powerflush" wasn't carried out; however I also believe vaillant don't specify a powerflush only a system clean which could by rights be interrupted in a number of ways - if he quoted on a powerflush you may need to get him back, if he quoted on a system clean/flush then sounds like he has

No, that's my point. No clean water was entering the system. He was just circulating and recirculating water after adding a cleaning agent.

 

[Rickster123]

The magnabooster is designed to catch the "crap". Even when a system is fully power flushed its practically impossible to remove it all. If the water ran clean and all is working well and heating well where is the issue? I just think you will have a real job trying to get him to flush it again.

 

[Scott_D]

Was the machine a magnacleanse?

 

[AWheating]

If that's the case by the sounds of it a full "powerflush" wasn't carried out; however I also believe vaillant don't specify a powerflush only a system clean which could by rights be interrupted in a number of ways - if he quoted on a powerflush you may need to get him back, if he quoted on a system clean/flush then sounds like he has

Boiler manufacturers do not normally statethat you need to use a power flush machine, they require you to flush the system to the current british standards which in many cases would require the use of a machine dependant on the systems condition. The british standard is about the system condition and leaves the method used to clean the system the choice of the installer. Normally 3 methods are exceptable, gravity, mains flush and machine.

 

[AWheating]

to me its sounds like you did not get a real powerflush. The correct method takes a number of hours and alot of equipment to do it correctly. Taking water samples as you dump dirty wata from each rad untill its almost drinkable.

 

[JeffD]

If your power flushing without magnets then you must flush n dump each rad till crystal clean, flushing with magnets you'd se the sludge on the magnets when he was cleaning them.

 

[AWheating]

you always need to dump, magnets only remove magnetic particals after all. you should dump till your tds/ph readings are correct or you can see the circles

 

[JeffD]

Yes I agree with that, you should dump all system cleaner out before flushing and dumping then you will get a true reading with TDS

 

[supper plumb]

HOW TO REMOVE RADIATOR SLUDGE - Plumbing Tips - YouTube
FERNOX TF1 COMPACT INSTALLATION - Plumbing Tips - YouTube
REMOVE AIRLOCK FROM RADIATOR - Plumbing Tips - YouTube

this is flushing but not power flushing
toms top tips how to flush a combi system - YouTube

 

[JeffD]

There's only one right way to powerflush for the correct result, I wouldn't go down the YouTube route :hammer:

 

[Deleted member 32524]

If you don't think it has been done properly test the water with some ph paper. A few quid for a roll. Should be around 7. Test the total dissolved solids, get mains water test it, then test the central heating water. If he has added inhibitor it will be higher than the mains. Think about 800.

 

[ed209]

It would take the best part of a day to power flush correctly even then I'm not convinced its that effective I've found one of the best methods assuming all the rads work to some extent is to put in some sentinel X800 and let that circulate over a couple of days then do a complete drain down several times.
Did he charge for a power flush? This can add a significant amount to a boiler change if you specifically wanted a power flush.

 

[JeffD]

It would take the best part of a day to power flush correctly even then I'm not convinced its that effective I've found one of the best methods assuming all the rads work to some extent is to put in some sentinel X800 and let that circulate over a couple of days then do a complete drain down several times.
Did he charge for a power flush? This can add a significant amount to a boiler change if you specifically wanted a power flush.

Id like to se you put x800 in a very stubborn cistern, when you drain it down do you think your removing all iron, power flushing as been out for years and if done properly you can definitely get 20% saving on gas bill of boiler, this is a proven fact, all you are doing with x800 and boiler running is munching it up but you need to get it out of the system.

 

[ed209]

It was a bit early when I wrote that Jeff
But I have found x800 to be very effective and was not suggesting you put it in a stubborn system just one that is functioning reasonably well just to further cleans it. The power flush bit got me when you now have the additional magnet filter option, this says to me that power flushing without is not very effective or is it to speed the process up?
But as stated a proper day long power flush can add a lot to a boiler change.
Money you would be better off spending on a chemical flush through and a decent in line filter on the rerun pipe that works as the rads/pipe/fittings/boiler breakdown internally over the years
But just my opinion I'm always interested in other methods that I have read on here and other forums.

 

[ed209]

Sentinel now do X400 which is designed to stay in the system and work in conjunction with a filter
I have no connection with Sentinel by the way

 

[AWheating]

a powerflush machine works alot better than just a chem because of the extra flow rate/movement in the system created by the machine.

in many cleaning processes the use of a combination of cleaning chemicals, heat and movement are the ideal/ best method. think of your washing machine using a cleaner, adding and warming water and spinning it around as an example.

one way of looking at it is.......... you want to clean some dirty slabs, you mix a cleaner in hot water and apply it on the slabs to let it loosen the dirt. You then can either swill it off with a bucket of water or use your garden hose with mains pressure. not a very good example i grant you

 

[ed209]

Well I suppose that was was I was getting at by putting the chemicals in and heating the water and movement around the system for a couple of days or more by the pump running the boiler, then a complete drain down.
I'm not anti power flush and have used mine very successfully where necessary.

 

[JeffD]

Yes everyone to there own, I just think a boiler won't move iron oxide like a flushing machine will but if it works for you then that's all that matters.