power flushing central heating myself?

Soldato
Joined
29 Jul 2003
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hi guys

got cold spot at bottom of 3 radiators. then need power flushing the system.

i have some knowledge of the combi central system. i replaced teh diveter valve and PCB in my boiler myself (isar ideal HE30). i am confident that i can do the power flushing by myself. my water system is high pressure so i guess the pressure could flush them out?

any tips would be great.

thanks
 
hi guys

got cold spot at bottom of 3 radiators. then need power flushing the system.

i have some knowledge of the combi central system. i replaced teh diveter valve and PCB in my boiler myself (isar ideal HE30). i am confident that i can do the power flushing by myself. my water system is high pressure so i guess the pressure could flush them out?

any tips would be great.

thanks
Seeing as you're gas safe registered, surely you know how to power flush a system.
 
Isolate boiler from pipework


Connect mains water via hose to pipe work/another hose to `far end`of pipework
turn off all rads except #1
Turn on mains for x mins
Turn on #2 rad turn off #1 rad then rinse and repeat for all rads
Remember that mains water pressure is about 4 BAR??? so if you have any `dodgy` joints the could pop and you end up with water everywhere:p
Do this at your own risk of course
 
Easier just to take the rads outside and flush them manually, cheaper as well. Or even better just replace them. But seeing as you're gas safe you should probably know how to power flush.
 
Remember that mains water pressure is about 4 BAR???

Mains pressure can be up to 10 bar, and I doubt very much radiators can withstand mains pressure. Even though most boilers are rated up to 10bar mains, the heating is protected by a 3 bar relief valve. So applying mains pressure to a radiator can be very risky, but also very funny when they explode, so make sure you video it
 
ummm you don`t pressurise the rads which is why I clearly said turn on #2 before turning off #1 :)
Re pressure,that is assuming you don`t have a solidly blocked rad or length of pipe:p
 
Seeing as you're gas safe registered, surely you know how to power flush a system.

Easier just to take the rads outside and flush them manually, cheaper as well. Or even better just replace them. But seeing as you're gas safe you should probably know how to power flush.

Where did I said I'm gas Safe?!?

Thanks guys.

I think it'll be easier to remove the radiators and flush them out at outside
 
Won`t clean the pipework though :)

Good point. Ive googled for power flushing, some reviews said power flushing is waste of money. As most dirts are in radiators so removing the rads and flush them out is enough.

Even professional power flushing don't remove 100% dirts anyway
 
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Just put some x400 in the system and flush/wash the rads a couple of weeks later, once the chemical has had time to break down the sludge. Alternatively put x800 in for a fast clean once ran for an hour or so. In either case run the system warm, to give the chemical a good chance.

If you have a system with heavy deposits and cold areas then consider DS40, but be warned, it will find weak spots within your system. But does an amazing job of cleaning a heating circuit.

Once you've done, dose up on inhibitor. Over dose, don't under dose.

Mick
 
My pipes were clogged something rotten, i doubt even a powerflush would have shifted some off the gunk in my system. I'd not even consider using a powerflush on a system with push fit connection, i'd be too scared.....of the wife when it went wrong! I even own a power flusher, only cost £70 from ebay!

Rads respond well to a hose flush, helps to tap them with a rubber mallet aswell, i'd take the rads off and flush them down the garden, and just try and flush the pipe work with mains water, you can sometimes use the filling loop to do this. X400 left in for a few weeks is a good bet, i didnt have much success with x800 (fast clean) in the system for an hour.
 
If you have a system with heavy deposits and cold areas then consider DS40, but be warned, it will find weak spots within your system. But does an amazing job of cleaning a heating circuit.

Mick

DS40 is meant to be the best cleaner, but its pretty harsh, and isnt good if you have aluminium components in the boiler, so best used with the boiler isolated and a powerflush to do the circulation.
 
Is that right? I thought unless you disturbed the gas train you could touch the electrical sides fine.
 
You can do what you want in your home, as long as your actions don't cause harm to others. Your insurance company might see things differently tho! And so might the wife ;)

You cannot do work on any part of a gas appliance or its installation (gas water electric etc) or building or alteration work that could affect a gas appliances safe operation in any other persons home without being suitably qualified, ie gas safe registered and qualified in the relevant subjects. That would be breaking the law and open yourself up to prosecution or if you cause harm, prison.

We see this stuff reported in the gas safe magazine each month.

Mick
 
I just don't think it's worth the risk, maybe if it was just your own life you're putting at risk but you see when things go wrong and it takes out your neighbours as well. For the sake of a few quid.
I no doubt would be capable but im leaving the boiler to the professionals and doing only the plumbing myself.
 
But how would you know that whatever electrical part that has been changed hasn't effected the boilers performance and safe operation?

Fair point, but changing a pcb isnt rocket science nowadays, all the connections are keyed, same goes for swapping out a diverter valve. Touching anything burner related,unless you possess flue gas analyser, i wouldnt advise any layman to touch.

As an aside Ive done training (i work for a major controls and valve manufacturer) at industrial burner manufacturers, and whilst im not gas safe, ive come across some Corgi engineers I would even let through the door to look at my boiler let alone work on it,I hope the quality of engineer has moved on, but judging by some of the daft questions ive gotten in recent years, im not convinced by the acreditations that exist.

All said and done, if you struggle with understanding the boiler manual, then common sense dicates you shouldnt go near a boiler, as said above, its not worth the risk.
 
You get good and bad workers in all walks of life. But gas regs aren't fussed about the nitty gritty of what's water, gas, electric, or individual components. It's all about what actions someone takes and the effect or potential effect that could have on an installations safe operation.

Just a heads up, it doesn't matter what part you change yourself, it's how you leave the appliance. I know plenty of control boards that need calibrating to the appliance, and most manufacturers would require you to do relevant safety checks, like combustion analysis, even if you have just changed a straight swap PCB. Things you can't do without the relevant training, knowledge, & equipment.

Mick
 
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