Canyou power flush a combi boiler???

[Jaybee 45]

Hi all,
can a combi boiler system be power flushed? and if so is there any special do's and don'ts? I can borrow a machine and a plumber I know will do the work although he has not used a power flush before. I have also bought a magnaclean to be fitted at the same time. Any advice mcuh appreciated .

 

[gas4you]

Yes no problems. I usually cut into the flow under the combi and us the filling loop connection on the return if they are accessible.

Isolate the combi after a few minutes, so the chemical has got in it, then flush rads etc just through flushing machine. At the end turn off all rads and open boiler valves to flush out boiler.

Magnaclean will go in the return.

 

[hi-spec plumbing heating]

or i use the pump adaptor.

 

[Jaybee 45]

Hi Dave,

I downloaded some info and it says to clean each radiator in turn http://www.aquaplumbservicesltd.com/flushing Is this neccesary or can the whole system be flushed from one point??
By the way I notice you are from one of my favourite places. We visit Barnham Broom usually twice a year for golf and always pop into Norwich to do some shopping

 

[JohnD]

put in a cleaning chemical such as Sentinel X400 a couple of weeks beforehand (no need to drain for this). it will loosen old sediment and make the cleaning process much more effective. As it is winter now you can be circulating it round all the radiators to start getting then clean. It does not remove old sediment, it just softens and breaks it down so that it will be suspended in the water and easier to flush out.

After the flush, when refilling, be sure to add a Corrosion Inhibitor to prevent future corrosion and keep the system clean.

 

[gas4you]

Hi Dave,

I downloaded some info and it says to clean each radiator in turn http://www.aquaplumbservicesltd.com/flushing Is this neccesary or can the whole system be flushed from one point??
By the way I notice you are from one of my favourite places. We visit Barnham Broom usually twice a year for golf and always pop into Norwich to do some shopping

Yes I've used Barnham Broom quite often in the past. I like the pool and sauna there.

Each rad will be flushed individually even when connecting to a single point.

Use a chemical such as X800, run for an hour, then drain as much out of the machine as possible, fit the soft flush adapter, then you will turn off all rads bar 1 then flush through with cold mains until it runs clean in the drain, then turn that rad off then open the next and so on.

Gentle banging of the bottom of the rads with the palm of your hand will help dislodge some extra crud.

 

[hi-spec plumbing heating]

you flush whole system from one point and shut all rads then open one rad flush for 5mins then open another rad and shut the first one.
then each rad getts full flow through it.

i always use fx2 in powerflushing. but you must neutralise the system after as it is acid based.
and be careful if you have ali rads or heat exchanger

 

[Jaybee 45]

Thanks to all of you.

I don't know what I'd do without you guys' know -how. So much great advice on this site. Jean B (aka Blod )

 

[bengasman]

Pump adapter is the best place to connect the power flush machine. If done properly, there is absolutely no need for a magnaclean after

 

[powerflushingpro]

Yes it can be power flushed, but it's recommended by the powerflush association that you do not use acid to do the flush, that the company do NOT connect to the boiler's internal pump as it can cause damage and that if you are having hot water problems. The plate heat exchanger should be completely removed and both descaled and power flushed to make sure all the sludge and scale is removed.

 

[expertgasman]

Yes it can be power flushed, but it's recommended by the powerflush association that you do not use acid to do the flush, that the company do NOT connect to the boiler's internal pump as it can cause damage and that if you are having hot water problems. The plate heat exchanger should be completely removed and both descaled and power flushed to make sure all the sludge and scale is removed.

Blodwyn, the OP , last appeared over one year ago/

 

[Agile]

I would say that it was all FOUR years ago!

Nor do I agree with the answers given above.

Power flushing needs a certain degree of skill both to choose the most appropriate chemicals and as to how it should be done and particularly in respect of the inside of the boiler.

I dont think that a plumber who has never done power flushing before is going to make a very good job of it.

Tony

 

[powerflushingpro]

I agree that power flushing is a very skilled job where you needs loads of training and experience. Have done over 250 myself and I am still learning new things. You can't just watch a youtube video and think your an expert, you will more likely cause damage before you do the power flush properly.

 

[mysteryman]

You need to get the diverter valve in mid-position when powerflushing a combi, otherwise you are not cleaning the primary side of the hot water circuit within the boiler. This is not just the plate heat exchanger, there are the waterways and ports here and there. Read the Service instructions!

 

[mickyg]

You need to get the diverter valve in mid-position when powerflushing a combi, otherwise you are not cleaning the primary side of the hot water circuit within the boiler. This is not just the plate heat exchanger, there are the waterways and ports here and there. Read the Service instructions!

dont be silly, if you do that then you cant put full flow through individual radiators. Do it in both positions, seperately. Dunno why matey above thinks connecting to a combi pump block will cause damage. Thats nonsense.