POWER FLUSH OR NOT

[bengasman]

Rough test is really simple.
Run the system for a couple of hours and feel along the bottom of downstairs rads. If it is colder in the middle than at the sides, you need a flush.
Should be a faq about this.
Search forum for flush with chemicals and do that first.
It may work, it may not depending on how settled the dirt is. If it does not work with chemicals, get a powerflush done by a local chap.

 

[mutlow]

I guess I know what you are saying!

Cut off switch has popped back in... rads are warning.... but not for long I guess!

The pump is a DAB and looks old.... Think BG are out on Friday, I shall see what he says to fitting a new one!

Also in the airing cuboard are 2 things that "look" like motorized valves, I wriggled one back and fourth, the other I just touched and the black bit that sticks up dissapeared..... not sure what all that was about!

Thanks so far.... will look for a spanner in the morning.... off out to the garage to warm up now

 

[mutlow]

Good suggestion re feeling the middle of the rad.... if only I could get them hot!

 

[Softus]

I reckon your pump was jammed with old black sediment.

The ports might well be caked, but I reckon it was airlocked.

Then use a small adjustable spanner to open the drain cock and let water run out into a basin.

Do not do this without a hose to hand. The risk you run is that the washer breaks up and you cannot reseal the drain off, so you'd have black water and gunge everywhere.

The reward (of not draining fully) is questionable, and in any case doesn't justify the risk. On any system with this degree of degradation I would never attempt to drain off a small amount - always drain fully and then you can change the DOC washer for a new one and have full control.

If not you have a blockage in the feed pipe and you will need professional help.

Well, possibly not. Many amateurs receive enough help on this forum to do the job themselves.

However, given the weather that we're expecting this week, if you're an amateur then I wouldn't even start this until Saturday morning.

If that test is satisfactory, write yourself a note to go to the DIY shed or plumbers merchant tomorrow and buy a litre bottle of SENTINEL X400 which is a cleaning chemical that breaks up the black sediment.

Hm. I think you're expecting a bit too much from X400. It won't do much to hardened sediment.

Using this chemical will loosen the sediment that has been causing the problem and most likely will save you having to have a powerflush.

I wholly disagree. X800 perhaps, with a following wind, but if a powerflush is to be avoided you'll need a stronger army than X400.

If the BG man arrives before you have done this, explain to him that you would like to do a chemical clean yourself with X400 and that you believe that will remove the loose sediment (he may say that it might not, but it will be difficult for him to claim that it won't).

Not difficult at all, IMHO.

Tell him the pump is very old and had jammed

But it hadn't jammed!

 

[JohnD]

why do you say airlocked not jammed?

 

[mutlow]

Several times now I have undone the big screw on the pump, it has hissed and steamed, banged and crashed so I have tightened it up again, as yet I have not taken the screw out completley, I aleady have burnt hands from the hot water!

But after I have carried out the above, I can get the heating working for around 10 minutes, then the switch pops out again on the boiler!

The water runs black from the pump for a short while, then clear.

Surely if a power fluch was needed I would not get clear running water.... or is that not the case??

 

[JohnD]

The rad near the front door has a chrome thingy pointing downwards like the chrome one in your picture above.... accept mine points down and your is at a slant!

Just before Xmas BG had to change a constantly leaking joint on that rad near the front door, he ran a hose from that chrome thingy to outside whilst he done it...

house is 10 years old, so I hadn't thought that the DO would be rotted, and it was recently used..

On the (one) occasion I used X400 I got a LOT of old black sediment out of a 30-YO system (all trapped by the Magnaclean) after having done a plain-water drain and flush, so it seems to me pretty good at loosening old black sediment

 

[mutlow]

Sorry DO?? (what does DO mean)

 

[tonybhoy]

Several times now I have undone the big screw on the pump, it has hissed and steamed, banged and crashed so I have tightened it up again, as yet I have not taken the screw out completley, I aleady have burnt hands from the hot water!

But after I have carried out the above, I can get the heating working for around 10 minutes, then the switch pops out again on the boiler!

The water runs black from the pump for a short while, then clear.

Surely if a power fluch was needed I would not get clear running water.... or is that not the case??

It's doing that because your boiler/system has overheated.

You'll have to let it (boiler/system)cool down and the boiler and pump are switched off before you can try again.

Sounds as though your pump is gubbed.

Those Dabs pumps are pure pish mate.

Hard to say about the water quality but the first thing I would try is the pump.

BG don't like changing pumps cause there's not as much profit in doing that as there is with the power flush and they will probably change the pump when they do the flush anyway so they can cover their arse.

 

[tonybhoy]

Sorry DO?? (what does DO mean)

Drain off.

 

[Softus]

why do you say airlocked not jammed?

Just a hunch. There's isn't enough information to be certain of either condition.

If the pump is jammed it could be because it's overheated. The situation is best assessed with system completely cold.

If the pump doesn't run when cold, the next step is to replace it - there's no point in adding X400/X800 without a running pump.

Just before Xmas BG had to change a constantly leaking joint on that rad near the front door, he ran a hose from that chrome thingy to outside whilst he done it...

house is 10 years old, so I hadn't thought that the DO would be rotted, and it was recently used.

They don't rot - they harden and break up. If the DOC was used recently without changing the washer, then the risk is increased, not reduced.

On the (one) occasion I used X400 I got a LOT of old black sediment out of a 30-YO system (all trapped by the Magnaclean) after having done a plain-water drain and flush, so it seems to me pretty good at loosening old black sediment

Personally, I'd feel immensely uncomfortable attempting to make a product comparison, and give a recommendation, on the basis of just one occasion.

 

[mutlow]

Your right it is a DAB pump.... did not think I had mentioned that!

I actually have the insurance.... costs about £200 a year inc a service and covers pretty much everything.... but a power flush!

I will let it cool off and give it a whirl then.

 

[JohnD]

...Personally, I'd feel...

That's us DIYers for you!

 

[tonybhoy]

Your right it is a DAB pump.... did not think I had mentioned that!

I actually have the insurance.... costs about £200 a year inc a service and covers pretty much everything.... but a power flush!

I will let it cool off and give it a whirl then.

They make a fortune from power flushing.

The annual service charge whilst expensive is actually a pretty good deal if you have a system that requires constant attention so in order to even things up they push or 'advise' you get a PF done for about £600 but most 'normal' houses could replace all of the rads for that price.

Why would you spend £600 on old stuff when you can get new stuff for the same money?

Never made sense to me however they make it a condition of your contract once they get a 'sniff' of sludge that your contract is limited if you don't have a PF done.

Believe they will change a rad once and 'advise' re PF and if you decline then the other rads in they system are no longer covered on the contract.

 

[nickso]

They make a fortune from power flushing.

they dont actually.

The annual service charge whilst expensive is actually a pretty good deal if you have a system that requires constant attention so in order to even things up they push or 'advise' you get a PF done for about £600 but most 'normal' houses could replace all of the rads for that price.

what?? 10 rads plus labour plus chemical plus a lifetime guarantee to to replace those rads again if they go all black again?, you must be losing money hand over fist man.

Why would you spend £600 on old stuff when you can get new stuff for the same money?

see above, in "most cases" you cant.

Never made sense to me however they make it a condition of your contract once they get a 'sniff' of sludge that your contract is limited if you don't have a PF done.

this clearly makes you out to be a poor businessman. something almost entirely out of their control is not covered by the contract, but this makes no sense to you.

Believe they will change a rad once and 'advise' re PF and if you decline then the other rads in they system are no longer covered on the contract

you got something right at least. they will change as many rads as you need, provided the water that comes out of the rads is not in some way contributing to the demise of said rads. not only that but any water part that is subsequently damaged due to that water is also not covered. harsh isnt it