POWER FLUSH OR NOT

[mutlow]

Hi, we have a gloworm ultimate boiler, problem is it fires up and within about a minute or two the red cut out switch pops out and it no longer works! The pump in the airing cuboard appears to be red hot also.

My house is around 10 yrs old although we have only been here around 18 months, we have a cover with British gas and I seem to think they changed the pump when we moved in.

They came out again before xmas becasue of this fault, and the guy was indicating that if it happens again we may need a power flush.

I have since spoken to an old friend who fits for British gas and he states that is rubbish on a 10yr old old house and its BG's way of getting a grand from you!

Any ideas?? Engineer is coming out Friday.... and I am dreading the power fluch word!

Thanks

 

[bigbeak07]

exactly, if i had a pound for the amount of times ive been to jobs and british gas have recommended a power flush id b loaded! this is a get out clause for them! wish i had there job lol! don't agree to a british gas power flush could cost ya £800+, shop around cause u'll get it half the price from smaller firms!
If i were you id get someone to add a chemical called sludge remover first, if this doesn't work then u'll have to powerflush it!

 

[JohnD]

red hot pump = pump probably jammed

take out the screw in the middle, see if the spindle is spinning. If not, turn it off and see if you can move it with a screwdriver in the slot

could possibly be a shortage of water - if you bleed the highest rad in the house, does water squirt out vigorously?

might be black sediment - when you bleed a rad into a white tissue, what colour is the water?

is this a sealed pressurised system, or has it got a feed and expansion tank in the loft?

do you know where the drain cock(s) are?

you can give it a chemical clean yourself for about £30 and a couple of hours work - this will quite likely do the trick

is it microbore?

do you know how to do simple plumbing?

 

[mutlow]

Hi, thanks for the prompt replies... if I remove this screw.... could I be in bother... I am no DIY man.... am I likley to get a face full of water like you see on the tv?

Without sounding too thick, how do I find the highest rad in the house??

From being on the loft I remember 1 x big tank and over the other side a much smaller one?

Err drain cocks???

 

[JohnD]

there will be no more that a few drips of water when you take the screw out. a rag will catch them

the highest rad in the house will be upstairs

check in the loft. If you have a small F&E tank it will be very easy to do a chemical clean. Note how deep the water is and see if it has mud at the bottom. There is a chance it might be empty. It has a bal valve in it, like in a toilet cistern. Press the float down to check it works.

drain cock should be by one or more of your downstairs radiators. It is for draining the water out of the rad pipes

or

might be by the radiator nearest the back door (so you can put a hose outside. Might be near the boiler.

Microbore is radiator pipes as thick as a pencil. More common is 15mm pipes as thick as your finger.

 

[mutlow]

Dont feel overly confident in stripping the motor just yet.... plus its bloody hot!

Eventually found a bleeding key, bearing in mind the system is cold and not running I tested a rad in the ensuite and the water came out straight away.... no hissing just came out like a tap.... not spirting but a steady stream. On white tissue it was 110% clear??

 

[mutlow]

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.

Thanks again

 

[JohnD]

OK. turn off the boiler (and the pump will start to cool down). Find your big screwdriver that fits the big screw, and a torch. Go and look in the loft at the small tank.

You have found the drain cock.

When you come back the pump will be less hot so you can take the screw out. It is only an inspection screw, you take it out so you can look inside. Water will not squirt out as there is a water seal round the spindle inside, and you will not do any damage by removing it (do not lose the screw; if you don't put it back there might be a slight drip, so put a plate or tray under the pump while you undo it.) You can use the torch to peer through the screwhole at the pump spindle.

If you can set it moving with your small screwdriver turn the boiler on and go back to see if the spindle has started spinning.

 

[mutlow]

Does the clear water from the rad I just bled tell you anything.... or not??

 

[JohnD]

clear water may be a good sign. If there was a lot of loose sediment in the water it would be black (or brown, which is rust, and a worse sign). However there may be old black sediment that has hardened into blockages, this may be contributing to your problem. We will know more after the next test (once you have checked the F&E tank and the pump).

Take a bit of string with you into the loft - after you have looked in the F&E tank, tie up the float so that the valve will not let in more water if the level is the F&E drops (this is only temporary, you will remove the string before the evening is finished).

Have you got a capable assistant with you in the house?

 

[mutlow]

Quick progress report....

Eventually turned the big screw on the pump (by the way, there is no way that pump is new), then there was a lot of hissing and clonking and banging! Black water came out.... although black it was thin if you get my meaning.... it then sounded as if water was running through all the pipes in the airing cuboard. Sounded a bit scary so I swiftly tightened the screw up again!

The cut off switch has stayed in now for quite some time and my rads are getting hot.... job done.... or not?

 

[JohnD]

not yet.

I reckon your pump was jammed with old black sediment.

there is probably quite a lot of it in there so it is liable to jam again..

Have you tied up the ball float in the F&E tank?

If not, do it now. Then use a small adjustable spanner to open the drain cock and let water run out into a basin.

Then close the cock and go into the loft again. You will hope to find that the water level in the F&E tank has dropped by the amount of water that you drew out from the drain cock. I hope so. If not you have a blockage in the feed pipe and you will need professional help.

Then remove the piece of string and let the float drop down and the valve should fill up the F&E tank again.

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. Don't buy a cheap own brand or a different chemical as it may not work the same. It will cost you about £15

I will explain how best to use it tomorrow.

Then you can go to bed.

Using this chemical will loosen the sediment that has been causing the problem and most likely will save you having to have a powerflush. It will start working immediately but may take several weeks to loosen as much sludge and sediment as it can.

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). Tell him the pump is very old and had jammed, but that you managed to free it, and say that you think he should fit a new pump.

Ask him how much he would charge to fit a Magnaclean (I will tell you more about that tomorrow)

 

[mutlow]

Cut out switch has popped back out again.... wont go back in at the moment either.

Released the big screw again, lots of steam and hissing, tightened it bavck up again.... you could hear a wheel moving. The black water started running clear.

Looked in the loft... not for too long as I dont do lofts.

The 2 tanks are close together not like I first stated. The little tank was about half full, the water was a little murky but certainly not sludgy, put my hand to the bottom of the tank.... the base you could write your name in yes but only due to a very thin layer of rust on the bottom. You could see through the water but you would not want to drink it!

 

[mutlow]

Dont feel confident in doing all that, can I just bung some of that chemical in the small tank anyway.... and pray?

 

[JohnD]

You can put the chemical in the small tank BUT it will not be drawn down into the radiators. To draw it down you have to draw a bucketful of water out of the drain cock. Then the system will be replenished from the F&E tank, carrying the chemical with it.

So you have got to open that drain cock

I strongly recommend that you also bail out that sludge from the F&E tank into a bucket and sponge it clean first - that will prevent you adding more sludge into the pipework.

Praying does not work.

Keep reminding yourself that this is saving you £800 or so.

Send your wife up into the loft, if you have one.