Flushing out hot water?

[glennybee]

Hi folks,

I've been having problems recently with my hot water, sometimes its hot, mostly its not lol. It still flows out the tap at the same rate but it's not warm in the slightest. I'm covered with BG Homecare so called them out and the engineer said there was a build up of sludge in the pipes, he used a magnet thing to determine this. He also said it will cost me around £600 to flush the system out and clear the sludge. Surely if there was a build up of sludge then the flow would be affected and not the temperature of the water? I was initially thinking the thermostat on the boiler but I wasn't home when he called and you know what wifes are like trying to remember technical stuff.

If it's simply a case of flushing out the system, I'm sure I could do that myself without using any power flushing equipment. Would it be a case of closing off the water, opening the drain outside and letting it empty, open mains water supply again and let it flush around for a while, leaving the drain open?

I don't have a combi boiler, it's a gravity fed hot water system, if this makes any difference.

Thanks for any help, its greatly appreciated and hopefully will save be a few bucks.

Thanks
Glen

 

[secret squirrel]

The flow would not be affected if there is sludge in the system. The coil on the inside of the cylinder is how the hot water is heated up, £600 is far too much to power flush the average system IMO, sounds like you've got another problem though. Have you got a 2x 2port or a 3 port valve. Dodgy thermostat, time clock, valve.....

I would ask a local plumber to come in and have a look. With your (not wishing to be rude) limited knowledge on your system I would pay someone to come in and do it for you. If you could powerflush a system using cold mains water on its own we would not spend huge amounts of money on power flushing machines and chemicals.

Sometimes it pays to pay a professional.

 

[glennybee]

Thanks for the prompt reply secret squirrel.

I have drained the system before when I installed new basin and bath taps, this was over a year ago though so shouldn't be related to the problem. Of course, as you say, it may require more than a basic cold water flush.

I take you're comments on board though and no offence is taken with regards to my knowledge lol.

Not sure about the valve, I've attached two pics of the pipework around my boiler. I also have an immersion heater upstairs which is stone cold.

Thanks
Glen

 

[secret squirrel]

When you drain the system to change the bath taps you are not draining the system! all you are doing is draining the cold water storage tank, the larger of the two in the loft. There should be a small tank in the loft this is part of the heating system.

Silver valve to the left of the pump, from the picture it only has 2 pipes, have you got another one of these valves in your airing cupboard or somewhere else.....

 

[leelister6]

Turn your hot water on at the timer and see if the pipes going into and out of the side of the cylinder are getting warm. There should be a 3 port valve near the cylinder and there is usually a little lever on the 3 port valve which manually opens it. If the pipes start getting hot when you manually open the valve, it is probably the valve head that needs replacing. Also, has the fuse blown on the immersion? If the fuse is ok then the immersion is bust. I wouldn't recommend you change the immersion unless you are confident and have the correct tools or you may end up needing a new cylinder *sharp intake of breath* "It's gonna cost you Squire!"

 

[glennybee]

There doesn't appear to be another valve near the cylinder, just the one.

Further development...my wife turned on the central heating today and the hot water appears to be heating up, the pipes around the cylinder are getting warm and the water's warm, not hot but I guess it's still heating up. The same thing happened last week, no hot water, turn GSH on and hot water hot again.

 

[secret squirrel]

Sounds like you have a knackered valve, thats the silver thingy...... but really need to have a look at your system to work it all out....... the valve should have have 3 pipes but can only see the two..

 

[stevetheplumber]

definately get a second opinion very unusual for sludge to cause your problems unless your heating is also sluggish
just looked closer at the pictures it appears to be gravity hot water check that the header tank in the loft is full of water and the ballvalve works as lack water in system will show first on hot water

 

[stokecity]

i guess its probably a little to early for u to of had ur heating on yet? so if u havnt then put it on and have a good feel of ur pipework and rads as it is the heating pipework that heats ur water so if ur rads are cold at bottom etc then it is sludged, if this is the case then go to a local plumber as powerflushing isnt covered on ur contract so u will have to pay and a local plumber will be alot cheaper but get a second opinion

 

[Gray0689]

definately get a second opinion very unusual for sludge to cause your problems unless your heating is also sluggish
just looked closer at the pictures it appears to be gravity hot water check that the header tank in the loft is full of water and the ballvalve works as lack water in system will show first on hot water

I agree looks gravity hot water could and to be fair it could be sludge slowing everything that's why your only getting hot water when pump for heating going but as said we can not really see much from a few pics just guess work get a good local plumber out to take a look

 

[secret squirrel]

I thought gravity hot water but if this is the case why would you need a zone valve, surely the heating would be controlled on the pump?

the heating would only work when the hot water was on?

not the other way round?

 

[glennybee]

Thank you very much for all your advice folks.

After reading a few other threads, would it be safe to assume a full flushing shouldn't cost more than about £300 or am I wrong there?

Thanks again

 

[stevetheplumber]

I thought gravity hot water but if this is the case why would you need a zone valve, surely the heating would be controlled on the pump?

the heating would only work when the hot water was on?

not the other way round?

My guess would be the heating was creeping so the put on a mv

 

[stevetheplumber]

id say definatly not enough water in system when the pumps on it moves a bit but not on gravity have you checked the tank?

 

[secret squirrel]

Thank you very much for all your advice folks.

After reading a few other threads, would it be safe to assume a full flushing shouldn't cost more than about £300 or am I wrong there?

Thanks again

Depends on how many rads on system etc. and also what chemicals are used. You need to get someone in and have a look for you.