Replace central heating or not

[serd]

I have approx a 26 yr old house. I moved in about 4 years back. For two years I have had a radiator burst. ( the same one 3 times now). Its the one in the bathroom which I think is connected to the storage tank hence is hot all the time. Also most of the radiators in the house only heat at the top and are cold at the bottom. The plumber who repaired the radiator burst for me said that the system had all corroded from inside as the first time he drained the system ( also with the burst radiator) the water was orange-brown in colour.This time when the radiator had leaked its now running clear water.Also the overhead overflow tank had real dirty water in it. My pipes on the ground floor are buried under concrete flooring. Few months back I got a few quotes

£2500 from british gas who would replace just boiler and power flush system.

£3500 from UK-central heating in Manchester who would remove the current system replace it with a combi boiler and replace all the pipe work (leave the original pipework buried underground) And install all new radiators

My question is should i just get the system powerflushed (as no problem with boiler and replace all the radiators
or
Replace everything
or
Replace boiler and powerflush the system.

Obviously with pipes being under concrete I am a bit worried if they are corroded and during power flush they make leak and that could be disastrous

Also does anyone know of UK-central heating or recommend me a company in south manchester who would do a good job

 

[yonmons]

Obviously with pipes being under concrete I am a bit worried if they are corroded and during power flush they make leak and that could be disastrous

I think you have answered your own question with that line....Spending all that money, I think you have to go the extra mile and replace those buried pipes. For peace of mind if for nothing else. I know it hurts to spend on a heating system. I have just had to replace a boiler less than 3 years old installed by british gas, on their bad advice. Ho Hum.....

 

[ChrisR]

The pipes don't corrode with the radiators, only if the salts from the concrete has got to them, or there was flux left in at installation - but that would have stopped by now. It would perhaps doing a little excavating to see how well the job was done - it tends to be worst where the pipes go into the floor.

Orange water is an alarm signal. It means that rapid corrosion is currently happening. The slower-formed oxides are black/brown. Only way that arises is through bad system design, ie causing pumping-over (from the vent onto the header tank) or sucking air. It can be due to sludge blocking a pipe though. But get the system design checked.

Get some more quotes to isolate the cost of repiping.

 

[pud]

Have to agree with ChrisR regarding the pipe corrosion, I had a job, a house sounding similar to your's, in Bramhall/Cheadle Hulme area, the elderly couple had a few bursts with pipes buried in concrete, to cut along story short we had to run new piping (skirting and suface mounted and droppers from the upstairs piping circuit) to replace all the sunken pipework.Non of the copper pipes were protected when set in the concrete, hence pipes corroded.
Not forgetting the gas supply to boiler, fire and cooker! Unfortunately this had to be ran at low level outside the property.If your system is that old would recommend changing everything in one go, piece of mind for the future though! good luck

 

[PEDANTICVINDICTIVEMAN]

Yea do the lot, if BG cause a leak powerflushing on your old buried pipes they will probably want £5500.00 to do what the other firm want £3500.00 to do, do it right and sleep at night.

 

[serd]

Thanks for all the advice. I got a plumber to come out to isolate one of the radiators and he drained it the water was black .He told me that the pipes are copper and shouldnt have rusted also the pipes buried under the concrete are covered with a plastic sleeve.
The latest advice was to clean the system change the boiler and change the radiators. The first floor pipes are under chipboard whichI believe shall all have to be replced if I touched it and the ground floor under concrete.

I have been asked to leave them alone as they are unlikely to rust.( only rads rust I have been told),

Also after changing the rads and the boiler if I get the BG central heating cover it should keep me protected including the pipework

Does this sound like a good idea or should I definately change the pipes

 

[Bahco]

If the pipes are buried under concrete then it is likely that they will be full of sludge which will probably take lots of flushing to dislodge, as they will be below the lowest drain point
This will circulate around your new boiler and pipework and won't do it much good.
If you are spending good money on a new system don't spoil the ship for a happorth of tar and renew the lot