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I have a "one-pipe" heating system and want a new high efficiency combination boiler.

My preferred Installer has said that the system should be converted to a "two-pipe" design.

Why is this? What will happen if I don't convert? can I damage my new boiler? and he's saying cost is about £3800. Does this sound expensive?

The property is a 3 bed, 6 radiator bungalow.

Thanks in anticipation.

Grahame.

The one-pipe system will be fine with a combi boiler, but unlike the boiler they're not very efficient.

Are the radiators and pipework in decent condition ? maybe this is what the installer is referring to.

htg

Hi,

I put a combi on a one pipe system - never again!!

It doesn't heat the house to any satisfactory degree,

I changed it to a two pipe -- perfect - roasting

But £3800 WTF

[quote="bluegrahame"]I have a "one-pipe" heating system and want a new high efficiency combination boiler.

My preferred Installer has said that the system should be converted to a "two-pipe" design.

Why is this? What will happen if I don't convert? can I damage my new boiler? and he's saying cost is about £3800. Does this sound expensive?

The property is a 3 bed, 6 radiator bungalow.

Thanks in anticipation.

Grahame.[/quote]
if the pipework is in good order and the system is power flushed [ most manufacturers will invalidate the warranty if this is not done . allow £500]then there should be no problem as long as the return is kept below 50c

[/quote]
if the pipework is in good order and the system is power flushed [ most manufacturers will invalidate the warranty if this is not done . allow £500]then there should be no problem as long as the return is kept below 50c[/quote]


most manufacturers ask for the system to be cleaned not power flushed and the warranty will still be ok

How do you powerflush a one pipe system? Doesnt the water just bypass the radiators?