Refurbish existing CH or change to combi system ?

[pete3933]

Could someone give me some advice on a central heating problem I have .

Will try not to waffle too much , so will keep it simple .

Basically , I have a gravity central heating system with a header tank and cylinder to store the hot water .The boiler on the system is an old glow worm space saver bolier . Anyway , although the heating side of the system works fine , the hot water side of it's not the best .For the hot water to kick in , I need to constantly vent the cylinder . Even then it is hit and miss as to how much it heats up . The motorised valve is broken , but how much this impacts I'm not sure .

Anyway , had someone round to give me a quote for a new valve and to fix a leak on a rad .

He said that the cylinder was in poor shape but could still fit a new valve , but suggested that instead of trying to repair the system as it is ( which may include the cost of a new cylinder ) , it may be worth replacing the old boiler with a new combi boiler . He quoted around £ 1250.00 for the replacement ( A Baxi boiler ) . The bloke seemed pretty straight , so am pondering it at the moment .

So , should I get the old system repaired or just go for a new combi ? Although the old boiler is inefficient copmpared to modern boilers , a work mate a few years ago said I shpuld keep the old glow worm bolier as it'll last a lifetime compared to modern boilers .

I supose there's no absolute correct answer , so any advice would be much appreciated .

Thanks !

 

[dcawkwell]

Firstly you need to check that you have a good flow of cold mains coming
into the house. I hope the guy you had around did this.

You can do this yourself using a 5 ltr oil carton and measuring time to fill.

You need around the 20 litre/minute mark to make a combi a good option.

If you want to keep the existing system that is a good option and involves
doing virtually nothing. Sorting out little problems and getting the
thing working reliably shouldn't present any problem to a competent heating
engineer. I would suggest going to a fully pumped system rather than gravity fed system for the hot water tank. But nothing wrong with
staying as you are.

My advice is stay as you are unless there is a major failure of
one of the boiler parts which might be by the time you retire.
Adding extra features like thermostatic valves to the radiators
wall thermostat and tank thermostat will save money on the existing
system and improve the performance.

You can always upgrade the tank should this fail to an unvented cylinder
and have mains pressure hot water but a much faster delivery rate than
a combi and you have the backup of the immersion heater still. The old
boiler will happily heat it.

 

[pete3933]

Thanks for the reply . Much obliged !

Will get a new motorised valve for a starter and see if this helps the situation . Have also been advised to run a chemical cleaner throught the system as it may be a build up within the pipework.