Hello,

Our gas boiler is 8 years old. It powers the radiators and hot water for the house. For a few years now the water has begun to run cold for short periods – noticeable during showers, though it doesn’t seem to effect hot water in the kitchen.

The shower is about 3m higher than the boiler, the kitchen about 3 m below. Will that have an effect?

Any Ideas?
Is 8 years old for a gas boiler?
The system is controlled by a central thermostat on the wall as opposed to thermostats on each rad. Is that out dated now?
How much to change the boiler and install thermostats on each rad? 6 rads in the house.

Any advice please?!
Cheers!

If it’s a combi boiler it sounds as though you should check the pressure and turn that tap which refills it with water. When they’re running empty they perform like that.

When was it last serviced?

doing rad stats is fairly cheap if they’re draining the system and flushing it for a new boiler anyway but you’d still keep the central one too.

I’d allow £2k for a new boiler and associated work.

One thing to check is the size of the gas pipe – if it’s 15mm it may need to be changed to a 22mm supply.

Flow sensor maybe. They can gum up a bit which can make it intermittent. Mine pops open with the removal of a circlip.

Pressure – that we must check!
I’ll read up on the flow sensor. That is a potential as the problem has been getting worse and the “outages” have been getting longer.

If it is a combi and there is plenty hot water at all other taps, I’d be looking at the shower. No need to replace an 8 yr old boiler, I would have trv’s fitted though.

What he said about the shower.

Personally i wouldnt be mch fussed with trvs but would fit a programble 7 day wireless stat.

Most stats are in the hall and about as much use as a toaster for the job.

Trail Rat and Supreme Bean – I think you’re onto something. Seems so obvious but it may be the shower mixer unit. It could be as simple as the tap washer being a bit dodgy.

I’ll look into it.

Cheers all!