Annoying noise in heating when Thermostat switches off

[paulfromswindon]

Hi,

I have a Glow-worm Fuelsaver Mk2 pumped system with about 10 rads and an annoying problem. The system would be about 16 years old, serviced once a year for the past four years, cannot comment before that, but probably not.

Whenever the thermostat cuts out, or the timer shuts the systems down, there is an annoying noise that goes through the system. It only lasts a second, and the best description of the sound is as follows: If you imagine having a tin full of screws, give it one quick shake, and that is what it sounds like. It's a kind of quietish, very brief rattle.

My neigbour also has the same problem, so I would imaging that it's a feature of all the houses in our street.

Any idea what the likely cause maybe? I drained the system two years ago to change a rad, the water coming out was quite clean, and I put Fernox Inhibitor in when I refilled the system.

Thanks for your help,

Paul

 

[ChrisR]

Most Likely contenders is a worn pump rattling a bit.

 

[paulfromswindon]

Never thought of that - thanks Chris, I'll look into it..

Cheers

Paul