Glow worm space saver

[paul_harry1]

Hi currently have a glowworm space saver boiler which is probably around 30 years old. Everything fires up well but recently had issues where when the heating system is on. It sounds like every time the water is being circulated the pipes around the water cylinder are making a grumbling noise making it sound like it's about to take off. Once the heating as been on for abit it seems to make the noise every few minutes or so. It builds up with a grumbling noise to pretty shaking the house for about 30 seconds and then stops again for a few minutes. The heating heats radiators upstairs but doesn't seem to be heating radiators downstairs. Just wondering if anyone knows what the likely cause of the issue is.

 

[Mister Banks]

Could be a faulty zone valve.

 

[cross thread]

Poor circulation or blocked cold feed

 

[oilhead]

Is the pump as old as the boiler?