Systemate 2000 - recurring fault

The Systemate 2000 is five years old and has a recurring fault: it heats up the controlling radiator of the central heating sytem although the hall thermostat is set to zero and the heating is in effect shut down. The controlling radiator is also situated in the hall and is without a thermostatic valve so cannot be adjusted.

In April this year our BG engineer replaced the 'non-return valve' in the Systemate and up to last week the controlling radiator was cold - but now it is heating up again. This has been the pattern for the three years.

Is this an inherent fault with the Systemate 2000 product? Anyone out there with a similar problem?

Hi leopold-patrick,

You're lucky it's just one radiator. When the NRV begins to stick open there is potential for ALL the rads at the same level or higher than the Systemate to heat up!

I've seen this several times on the Systemate 2000 and Gledhill would have said it was caused by incorrect cleansing of the water on commissioning and/or lack of good quality corrosion inhibitor, and they'd have a point. But the design of the NRV is cheap and prone to sticking in my experience so yes, a design flaw too in my opinion.

Are you sure the BG bloke fitted a new one and didn't just clean up the old one and re-fit it?

Best solution is to fit a decent quality brass NRV to stop this reverse circulation. Second best (and cheapest) solution is to take one of the rad valve blind caps off and close the rad with a pair of pliers during the warm weather. No harm will result.

Cheers, Mike

Hi Mike

Thanks for your reply - guess a power flush of the heating system will be suggested by BG.

Do not know whether a new NRV was fitted - however I know there was some delay in obtaining the part. Shall make a point of a good quality brass NRV as you suggested.

Will let you know what transpires.

Cheers and thanks for advice.

leopold-patrick

Hi Mike

Have decided to take your advice regarding the controlling rad - removed one of the blind caps and closed the valve as you suggested.

Hope I remember to open it when the weather changes !

regards

leopol-patrick