Biasi 24s diverter valve not working

[percivjr]

This Biasi 24s has been switched off for 18 months during renovation work. Not sure if it ever worked properly!

Upon switching on again, the CH worked fine but the DHW was cycling on and off every minute or two. I removed the secondary heat exchanger - the primary side had some crud in it but the DHW side was fairly clean. I flushed out with a hose and cleaned with spirits of salt. Both halves seemed to be flowing freely.

Having refitted the shiny heat exchanger, the diverter valve no longer operates. Even though the diaphragm looked OK, I replaced it anyway.

The main circuit flow switch operates in in CH mode and CH is still working OK.

Any ideas what the problem might be, please?

Incidentally, I did remove the DHW filter/flow limiter. Maybe I didn't put those back properly as I see that the two pipes to the diaphragm emanate from this proximity?

 

[Agile]

Did you remove the gas valve to get at the inlet filter?

Don't you think that a professional check/service would be justified before the property is occupied again?

Tony

 

[percivjr]

No, it's possible to remove the inlet filter without touching the gas valve.

I note your comments regarding a check, etc. But want to get it working first.

Going to check the inlet venturi next. Maybe I damaged it or it disintegrated on replacement.

 

[percivjr]

Going to check the inlet venturi next

I removed the inlet filter again, all seemed OK. I unscrewed the venturi to reveal the flow limiter, put it all back together again and it's working fine.

 

[Agile]

Are you sure that you have the correct model?

How many knobs does it have?

Model number on data plate?

Tony