ch not working

We have 2 x circulating and 2 x shunt pumps (for redundancy - we live in an old council building). Please could you advise the best way to find out if a pump is rotating or not? Any of the four pumps running will vibrate the others, so vibration doesn't help. I tried this little compass device...

Long shot i know but im having a problem with a Biasi m90 32. I can only have either ch or hot water and I only achive that by moving the wires on the diverter, Ive had the diverter changed and the the wiring to the diverter changed and the circuit board changed, any ideas on what it may be?

Hi, I have been through the forum and tried to find similar issue, but its always complex. My boiler failed and after engineer's visit he advised that boiler needs replacing as the fixing is not economical! What an advise! He wasn't sure what is the issue and advised so many different 'maybe'...