Honeywell F1-9318 - Buzzing Noise

[BF]

During the early hours of today, this item was making a loud buzzing noise, which eventually stopped.

I don't know what it is or what it does, and I don't know if the noise stopping was indicative of it now being broken.

What does this do and if it is broken, how will this affect my heating and hot water?

Thanks for your help.

 

[jj4091]

Looks like it is a motorised valve.One of them ( heat or HW ) probably won't be available. You might be able to operate it manually until you get it replaced if it is faulty

 

[BF]

Looks like it is a motorised valve.One of them ( heat or HW ) probably won't be available. You might be able to operate it manually until you get it replaced if it is faulty

Thanks for your reply.
On closer inspection, there are two of these valves, the other is a Honeywell F3-9601.

The affected one is in the "Auto" position.

What do they do and if it's now not working, how will this affect my heating and hot water?

 

[stem]

Motorised valves have a synchronous motor inside. The motor winds opens the valve and when it's open the motor 'stalls' in that position. This means the motor isn't moving now, but remains powered to keep the valve open. As they get old and worn they can buzz but continue to work.

So, if your heating and hot water are still working as they would normally this is likely the case. On the other hand, if the motor is weak and has failed to open the valve then either the hot water, or the central heating won't operate properly.

The valves should be in the 'Auto' position during normal operation. They can be locked in the manual position when the system is initially being filled with water when it has been first installed or drained down for maintenance.

 

[BF]

Motorised valves have a synchronous motor inside. The motor winds opens the valve and when it's open the motor 'stalls' in that position. This means the motor isn't moving now, but remains powered to keep the valve open. As they get old and worn they can buzz but continue to work.

So, if your heating and hot water are still working as they would normally this is likely the case. On the other hand, if the motor is weak and has failed to open the valve then either the hot water, or the central heating won't operate properly.

The valves should be in the 'Auto' position during normal operation. They can be locked in the manual position when the system is initially being filled with water when it has been first installed or drained down for maintenance.

Many thanks.
It was in the “Auto” position when I last looked.
Both of them have been in operation for many years so maybe time to be replaced.