faulty honeywell valve V4073?

[Pb100]

When my central heating is on but with hot water only selected the radiators have started to get hot as well. When this is happening the Honeywell mid position valve (V4073) makes a quite loud clicking sound.
When the heating is selected only the radiators get hot not the water and no noises from valve.
Any ideas?

 

[tincup]

Hi


Is the lever on the v4073 moving back and forth slightly?

 

[spraggo]

The noise is due to the gear teeth being worn in the midi valve, the head of the valve will need to be replaced with new. However, this fault is usually caused by the valve stem being hard to turn so to be sure I would change the complete valve

 

[Pb100]

Could not see or feel any movement on lever, just get noise “tick tick pause tick tick pause tick tick “