Jamming Honeywell valve?

I changed a two port valve head with replacement 40003916 just 13 months ago. Recently, I've found our Baxi Solo HE boiler stops burning after an hour or so, leaving just one green light, which eventually lights the other green +blinking red. Checking live feeds, the grey wire confirms being OK as does the orange one. The valve appears to be opening, however, I noticed that the leaver at the bottom, fails to move when the valve is either opening or returning on the spring. Could this be the boiler problem?
Thanks

From your description, the motorised valve appears to be acting as it should. The lever doesn't move during normal use. It's only there to manually open the valve when the heating system is initially being filled with water, or drained down.

When the valve is opened by the heating controls, the lever can be moved manually but there will be little or no resistance felt when doing so. If the valve is closed, then some resistance will be felt as it is forced open.

Hopefully someone who is familiar with your model of boiler and knows what the boiler indicator lights are telling you will be along to advise shortly.

Well, if the LED lights are as you say - far right green (mains) on > middle green on (burner on)>left red flashing (lockout) then that indicates a PCB fault.

That being said if you reset and the boiler comes back and runs again for an hour then that may be misleading, unless the PCB has an intermittent fault.

Many thanks Rob. Boiler's due for a service so will get my regular guy to check. Just thought it might've been a loose wire point I could handle.

Thanks again - Roger