BGMVSP-23 Actuator Problem

[dmilbank]

Can anyone please advise on a recent problem with my actuator. When my heating was switch on for the first cold spell this winter, there was a loud clunking noise vibrating through the system. When I checked the sound source, I noticed that the Actuator had been dislodged. As I attempted to slot it back in to place I noticed that both of the two plastic guides had lost a thin piece of plastic (2mm thick) which were still in the locating points in the pipework. these were removed easily and the A slotted back securely without them. The system then switched on and worked perfectly. Now when the timer switches on the system, the clunking has returned! The A seems to be well seated, but as it tries to switch over from the W position through M to H the indicator springs back with a loud clunk. I don't know exactly what I do, but by just gently pushing in the lever at the back of the unit as it moves across in time with the indicator, the system switches to heating and all works well. Does this suggest I just need to purchase a new Actuator or is there possibly something else causing it to malfunction?

 

[nickso]

switch off the power open it up and check the motor is secured to the body, and the plastic guide for the cam is not broken. Also check both return springs are in place, the spring posts snap easily on early models. Might be worth checking the spindle on the brass body moves easily, they can get sticky making it difficult for the motor to turn it, it only moves 20-30 degrees but should be easy enough with your fingers.

 

[dmilbank]

Thank you nickso,
I took off the cover and a small spring and piece of plastic post fell out!

Can I still use the unit whilst I get a replacement. Am I right in assuming that the lever to the back of the unit is a manual override?

 

[dmilbank]

I've read that I can replace the BGMVSP-23 with a Drayton MA1 actuator without having to worry about different wiring.
Problem is there are two models shown on Screwfix, both shown as MA1.
The 1st one is described as a Drayton Mid Position Valve Actuator & on the picture of this unit is the actuator code MA1 & priced at £57.99.
The other one is descibed as a 3 port motorised Valve, model no. MA1 679-3. at £73.99. Advise on which one will do would be very welcome.