HPA2 Actuator, 4 Wire

As described. Prompt delivery and was instant change like for like. Price was good and now doing it's job perfect.

Straight swap for existing head, just the job.

Awesome delivery speed, and quality of item is legit. I have a S plan system with a megaflo and this will sit on a two port valve body. After scrutinising the wiring diags of both heads, I could see that the 4 wires did the same thing and connected to the same places so a straight swap into my wiring hub. The old Sunvic head although on the surface was functioning correctly was letting voltage through and calling on the boiler even when the CH and HW were both off. I diagnosed the issue by turning off HW and CH on the thermostat (a NEST) and although the CH and the HW valves were closed (correct positions)... The pump was still running and a call for boiler was displayed on the boiler front panel. By removing the switch live (orange) from the valve head into the wiring hub it immediately dropped the demand on the boiler and the pump powered down. Our pump was running mostly 24/7 before and the boiler was firing. Now outside the HW and CW programme its total silence from the boiler cupboard ! Thank You God !

Direct replacement for Sunvic SZ2301. Fits and works as expected. It can be a bit tricky to locate the valve on the actuator so this may be why some say they can't get it to fit. In my case, the valve body was 28mm and the actuator fits correctly. Also available from other online retailers but Amazon price was good and it was delivered same day by 10pm for me.

Purchased to replace a this exact part that has failed after 5 years. Due to it just bolting to the plumbing valve which was still working fine, it made for a strraghtforward 1:1 replacement without having to call out a plumber over Christmas. The new one is almost silent in operation, which threw me a bit when testing! Hopefully this lasts longer than the original.

Direct replacement worked fine. Received the next day. Replacing the motorised head saves the trouble of replacing the whole valve. But make sure the valve is free to turn on and off otherwise a full valve replacement will be needed.

It's a standard product. They don't last forever and you should have a spare in stock. There's no plumbing involved in replacing one, but it does require simple electrical work - at a bout the level of repacing a mains plug.

It’s a brand new actuator at a very reasonable price and it works as it should! What more is there to say?