"this product was easy to fit however having made this mistake make sure you get two new gate value for each side of the pump as you may find the exsisting values may not come off or break (which did in my case). The self bleeding function is great would recommend setting the pump to drain/bleed model (by putting red dial into the middle setting) prior to switching back on again. After 10 mins the pump stops and the display flashes with two lines and your ready to switch to normal mode. You have two options 3 fixed speeds or any speed up to the max ramping up gradually which reduces radiator noise. Power saving from a standard pump is about a half (my example was 90w to 40w)"