No central heating when turned on via clock.

Every year about this time as the weather changes we notice our heating and radiators stop warming up until we have had a visit by the plumber.

System we have 2 of us, 3 storey townhouse Boiler (Potterton Suprima 60) on Ground Floor and Gledhill BoilerMate 2000 Tank in 2nd floor airing cupboard

How water and pressure of hot water has been good all year no issues including now as writing the post and since the weather hasnt been too cold we havent had the need of using and heating up the whole house.

Ive adjusted the clock and setup the times as and when i need the head on but no heat is going to any of the rads in the property. Not even warm im not heating the noises of the crinkly metallic noise you sometimes get. The pipes are hot to touch from the return and flow on the boilermate and the pumps are also good as these were replaced recently.

All i can think of are the valves or the rads need bleeding ive not done this yet but have also heard when early in morning at some points in the bathroom rad can hear shaking rattling knock noise why would this be its not loud. Maybe need balancing?

The three pumps on the front are grundfos and have been replaced recently. When touched they are hot to touch and the pipes are too.

Hot water is fine and pressure is good. I opened all of their thermostats on the rads but still nothing going into them the feed and return pipes are not warm either. We have homeserve who are due to come out. We do t really touch much on the boiler mate we only use it for calling for the heating. From what the led status says it's initiating the call but I don't hear the typical rads ticking and warming up when it should reach the start time.

Appears the middle pump has failed again weirdly even though it was replaced about a year ago. When inspected by Homeserve engineer he mentioned its not spinning.

He wasn't that familiar with the BM system so mentioned his manager has to come with it. Next week drain the system to replace parts and and fit new isolation and worst case he mentioned he may have problem re filling it. Is there anything I need to know