i have a Shurflow pump installed on my system see below
The water in the van tank is 16 degrees thanks to a aquarium heater, hoses and poles are in the house, the pump is still in the van but I will get some fittings to easily remove overnight in future.
If I unscrew the plastic filter cap water comes out of it but nothing is coming through the exit of the pump.
The flow controller is not showing a dead end, and if I push it up to 99 still nothing coming thru.
I have directed the heater in the van at the pump now is there anything else I could try?
Some advice on how to remove airlocks would also be useful as I am sure I have only solved these in the past by trying everything and was not sure what caused it to work each time

i am based in Fakenham Norfolk been -10 here last couple of days, -2 now I am desperate to get out today if I can, have not worked for 2 days due to iced up tank and don't mind working in the cold.
any help will be gratefully received.
Tony