No heat after engine swap

[CooperClutch]

Hello all. I just completed an engine / trans replacement on my 2005 Cooper S and now I cannot get any heat in the passenger compartment. I've triple checked all connections, the thermostat is working perfectly, I've tried to ensure that there isn't any air in the system (how do I know for sure?). Nothing got in the hoses 9as far as I know). All ideas are appreciated.

Thanks!!

[mab01uk]

Almost certainly an airlock in heater matrix if all was well before. Some bleeding tips here:
Solving MINI Cooling Problems.......... - Forums