Heater not working correctly since blown head gasket changed.
The coolant system seems to be working ok. Temperature reading 90°,
radiator hot, inlet and outlet pipes to heater matrix hot, outlet pipe
to thermostat hot, then top hose from thermostat to radiator suddenly
changes from cold to hot which must indicate thermostat operating
correctly, water expanding in radiator which indicates pressure ok.
Only warm air is expelled through the screen and dashboard vents, the
lower vents in the footwell are virtually cold.
I have found two "valves", one on the thermostat housing and the other
just above it (5mm socket head) which I have undone hoping to bleed the
system; only water came out, no air was apparent.
Any suggestions of what to try next please?