2001 escort van heater very poor ?

check heater hoses to see if both are hot,if so then it could be heater flap either not operating with control knob or it wants adjusting[sometimes gets kicked off as its on r/h side of pass footwell just behind fascia!] if only one warm/hot then it could be blocked matrix.if both cold then either thermostat stuck open or water not flowing correctly.

k
December 2010