check the theremostat too,all heaters wont work till the engine has reached its opt teperature,since its the engine that heats the water then the thermostat opens allowing the water to circulate around the engine and heater matrix
mm
October 2011
does the heater work on all numbered settings ?,eg can you hear the fan motor on settings 1 2 3 4 ? if you haven't got all settings then you will have to replace resistor pack . if all speed settings are available then I would suggest checking coolant level ,.also most heaters don't work that efficiently on full nacker if engine has not reached its normal running temperature .
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