Is hot water running through heater pipes? Feel the small dia pipes running from the engine through the bulkhead to the heater. One should be slightly hotter than the other. If they're both cold then the heater is blocked and requires flushing.
The heater temperature controls may not be working. operate the control and check that something is happening to the levers on the heater unit under the dash.
Dann
September 2007
if only just happened check water level urgently. If low this will be the reason. If its been getting worse (ie colder) over a period of time then the matrix itself is/has become blocked. Could try a cleaner for water circuit from halfords etc
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