08 1.6 Cooper - Heater blowing cold only

[magpies]

Just used the car for the first time in a month and the heater for the first time in 6 months. Only blowing cold after 3 miles. Coolant level a little low (5mm below 'low' level) and now topped up. No 'hot engine / water leak' smell.

[steve-5snwi]

Check to see if the cable has come off the heater control, you need to look in the driverside footwell and behind the center console.