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Q: Heater is not working. Replaced thermostat. Both hoses at firewall are cold. Maybe replace core? 2000 Ford F-250 5.4L

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2000 F-250 5.4L Heater is not working. Replaced thermostat. Both hoses at firewall are cold. Replace heater core? Controls are working. Engine temp is normal. Blows cold air only.

My car has 185000 miles.
My car has an automatic transmission.

Hi - most likely, either the heater control valve is not functioning properly, or the heater core itself is clogged enough to restrict flow. I would recommend a heater inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

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