Excavator Heater Blows Cold Air - What Could Be the Problem?

[Gryks Machines]

I recently purchased an excavator, but the heater only blows cold air. I checked the coolant lines and couldn't find any control valves. Has anyone experienced this issue or knows what could be causing it?

 

[Big_Iron]

@Gryks Machines, check whether the engine is actually reaching operating temperature. A thermostat stuck open can keep the coolant too cool for the heater to work properly. If the engine temp looks normal, feel both heater hoses. If one is hot and the other is cool, you could be dealing with a plugged heater core or restricted coolant flow. Also worth checking for air trapped in the cooling system after any recent coolant work. Hopefully it's something simple and not a heater core replacement. Good luck!