So I just did the clutch on my truck. When I started it up the next morning I noticed it only blows cold air. Is there anything I could have massed up while doing the clutch that could affect the heater or is this just a freak coincedence?

 

Did you have heat prior to doing clutch?

Start by checking basics. Heater mixer valve is controller cable connected and moving.

Is blower moving air?

Whats coolant level?

Did you drain coolant? open system?