Honda 79115-TS8-A02 Heater Core Sub-Assembly

Start by deflating your Civic's air conditioning system if you have it, before moving on with heater core replacement. Remove the cable from the negative terminal of the battery and let all the coolant flow out. At the front of the vehicle, unscrew the bolts holding the air conditioning lines in place, then use the special tools to disconnect the dash end of these lines from the vapor regulator valve (TXV) and disconnect the heater hoses from the heater core. Take off the heater control unit nut under the hood, being careful not to hit the fuel or brake tubes along the way. Start by disconnecting the instrument panel. Then remove the blower motor and power transistor electrical connections. Afterwards, take out the heater/air conditioning assembly bolts, also disconnecting the electrical connections before you can pull it out. Unroll the carpet and disconnect the evaporator drain hose from its mounting point on the firewall. Unscrew and disconnect the blower unit from the heater/air conditioning housing component. Remove the heater duct screw and duct from the passenger side, then take out the heater core cover screws that are connected to the expansion valve cover. First, disconnect any fasteners holding the expansion valve cover, and when present, remove the seal. Afterwards, unscrew the heater pipe bracket screw and loosen brackets. During installation, put the heater cover back on the heating and air conditioning unit while you reconnect the hose connections at the firewall. Finish by joining everything again - plug in the battery, refuel your cooling system, give your AC shop a call to recover, check for leaks, and reload air.