International HX Heat & AC Parts

Frequently Asked Questions About International HX Heat & AC Parts

What year models of International HX trucks are these HVAC parts compatible with?

Our International HX heating and air conditioning parts are designed for HX models from 2016 to present. The HX Series includes the HX515, HX520, and HX620 models. Most components are direct replacements for OEM parts, but we recommend verifying your specific OEM and build date when ordering blower motors, evaporator cores, or control modules, as International made minor updates to the HVAC system in 2019 and 2021 model years.

How difficult is it to replace the heater core in an International HX, and what tools are required?

Replacing the heater core in an International HX typically takes 4-6 hours for experienced technicians. You'll need to remove the lower dash panel and disconnect the HVAC box. Required tools include a coolant drain pan, basic hand tools, trim removal tools, and a torque wrench. The most challenging aspect is accessing the mounting bolts behind the center console. We recommend having a second person assist when removing the HVAC box assembly to prevent damage to surrounding components.

Why is my International HX AC system not cooling properly after installing new parts?

The most common issue after parts replacement is improper refrigerant charge or air in the system. International HX trucks use R-134a refrigerant and require 3.5 to 4 pounds depending on your configuration. Ensure the system is properly evacuated before charging. Also verify the cabin air filter isn't clogged, as this is often overlooked. If you replaced the compressor, confirm the clutch gap is set to 0.016-0.031 inches. Many cooling issues stem from electrical problems, so check the pressure switches and control module connections.

What's the difference between OEM and aftermarket blower motors for the International HX?

OEM blower motors typically carry Navistar part numbers and cost 40-60% more than quality aftermarket options. The main differences are bearing quality and motor windings. OEM motors generally last 150,000-200,000 miles, while premium aftermarket motors from manufacturers like Four Seasons or UAC provide similar longevity at lower cost. Aftermarket motors must match the OEM amp draw (typically 25-30 amps on high speed) and mounting configuration. Avoid motors under $125 as they often use inferior bearings that fail within 50,000 miles.

Can I upgrade my manual HVAC controls to automatic climate control on my International HX?

Converting from manual to automatic climate control requires significant modifications and isn't simply plug-and-play. You'll need the automatic control module, additional wiring harness, interior and exterior temperature sensors, and sun load sensor. The BCM (Body Control Module) also requires programming at an International dealer. Total parts cost typically exceeds $1,200, plus 6-8 hours of labor. Most operators find it more cost-effective to repair their existing system rather than attempt this conversion.