On the plant floor, an Amsler blow molder running stretch blow molding can’t tolerate uneven preform heating. When the heating tunnel’s thermal profile drifts, you end up with hazy PET bottles, brittle bases, or wall thickness that’s all over the place. The IR radiator lamp is where heat, timing, and repeatability have to line up. Control is what matters, not just wattage. We spec an Amsler-matched IR radiator lamp with short-wave quartz emitters, so response is fast and output stays steady. Power is sized to the machine’s heating zone—matched to the OEM’s power curve—so the lamp follows your existing temperature setpoints without overshoot. You get a clean, repeatable temperature rise across the preform, with controlled heat penetration from neck to shoulder. In practice, the heating profile behaves predictably run-to-run, whether you’re staying on Amsler or converting the line with a compatible retrofit. Here’s why it works: it restores the heating behavior the Amsler blow molder was designed to run. Matching power properly keeps the lamp from fighting the controller, which cuts current spikes and settles the heating tunnel. That means fewer rejects, steadier cycle times, and less scrap from off-spec bottles. Energy use drops because the lamp hits setpoint quickly and holds it without chasing fluctuations. Lamp life extends too, since filament stress stays under control. Before you swap, verify voltage, connector type (often R7s), and mounting dimensions. Make sure lamp length and focal distance match the heating tunnel geometry—otherwise you’ll get uneven hot spots. **Pair the lamp with the correct reflector to keep heat distribution even.**If you don’t, preform heating turns into a guessing game. Schedule the replacement during planned downtime, and align the lamp, reflector, and sensor calibration. That’s how you keep the thermal profile intact.