The Real Truth About IP65 Sealing in IR Heaters
You’ll see “IP65” all over spec sheets. It looks great on paper, but here’s the thing: for infrared heaters, the chassis usually isn’t what fails. The real nightmare is where the lead-wire enters the unit. When you’re pushing high wattages, heat doesn’t just go forward. It creeps backward, right toward your electrical connections. That’s where things get messy. Why things actually break Most basic seals just use rubber gaskets. Simple, right? Except in high-heat environments, that rubber hardens. Then it cracks. Once that seal goes, moisture sneaks into the lead-wire housing. It creates a tiny conductive path between the live wire and the grounded chassis. We call these “slow-burns.” Everything seems fine for six months, and then—pop—a dead short trips your breaker and shuts everything down. Doing it the right way A lot of generic heaters just use off-the-shelf glands. We do things differently. We start by stripping the lead-wire and potting it with high-temp silicone. We make sure the silicone expands and contracts at the same rate as the quartz or metal housing. Why? Because when your unit swings from 20°C to 500°C, you don’t want the seal pulling away and leaving a gap. Then there’s the wiring. We use fluorinated polymers for the outer jacket. They don’t melt. They don’t get brittle under constant IR radiation. If you try to use standard PVC, you’ll see the jacket shrink and crack in a matter of weeks. It’s just not built for this. The tricky part Here’s a bit of a catch: if you seal a heater too tight, you build up internal pressure. You can’t just plug every hole like a cork in a bottle. We build in a controlled venting path. It lets the air breathe while keeping the liquids out. One last tip: remember that a tighter seal traps more heat around the terminals. Make sure your wiring gauge is rated for that extra heat inside the junction box. If you don’t, you’re looking at voltage drops and wires that burn out way too soon.