The SL Series SL-4000 from Infratech
4,000 watts of 93%-efficient infrared heat from a 63.5" single-element quartz-tube heater in an anodized aluminum Slimline housing: an average 10' x 10' of coverage from a 8' – 10' mounting height, 240V, 208V, 277V variants, from $1,109, UL & cUL listed, made in Gardena, California, and backed by a 3-year parts warranty.
Choose the SL-Series for pergolas, cabanas, and tight structures where a slim profile matters more than raw output — it's Infratech's narrowest housing, in silver or black.
It is not a furnace substitute — Infratech states these radiant heaters are not a replacement for forced air or ductless heating. It must be hard-wired by a licensed electrician (there is no plug), and the 277V and 480V variants are rated "Commercial Use Only" — do not order those voltages for a home.
Specifications
Keep 18" of clearance at the sides and ends, 36" in front, and 6" behind the heater; wall mounts sit at least 12" below the ceiling angled 30–60° down, and the minimum mounting height is 6' (UL) or 8' (UL/cUL). Power is 240V, 208V, 277V depending on the variant, drawing 16.7 A at 240V / 19.2 A at 208V / 14.4 A at 277V, on a dedicated hard-wired circuit.
SL-4000 vs. its closest Infratech options
Within the Slimline family, the 3,000-watt 63.5" model runs from $1,090 vs from $1,109 here — pick by the area you need to cover.
Features
- Slim anodized-aluminum profile in Silver or Black Slimline Shadow that blends into pergolas, cabanas, and other structures
- 93% efficient, emission-free infrared heat from a single quartz-tube infrared element with a high output safety grid
- Covers an average 10' x 10' area from a 8' – 10' mounting height — up to 12' x 12' in protected spaces
- UL & cUL listed, CE approved, and IPX4 rated — proudly made in Gardena, California
Answers to common questions
Do I need an electrician to install it?
Yes. Every SL Series heater is permanently installed and hard wired by a licensed electrician to NEC and local codes — the housing is drilled and threaded for standard 1/2" conduit, and outdoor installs use components rated IPX4. There is no plug-in option.
Which voltage should I order?
Match the circuit your electrician will run: this model comes in 240V, 208V, 277V versions, and the element must match the supply — a 240V element on 208V supply will warm but not glow or heat properly. The 277V and 480V variants are rated "Commercial Use Only" per the manual — don't order them for a residence.
How much area does it actually heat?
Infratech rates the SL-4024 at 10' x 10' average coverage from a 8' – 10' mounting height — up to 12' x 12' in protected areas, and closer to 8' x 8' in extreme cold or wind. Heating from two sides beats one big heater when you can do it.
Can it stay outside in the rain?
It's all-weather construction, and the manual requires outdoor wiring components with a minimum IPX4 rating — but Infratech recommends hanging it under a roof or weather cover when possible — it will last longer and look better protected from rain and snow.
What controls does it need?
A control or switch is required and every Infratech control is sold separately — from simple on/off and duplex switches to INF regulators, the smart dimmer/switch, and zoned control panels. One caution from the manual: using competitor controls or accessories may void the Infratech warranty.
What’s included, what’s required, and what’s optional?
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Included in the box: 63.5" single-element quartz-tube heater in anodized aluminum housing; 4,000 Watts of 93%-efficient infrared heat; Wall/ceiling mount swivel brackets; UL & cUL listed.
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Required to complete the installation, purchased separately: An Infratech control or switch — every control option is sold separately; A dedicated circuit at your selected voltage, hard-wired in 1/2" conduit by a licensed electrician to NEC and local codes (components rated IPX4 outdoors).
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Optional: Options: Infratech smart and value controls to run it — the heater itself ships complete with its brackets.
Does buying online affect my Infratech warranty?
No — The Torch Guys is 1 of only 5 authorized Infratech online dealers in the United States, so the full 3-year limited parts warranty applies. And we handle it for you: we register your heater with Infratech (which also enrolls you in their Heater Maintenance Program for free replacement end covers) and we file any claim directly with the factory, so you're never chasing paperwork.
