Technical content reviewed November 12, 2026 · Tillman & Associates
What the dual-lamp arrangement provides
DLN[X] uses two single-ended lamps projecting from an enclosure mounted outside the HVAC equipment. The manufacturer identifies indoor and outdoor ducts, plenums and rooftop units as application starting points. This places fixture service access outside the treatment space.
Two lamps can offer a useful arrangement where the equipment geometry calls for it, but lamp count is not a coverage calculation. Send the coil-face dimensions and proposed mounting location so the layout can be reviewed.
DLNX versus SLNX and DEX
SLN[X] uses one projecting lamp in a NEMA 4 enclosure. DLN[X] uses two. DE[X] describes a double-ended lamp arrangement mounted internally; it does not mean the same thing as a dual-lamp DLN[X]. Compare the installation and service paths before comparing wattage.
A single longer lamp and two shorter lamps are not automatically equivalent. Location, shadowing and the treatment objective matter. A layout for stationary coil surfaces should not automatically receive an airborne reduction claim.
Lamp selection and operating limits
The shared SLNX/DLNX installation manual, revision E (November 2025), limits DLNX lamps to 12–30 inches and specifies 800 mA, T5, four-pin single-ended lamps. It states that the DLNX fixture will not operate with one lamp missing or failed. Confirm the exact lamp and fixture identification for replacement work.
That manual gives a 150°F maximum lamp operating temperature. Broader ranges in a datasheet should not be applied to every component. Supply the actual operating conditions for review rather than assuming the fixture rating establishes treatment performance.
Installation and maintenance planning
Allow room outside the equipment to remove both lamps, and identify nearby insulation, wiring and other UV-sensitive materials. The installation must address access interlocks, shielding and light leakage. UV-C can injure eyes and skin; disconnect power before access and follow the complete manual.
A monitoring signal helps identify operating status. It is not a measurement of UV dose at every point across a coil or through a duct. Include the desired monitoring and building-controls connection in the inquiry.
What to send Tillman
- Treatment goal and any specified performance target
- Coil/duct dimensions, airflow, temperature and humidity
- Indoor/outdoor exposure, mounting position and service clearance
- Supply voltage, control signals, access doors and interlocks
- For replacements: fixture label, both lamp numbers, connector photos and quantity
Common questions
Does dual-lamp mean double-ended?
No. DLNX has two single-ended lamps. DEX is a different arrangement with a connection at each end of a lamp.
Can the fixture run with only one lamp?
The shared installation manual states that DLNX will not operate if one lamp is absent or fails. Verify the assembly and follow its troubleshooting instructions.
Can we choose it from duct width alone?
No. Include the treatment objective, airflow and proposed mounting geometry as well as dimensions.
Technical references
- DLN[X] datasheet · PDF ↗
Datasheet · 2 pages
- DLN[X] installation instructions · PDF ↗
Manual · 7 pages
- DLN[X] specification · PDF ↗
Specification · 1 pages
Confirm the revision and exact assembly before ordering. This guide supports selection and parts inquiries; use the supplied installation instructions for the work.