NuTone QTXEN110S — Humidity Sensing Fan Installation & Operating Guide

Installation, operation, and maintenance guide for the NuTone/Broan-NuTone QTXEN110S humidity-sensing ventilation fan.

Safety Warnings

• Use only as intended by the manufacturer
• Before servicing or cleaning, switch off power at the service panel and lock or tag the disconnect to prevent accidental power-up
• Installation and electrical wiring must be done by qualified persons in accordance with all applicable codes, including fire-rated construction codes
• Ensure sufficient combustion air for fuel-burning equipment to prevent backdrafting
• Take care not to damage electrical wiring or hidden utilities when cutting/drilling into walls or ceilings
• Ducted fans must always be vented to the outdoors
• Acceptable for use over a tub or shower only when connected to a GFCI-protected branch circuit
• This unit must be grounded
• For general ventilating use only — do not exhaust hazardous or explosive materials/vapors
• Designed for flat-ceiling installation only — do not mount in a wall
• Keep drywall spray and construction dust off the power unit to avoid motor bearing damage and unbalanced impellers

Operation

The humidity control and fan can be operated separately using a 1- or 2-function wall control (do not use a dimmer switch). The fan responds to (a) rapid-to-moderate humidity increases and (b) humidity above a 50%–80% relative humidity set-point, both adjustable via the "HUMIDITY" control. A status indicator (visible only from directly in front) blinks normally 5 seconds on/off; if it blinks rapidly for 5 seconds then shuts off, check the sensor connections on the grille and fan housing.

Manual On With Timed Off (Odor/Vapor Control)

1. Turn the wall switch on for more than 1 second (if already on, skip to step 2)
2. Switch off for less than 1 second
3. Switch back on — the fan will run for the timer-set period

Timer Adjustment

User-adjustable from 5 to 60 minutes; factory set to 20 minutes. To adjust: disconnect power at the service panel, locate the "MINUTES" screwdriver slot through the grille, and carefully rotate to the desired setting with a small flat-blade screwdriver. Restore power and verify by cycling the switch or triggering a humidity source.

Humidity Adjustment

Factory-set for most shower applications. For tub areas or dampness control, decrease toward 50% RH; if the fan responds too often to environmental changes, adjust toward 80% RH. Adjust via the "HUMIDITY" screwdriver slot through the grille (power off first), then verify by running a humidity source until the fan activates.

Planning the Installation

• Locate the unit above or within 5 feet of the shower head (GFCI-protected circuit required)
• Keep away from heating/cooling sources that affect humidity readings
• Avoid locating near a window — the unit may respond to outdoor humidity
• Must be installed in the ceiling to properly sense moisture, on flat ceilings up to 12 feet high
• Choose a location with the shortest possible duct run and fewest elbows
• Do not operate this unit with a speed control — it will damage the sensor

The housing can be mounted to joists, I-joists, or anywhere between framing using the included sliding hanger bars (span up to 24"). For I-joist mounting, use the included spacers between the highest mounting-flange hole and the joist.

Installation Steps

1. Mount the housing to the joist/I-joist or between framing members using hanger bars, secured with the included nails or screws through the mounting flange holes
2. Attach the damper/duct connector — snap it onto the housing flush with the top, ensuring the damper flap falls closed
3. Install 6-inch round ductwork from the damper/duct connector to a roof cap or wall cap; tape all connections airtight
4. Connect electrical wiring: run 120 VAC house wiring to the location and secure it to the wiring plate with a UL-approved connector per the wiring diagrams (two wiring options are supported — simple ON/OFF switch, or a 2-function ON/OFF + AUTO/OFF control such as Model 68W, sold separately)
5. Finish the ceiling material, cutting out around the housing
6. Plug the wiring into the proper receptacles
7. Attach the grille to the housing by squeezing the grille springs and inserting them into the slots on each side
8. Push the grille flush against the ceiling

Cleaning & Maintenance

For quiet, efficient operation and long life, lower or remove the grille periodically and vacuum the interior with a dusting brush attachment. The motor is permanently lubricated and never needs oiling — if bearings become noisy, replace the motor/blower wheel assembly.

Sensor Cleaning

1. Disconnect power at the service entrance
2. Remove the grille; clean the sensor and grille with a dry dustcloth, clean toothbrush, or light vacuuming — do not use abrasive cloth, steel wool pads, or scouring powders
3. Never use cleaning sprays, solvents, or water on or near the sensor

Service Parts

Replacement parts can be ordered at www.nutone.com. Order by "Part No.," not "Key No."

Warranty

NuTone provides a three (3) year limited warranty from the original purchase date covering defects in materials or workmanship (excludes fluorescent lamp starters and tubes). Excludes normal maintenance, misuse, negligence, accident, improper maintenance/repair, or faulty installation. NuTone's sole obligation is repair or replacement at its option; incidental and consequential damages are excluded (subject to state law). For warranty service, notify NuTone with model number, part ID, defect description, and proof of purchase date.

Manufacturer: Broan-NuTone LLC, Hartford, Wisconsin · www.nutone.com · 888-336-3948