American Standard ACONT401AN21MA User Manual (English)

Other manuals for American Standard ACONT401AN21MA

Questions and Answers:

K
kristyharveyAug 20, 2025
Why temperature setting will not change on American Standard ACONT401AN21MA Temperature Controller?
- J
  jenningsjessicaAug 21, 2025
  If you cannot change the temperature setting on your American Standard Temperature Controller, consider these possibilities: * You may have reached the upper or lower temperature limits. The heating limits are between 40 and 85°F, while the cooling limits are between 65 and 90°F. Check if your desired temperature falls within these ranges. * The keypad might be locked. If "Keypad locked" is displayed on the LCD, unlock it by pressing the Up and Down arrow buttons together until the lock icon disappears.
S
Stephen ThorntonAug 22, 2025
How to calibrate indoor temperature display on American Standard Temperature Controller?
- J
  Joshua FosterAug 22, 2025
  If the indoor temperature display on your American Standard Temperature Controller is incorrect, it might be that the temperature display needs calibration. Calibrate the sensor using User Setup Step 49.
S
Sheri HendersonAug 25, 2025
How to calibrate outdoor temperature display on American Standard Temperature Controller?
- J
  jodi48Aug 25, 2025
  If the outdoor temperature display on your American Standard Temperature Controller is incorrect: * The temperature display may need calibration. Try calibrating the sensor using User Setup Step 50. * Alternatively, disconnect the outdoor sensor from the controls terminal block and check the sensor and field wiring resistance value using Table 2.
P
Peter JohnsonAug 27, 2025
How to fix American Standard ACONT401AN21MA Temperature Controller when display will not come on?
- J
  Jason HollandAug 27, 2025
  If the display on your American Standard Temperature Controller won't turn on, there are several potential causes: * A blown fuse or tripped circuit breaker could be the issue. Replace the fuse or reset the breaker. * The furnace power switch might be off. Ensure the switch is turned to the ON position. * The furnace blower compartment door or panel may be loose or not properly installed. Replace the door panel correctly to engage the safety interlock or door switch.
B
Brett CervantesAug 28, 2025
What to do if heating will not come on American Standard Temperature Controller?
- R
  Robert SandersAug 28, 2025
  If the heating is not turning on with your American Standard Temperature Controller, here are a few things to check: * First, ensure the System Mode is set to Heat and that the setpoint is above the current room temperature. * There might be a minimum off time delay in effect. If the heating doesn't start within 5 minutes, proceed with further checks. * Inspect for loose connections to the control or the system and repair if necessary. * It's also possible that the heating system requires service or the control needs replacement.
J
James CarterAug 29, 2025
Why cooling will not come on American Standard ACONT401AN21MA Temperature Controller?
- J
  Jeremy Shaw Jr.Aug 30, 2025
  If the cooling isn't activating on your American Standard Temperature Controller, consider the following: * Ensure that the System Mode is set to Cool and the setpoint is below the room temperature. * A minimum off time delay might be active. If the cooling doesn't start after 15 minutes, further investigation is needed. * Check for any loose connections to either the control or the system and repair them. * The cooling system may require servicing, or the control unit might need to be replaced.
K
Kristin WangAug 31, 2025
How to stop American Standard Temperature Controller fan from running all the time?
- B
  Bradley BarnesAug 31, 2025
  If the fan on your American Standard Temperature Controller is constantly running, here are some potential solutions: * The fan mode might be set to ON. Change the fan mode to AUTO. * There could be a short in the control wiring. Check and repair the wiring as needed.
L
Lisa ThompsonSep 2, 2025
Why American Standard ACONT401AN21MA does not respond to keypad presses?
- W
  William ColemanSep 2, 2025
  If your American Standard Temperature Controller is not responding when you press the keypad, here are a couple of possible reasons: * The keypad might be locked. If the LCD displays "Keypad locked", unlock it by pressing the Up and Down arrow buttons together until the message disappears. * It is possible there is a keypad failure, which would mean replacing the control.
J
Jennifer JonesSep 3, 2025
What to do if American Standard ACONT401AN21MA outdoor temperature display shows dashes?
- P
  pamelabarnettSep 4, 2025
  If your American Standard Temperature Controller's outdoor temperature display shows "--" and the Service indicator is solid, the issue could be: * The outdoor temperature sensor is either open or shorted. * The outdoor sensor field wiring is open or shorted. To resolve this: 1. Replace the outdoor sensor. 2. Check and repair the outdoor sensor field wiring.
L
laurascottSep 5, 2025
Why American Standard Temperature Controller displays cool or heat on but no air?
- M
  Mark ThorntonSep 6, 2025
  If your American Standard Temperature Controller displays 'Cool ON' or 'Heat ON' but no air is coming from the registers, consider these possibilities: * The heating equipment may turn on the fan only after the furnace has warmed up to a specific temperature. Wait one minute after 'Heat ON' is displayed, then check the registers. * The heating or cooling equipment might not be operating correctly. Check the heating and cooling system.

American Standard ACONT401AN21MA Specifications

General

Brand	American Standard
Model	ACONT401AN21MA
Category	Temperature Controller
Language	English

Summary

Warranty

Limited Warranty

Extended warranty for the Comfort Control to original and succeeding owners in the US and Canada.

Introduction

Keypad Functions

MODE Key

Changes system mode to Heat, Emergency Heat, Cool, Automatic, or Off for HVAC operation.

UP/DOWN Arrow Keys

Used to raise or lower the Heat or Cool temperature settings on the control.

Fan Key

Selects indoor fan operation mode: automatic or continuous.

Filter/OD Key (Filter Reminder)

Manages filter replacement reminders by displaying remaining days and resetting the timer.

User Setup Options

Filter/OD Key Function

View outdoor temperature by pressing the FILTER/OD key when an outdoor sensor is installed.

Factory Default Settings

Features

Filter/OD Key (Filter Timer Setup)

Access quick setup for the filter timer (1-180 days) by pressing and holding the Filter/OD button.

Energy Savings Mode

Lowers energy consumption by adjusting setpoints for heating (cooler) and cooling (warmer).

Auto Changeover

Automatically switches between heating and cooling modes to maintain desired comfort levels.

Setpoint Deadband

Defines the separation between heating and cooling setpoints to prevent simultaneous operation.

Outdoor Temperature Display

Displays outdoor temperature when an optional sensor is installed via the Filter/OD keypad.

Backlit Display & Keys

Illuminates LCD and keypad for visibility; backlight stays on for 10 seconds after last key press.

Cooling Droop

Cycles compressor to improve comfort by removing moisture, controlling temp 1-2 degrees below setpoint.

Keypad Lock

Prevents tampering by locking keypad; press UP/DOWN arrows simultaneously to lock/unlock.

Troubleshooting

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American Standard ACONT401AN21MA User Manual

Table of Contents