Quick Start Guide to Humidity Control on Sensi Classic and Sensi Touch
1. Contractor Firmware Update Process
If your Sensi thermostat has not yet received an over-the-air firmware update, follow these steps:
- Dial 1-888-605-7131.
- Press 2 for professional services, then press 3.
- Inform the agent you are at a customer's home and require a firmware update for hum/dehum capabilities. Provide the MAC ID from the back of the thermostat's faceplate.
2. Installation – Compatibility and Wiring
This section details the wiring connections for integrating humidification and dehumidification features with your Sensi thermostat.
Thermostat Wiring Terminals
| SENSI THERMOSTAT | CONVENTIONAL SYSTEM | HEAT PUMP SYSTEM |
|---|---|---|
| RH | Power for heating, 24V | |
| RC+ | Power for cooling, 24V | |
| C | Common wire, 24V | Common wire, 24V |
| Y | 1st stage cool | 1st outdoor stage heat |
| Y2/* | 2nd stage cool | 2nd outdoor stage heat and cool or humidifier |
| W/E | 1st indoor stage heat | 1st stage auxiliary/emergency heat |
| W2/* | 2nd indoor stage heat or dehumidifier | 2nd stage auxiliary/emergency heat or dehumidifier |
| G | Indoor blower (fan) | Indoor blower (fan) |
| O/B | Changeover (reversing valve) connection for heat pump or zone panel systems | |
| L | no function | "L" terminal connection |
Wiring Diagram Description: The diagram illustrates connections between the thermostat, a Furnace/Air Handler Terminal Strip, a System Transformer (providing 24V power), and a Humidifier (Water Solenoid Valve, 24V). Key connections include:
- The `Y2/*` terminal energizes on a call for humidification when there is also a call for heat.
- The `W2/*` terminal de-energizes on a call for dehumidification when there is a call for cool.
3. Configuration – Setting Humidification/Dehumidification Control Capability
This section outlines how to configure your Sensi thermostat to enable and manage humidity control features.
Configuration Menu Items Reference
| Display Code | Menu item | Default | Options |
|---|---|---|---|
| Wireless Setup | Connect | Connects Thermostat to Wi-Fi network | |
| Fahrenheit or Celsius | F | F, C | |
| Outdoor Equipment Configuration | AC1 | AC1- Conventional Cooling 1 (Single Stage), AC2- Conventional Cooling 2 (Two-Stage), HP1 - Heat Pump 1 (Single Stage), HP2- Heat Pump 2 (Two-Stage), ACO- No Cooling | |
| Indoor Equipment Configuration For Gas or Electric Heat | EL2 | EL1- Electric 1 (Single Stage), EL2- Electric 2 (Two-Stage), Fan, GA1 Gas 1 (Single Stage), GA2 Gas 2 (Two-Stage) | |
| Fn | Reversing Valve Position O/B/6/None | 0 | O, B, 6, None |
| H AA | Humidification For Heat Pumps Only | OFF | OFF, ON (5% increments) |
| H SP | Humidification Set Point | OFF | OFF/5% - 50% (5% increments) |
| dH AA | Dehumidification Add Accessory | Od | Od - Optimal dehumidification (Overcool to dehumidify), Oc - Optimal comfort (Wired dehumidification), Off/40% - 95% (5% increments) |
| dH SP | Dehumidification Set Point | OFF | OFF/On |
| Wireless Radio | ON | Turns Wi-Fi Radio On/Off |
Thermostat Interface: The thermostat allows configuration through menus like 'Advanced Set Up' and 'Set Up HVAC Equipment'. Users can select equipment types, reversing valve positions, and enable/set points for humidification and dehumidification. The interface displays current settings and allows adjustments using navigation buttons (e.g., 'Menu', 'Mode', 'Fan', 'Schedule').
Sensi App Interface: The Sensi mobile application provides a 'System Settings' menu where users can adjust 'Circulating Fan' percentage, 'Humidification' setpoint (e.g., 40%), 'Dehumidification' setpoint (e.g., 60%) and mode (Optimal Comfort), and 'A/C Protection' settings.
4. Using the Feature – Turning Humidification Control On/Off and Setting the Humidity Setpoint
This section details how to manage humidity control directly from the thermostat or via the Sensi App.
Humidification Control
At the Thermostat: Navigate to 'Advanced Set Up' then 'Humidify'. You can turn the feature ON/OFF and set a desired humidity level (e.g., 'Set To 50%'). This uses your wired humidifier to add moisture.
In the Sensi App: Access 'System Settings' to adjust the 'Humidification' slider to your preferred percentage (e.g., 40%).
Dehumidification Control
At the Thermostat (Wired Equipment): Navigate to 'Advanced Set Up' then 'Dehumidify'. Turn ON/OFF and set the desired humidity level (e.g., 'Set To 50%'). This uses your wired dehumidifier or slows the system's fan speed to remove moisture.
At the Thermostat (Overcooling): For systems without a dedicated dehumidifier, Sensi can enable 'Dehumidification using overcooling'. This feature allows the system to overcool up to 3º below your set point to remove excess moisture. The interface shows ON/OFF and a setpoint (e.g., 'Set To 50%').
In the Sensi App: Access 'System Settings' to adjust the 'Dehumidification' slider to your preferred percentage (e.g., 60%) and select a 'Mode' (Optimal Comfort or Optimal Dehumidification).
Frequently Asked Questions
| FAQ | Answer |
|---|---|
| When can I get the firmware OTA update for the humidity control? | Firmware updates for humidity control are automatically installed once a Sensi smart thermostat is connected to the internet. |
| Which versions of Sensi thermostats are compatible with Humidity control? | Sensi Touch (1F95U) and Sensi Classic (1F87U) thermostats are all backwards compatible. 1F86U and UP500W models are currently not compatible. |
| What terminals should I use to enable the humidity control? | Use Y2/* for humidification and W2/* for dehumidification. |
| What types of humidifiers and dehumidifiers are supported? | Humidifiers: Any 24VAC humidifier. Sensi does not support independent humidification (from a call for heat). Dehumidifiers: HVAC systems with a dehumidify mode (slowing of the system's fan speed) or 24VAC dehumidifiers. Sensi does not support independent dehumidification (from a call for cool). |
| What is an appropriate humidity setpoint? | Depending on the outdoor temperature, the ideal indoor humidity level is between 30-50% RH. In cold weather, if condensation appears on your windows, lower the humidity setpoint. |
| What is Overcooling to Dehumidify? | On air conditioning systems without a dehumidifier, the dehumidification feature allows Sensi to overcool to a maximum of 3º below the AC setpoint to help control humidity. Systems with dehum terminals on the air handler or wired dehumidifiers will use those capabilities rather than overcooling. |
| Why is my system unable to reach my humidity setpoint? | During extremely cold and dry or hot and humid climates, your humidifier or dehumidifier may not be able to increase or decrease humidity enough to reach your setpoint depending on the size of your equipment. |
