Indoor Air Quality Control and Monitoring

• Indoor Air Quality Control and Monitoring
  • Humidification
  • Dehumidification (Residential)
  • Dehumidification Away Mode
  • Ventilation
  • Indoor Air Quality Monitoring (S1100 and S1200 only)

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Humidification

The thermostat reads the indoor humidity level and allows the user to set a humidification setting with or without window protection. The humidifier settings are shown in the ISU chart from ISU 8000 to ISU 8100.

Set up Humidification

1. Select the Humidifier Type at ISU 8000. Based on the humidifier type you select, the thermostat defaults to the most commonly used settings for that humidifier type. For example, a Bypass or Fan Powered humidifier will default ISU 8070 to “Humidify Only when Heat is On”.
   A Steam humidifier will default ISU 8070 to “Humidify on Demand; Thermostat Controls Fan".

2. Set Window Protection setting (ISU 8050).
   Outdoor sensor temperature (Sensor or Internet weather) is required for Window Protection (ISU 1060).

3. Select the system mode(s) to allow humidification (ISU 8060). Options are Heat and off. Heat includes Heat, Emergency Heat and Auto. If the system is in Auto mode, the thermostat will allow humidification if the last call was for heat. If a discharge air sensor is used, there will also be an option to humidify in cool mode. The discharge sensor monitors the air temperature to ensure that the air in the duct is warm enough to not cause condensation when humidifying. Humidifying in cool mode might be desired in certain hot dry climates.

4. Select from one of the Humidification Control Options (ISU 8070).

   • Hum when Heat is On

     • The thermostat turns on the humidifier only if the heat is currently running and humidification is needed.

   • Hum when Fan is On

     • The thermostat turns on the humidifier only if the fan is currently running and humidification is needed.

   • Tstat Controls Fan

     • The thermostat turns on the humidifier and the fan when humidification is needed.

   • Hum Controls Fan

     • The thermostat turns on the humidifier when humidification is needed and the humidifier controls the fan.

Control Humidification Level (If thermostat has been wired and setup to control a humidifier)

1. Touch MENU and select Humidification.
   Use the slider bar to select the desired humidity level. Typically this will be a setting between 35 to 55% RH.

2. Touch Save to save your settings.

3. If frost or condensation appears on the windows due to too much humidity, enable Window Protection and adjust the level.

Window Protection

Window Protection limits the amount of humidity to prevent frost or condensation on windows. To use Window protection, the ElitePRO™ Series Thermostat must know outdoor temperature from an outdoor sensor or the First Alert App.

The thermostat prevents frost or condensation on windows by not allowing the humidifier to run above a certain level. To prevent frost or condensation, the thermostat may turn off the humidifier before the humidity setting is reached.

You can adjust the Window Protection setting by touching MENU, then select Humidification > Options > Window Protection Level. Window Protection is set on a scale from 1-10. A setting of 10 represents poorly insulated windows and a setting of 1 represents well insulated windows. A higher number automatically reduces the humidity to help prevent frost or condensation on your windows. Use a lower number if indoor air seems too dry. To prevent frost/condensation on your windows during cold outdoor temperatures, poorly insulated windows require a higher Window Protection setting, which will limit how much your humidifier can run. After you set the Window Protection setting, check for frost/condensation on your windows in the morning. If frost/condensation is present, adjust the Window Protection setting to the next higher number and check for frost/condensation on your windows the next morning.

Continue to adjust the Window Protection setting to a higher number until frost/condensation is no longer present. If Window Protection is turned Off, the thermostat controls the humidity level to the user's desired humidity setting. Frost or condensation may appear on windows.

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Dehumidification (Residential)

The thermostat reads the indoor humidity level and allows the user to set a dehumidification setting. The thermostat controls the humidity level using the cooling system or a whole house dehumidifier.

Dehumidification Using the Cooling System

When set for A/C with Low Speed Fan, A/C with High Speed Fan or Reheat, an over-cooling limit can be set from 0 °F to 3 °F (ISU 9070). The thermostat uses the cooling system to reduce humidity by lowering the temperature as much as 3 °F below the current cool set point until the desired humidity level is reached.

If set for A/C with Low Speed Fan, configure the U or L contacts as Normally Open or Normally Closed (ISU 9050) and wire to the Low Speed Fan terminal on the equipment. For example, if the U or L contacts are normally closed, they will open when the thermostat calls for dehumidification.

If humidification and dehumidification are both set up to operate in the system mode (Off), the thermostat will automatically enforce a 15% deadband between the humidification and dehumidification settings. The thermostat will automatically switch between humidification and dehumidification to maintain the desired humidity level.

Dehumidification Overcooling Limit (ISU 9070):

This option uses the cooling system to lower the temperature up to 3° F below the current cool set point until the desired humidity is reached. The Dehum Over-Cooling Limit range is from 0° to 3° F if set for low-speed fan and 1° to 3° F if set for high-speed fan.

Set up Dehumidification With Cooling System

Some screens shown in this section may not appear on the thermostat, depending on how you set up dehumidification.

1. Select the Dehumidification Equipment in ISU 9000.

2. Select which terminals the dehumidifier equipment is wired to in ISU 9040.

3. Select whether the U or L terminals are Normally Open or Normally Closed (ISU 9050).

   • Normally Open – contacts are normally open and will close during a call for dehumidification

   • Normally Closed – contacts are normally closed and will open during a call for dehumidification.

4. Set the Over-cooling Limit (ISU 9070).
   Options:

   • 0 °F to 3 °F (A/C with Low Speed Fan)

   • 1 °F to 3 °F (A/C with High Speed Fan)

Dehumidification Fan Speed Priority (See ISU 9005)

If the house has circulation issues to certain parts of the house when running in low speed, this feature will allow the thermostat to use the high speed fan more often so that the conditioned air has better circulation within the home.

• Low Speed Fan with Cool Stage 1 Only when the thermostat is set to humidify with low speed fan, and humidity is high, and cooling is running at stage 1, always run with the low speed fan. When cooling goes to stage 2, it ramps up to high speed fan.

• Low Speed Fan Always Regardless of which cooling stage is active, the thermostat will exclusively use the low speed fan when dehumidifying.

• User Selectable The homeowner can set the high speed fan priority based on their comfort level (reachable via Menu > Dehumidification > Options > High speed fan)
  If set to 10, the thermostat will always use the high speed fan and never switch into low speed mode operation. If set to 0, the thermostat will only use the low speed fan and never switch to the high speed fan when the humidity level is above the Dehumidification setting.

  

Dehumidification Using a Whole House Dehumidifier

The Whole House Dehumidifier option requires a dedicated unit for dehumidification. The thermostat can be set to control dehumidification in all modes (Heat, Off, Cool [ISU 9120]). Set up Dehumidification With Whole House Dehumidifier (Some screens shown in this section may not appear on the thermostat, depending on how you set up dehumidification.)

1. Select the Dehumidification Equipment in ISU 9000.

2. Select the system mode(s) to allow dehumidification ISU 9120.

   Heat includes Heat, Emergency Heat and Auto. If the system is in Auto mode, the thermostat will allow dehumidification if the last call was for heat. Cool includes Cool and Auto. If the system is in Auto mode, the thermostat will allow dehumidification if the last call was for cool.

3. Set Dehumidifier Fan Control settings ISU 9130.

   • Tstat Controls Fan Thermostat turns on the dehumidifier and the fan when dehumidification is needed.

   • Equip Controls Fan Thermostat turns on the dehumidifier when dehumidification is needed. The fan is controlled by the equipment.

4. Set the desired lockout option.

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Dehumidification Away Mode

See ISU settings 9180-9200.

If configured for dehumidification away mode by the installing pro, your system can be set to control indoor climate while your home is vacant during the humid season. Before you leave, touch MENU, then select Dehumidification Away Mode. Temperature and humidity will be kept at levels that protect your home and possessions. When you return, touch Stop to resume normal operation.

Set up Dehumidification Away Mode

1. Select Allowed at ISU 9180.

2. Set Fan Control settings at ISU 9190.

• On: Fan is always on.

• Automatic: Fan runs only when cooling system is on.

• Circulate: Fan runs randomly, about 35% of the Time.

3. Set temperature and dehumidification settings at ISU 9200

• Low Limit Temperature Setting If the cooling system is used to control humidity while Dehumidification Away Mode is active, the thermostat allows the cooling system to lower the indoor air to the Low Limit Temperature Setting to reach the Dehumidification Setting.

• Temperature Setting
  The temperature maintained while Dehumidification Away Mode is active and the desired humidity level is satisfied.

• Dehumidification Setting
  The desired humidity level while Dehumidification Away Mode is active.

Control Dehumidification Level (If thermostat has been setup to control a dehumidifier or AC with High Speed fan)

1. Touch MENU and select Dehumidification.

2. Use the slider to adjust the desired Dehumidification level. Typically this will be a setting below 65% RH.

3. Touch options if you want to enable/disable the dehumidifier.



When disabled, the display will show off when viewing the dehumidifier setting screen.

4. Touch Save to save your settings.

AC with High Speed Fan

If the thermostat was set to “AC with High Speed Fan” in setup #9000, the thermostat will run the cooling below the cool setting when humidity is high. The maximum over-cooling is 3 degrees, but it may over-cool to a lesser degree depending on how far above the dehumidity setting the RH level in the home is.

Dehumidification: Commercial

The thermostat reads the indoor humidity level and allows the user to set a dehumidification setting. The thermostat controls the humidity level using the cooling system or a dehumidifier.

If humidification and dehumidification are set up to operate in the same system mode (Heat, Cool, Off) and you are sensing humidity from one location, the thermostat will automatically enforce a 15% deadband between the humidification and dehumidification settings. The thermostat will automatically switch between humidification and dehumidification to maintain the desired humidity level.

If humidification and dehumidification are set up to operate in the same system mode (Heat, Cool, Off) and you are sensing humidity from two different locations using a remote wireless indoor sensor (for example, main level and crawl space), the thermostat will allow humidification and dehumidification to operate at the same time, and there is no deadband between humidification and dehumidification settings.

Dehumidification Equipment Options: (ISU 9000)

• A/C with Low Speed Fan

• A/C with High Speed Fan

• Hot Gas Bypass

• Dehumidifier

Basic: This option uses the cooling system to reach the desired humidity level. Minimum On Time, High Humidity Comfort Reset and Reheat are not used with this method. This setting is commonly used if your dehumidification equipment is Hot Gas Bypass.

Minimum On Time (ISU 9090): This option ensures that the compressor runs long enough to effectively reduce humidity when the cooling equipment is cycled on. The compressor will run for the minimum “on time” you set until the desired humidity level is reached.

High Humidity Comfort Reset (ISU 9100): This option uses the cooling system to lower the temperature up to 5° F below the current cool set-point until the desired humidity is reached. The high humidity comfort range is from 1° to 5° F.

High Humidity Comfort Reset with Minimum On Time (ISU 9090 and 9100): This method uses both options above to reduce humidity while maintaining a comfortable temperature.

Reheat (ISU 9080): This option allows heating to run during dehumidification to help maintain a comfortable temperature. If only cooling stage 1 is used, during the “off” cycle, both cooling and heating run at the same time as needed to dehumidify without over-cooling. This option cannot be used in the Heat mode. This option is effective only if using a system with the A-Coil located before the heating coil (heat exchanger). This feature requires a conventional forced air heating system (gas, oil, or electric) in the application.

Reheat with Minimum On Time (ISU 9080 and 9090): This method uses both Reheat and Minimum On Time options above to reach the desired humidity level.

If set for A/C with Low Speed Fan, configure the assigned set of U contacts as Normally Open or Normally Closed (ISU 9050) and wire to the Low Speed Fan terminal on the equipment. For example, if the U terminals are normally closed, it will open when the thermostat calls for dehumidification. See Indoor Air Quality Control and Monitoring.

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Ventilation

The thermostat can be set for the following ventilation types: (ISU 10000)

• ERV/HRV

• Passive (Fan Only)

• Fresh Air Damper

• Economizer (The Economizer settings are in a different section and used only when the ElitePRO™ Series Thermostat is set for commercial application)

Ventilation Control Methods (ISU 10050)

Ventilation can be setup to meet either ASHRAE or Percent On Time settings. To meet these settings, the thermostat will ventilate during calls for Heat, Cool and Fan. If the required ventilation has not been achieved for ASHRAE or Percent On Time, the thermostat will force the ventilation equipment on.

ASHRAE

The thermostat operates ventilation equipment to meet the ASHRAE 62.2 ventilation standard based on CFM, number of bedrooms, and square footage of the house.
ASHRAE 62.2 can only be met if the ventilation equipment is running. If the ventilation equipment is off for any reason (outdoor ventilation lockouts, set up to turn Off during Sleep period, turned off by user, etc.), ASHRAE 62.2 is not met during those times. See ISU 10125 to select a Ventilation Priority.

Percent On Time

The thermostat operates ventilation equipment based on a percentage entered in the installer setup (ISU 10120). For example if Percent On Time is set to 50%, the ventilation equipment will run at random times during a 1 hour period until it reaches a 50% run time (approximately 30 minutes). Default setting is 30%. Range is 10% to 100% in 10% increments.

Ventilation Fan Control (ISU 10060)

• Tstat Controls Fan

  • The thermostat turns on the ventilator and the fan when ventilation is needed.

• Equip Controls Fan

  • The thermostat turns on the ventilator when ventilation is needed. The fan is controlled by the equipment.

Ventilation Priority (ISU 10125) Lockouts are Priority

The thermostat places a priority on lockouts versus the ASHRAE 62.2 ventilation standard. The thermostat will not run ventilation during the following lockout conditions (if configured) unless you manually call for ventilation:

• Lockout Ventilation during Outdoor Conditions (ISU 10130)

• Lockout Ventilation during “Sleep” program periods.

  This option is set by the user on the Ventilation screen. From Home touch Menu > Ventilation > Options > Disable During Sleep.

• Turn on ventilation due to a custom Dry Contact Alert setting. This is if someone set ISU 6005 for a custom Dry Contact Alert and set ISU 10065 to turn on the ventilator.

• Lockout ventilation due to a custom Dry Contact Alert setting. This is if someone set ISU 6005 for a custom Dry Contact Alert and set ISU 10145 to lock out the ventilator.

Opposite actions cannot be selected for the same custom dry contact (Ex. user cannot select both to Turn Ventilation On and Lockout Ventilation for the Custom Dry Contact 1).

If opposite actions are triggered at the same time due to different custom dry contacts (example, Dry Contact Alert 1 set to turn on ventilator and custom dry contact 2 set to lock out ventilator), Lockout Ventilation has priority over Turn Ventilation On.

ASHRAE is Priority

ASHRAE requires additional ventilation following a long off cycle. The thermostat meets the ASHRAE 62.2 ventilation standard by running additional ventilation when outdoor conditions are favorable. If ASHRAE cannot be met when outdoor conditions are favorable, the thermostat will override the outdoor lockouts and run ventilation. When using this option, it is recommended to increase the rate (CFM) of the ventilation equipment to meet the ASHRAE 62.2 ventilation standard in a shorter run time.

Ventilation — Outdoor Condition Lockouts (ISU 10130)

Ventilation will not operate when outdoor conditions exceed the lockout settings unless you manually call for ventilation or Ventilation Priority (ISU 10125) is set to ASHRAE is Priority and ventilation is needed to meet ASHRAE. Lockouts can prevent ventilation during extreme weather conditions to keep humid, hot, and cold air out of the home.

Options are:

• Ventilation Low Temperature Lockout Set-point (Off, -20° to 40° F)

• Ventilation High Temperature Lockout Set-point (Off, 80° to 110° F)

• Ventilation High Dew point Lockout Set-point (Off, 65° to 85° F)

Refer to the information below if you need assistance setting the High Dew point Lockout.

• Higher than 80: Extremely uncomfortable

• 75 to 80: Very uncomfortable

• 70 to 74: Quite uncomfortable

• 65 to 69: Somewhat uncomfortable

• Ventilate On High Indoor Humidity (ISU 10160)

If set to ventilate on high indoor humidity, the ventilator turns on to remove excess humidity if the indoor humidity is 10% above the humidification setting. The thermostat must be in the Heat mode to ventilate on high indoor humidity. If frost control is used, then the ventilation setting will adjust to stay approx. 10% RH above the humidity setting.

• Ventilate on high CO2 (ISU 10200). If selected, the ventilator will run when estimated CO2 levels exceed 1200 PPM. Once the ventilator has turned out based on CO2 levels it will continue to ventilate until estimated CO2 level drops to approximately 1100 PPM (unless additional ventilation is required based on either the Ashrae or % on time settings).

Control Ventilation Level

1. Touch MENU, and select Ventilation. You can check or change the ventilation mode.
   Mode:

• Auto: Ventilation runs to follow either Ashrae requirements or % on time requirements programmed by the installer.

• Off: Ventilation remains off unless turned on using the timer.

• Timer: To temporarily turn the ventilator on, use the up arrow to set the number of minutes you want the ventilator to run (0-180 minutes). To cancel a temporary setting, touch “Cancel Timed Ventilation”.

2. Touch Save to save your settings.

The display will show whether the ventilator is currently running under “Equipment status”.

Lockout During Sleep:

Under the ventilation menu, touch Options”. Select or deselect Disable During Sleep. Touch the back arrow in upper left of display to return to previous screen.

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Indoor Air Quality Monitoring (S1100 and S1200 only)

The S1100 and S1200 ElitePRO Thermostat monitors for Carbon Dioxide (CO2), Volatile Organic Compounds (VOCs), and Humidity. A general air quality level is shown under the temperature reading from the home screen. More detailed readings are shown when Air Quality is selected from the menu. Air Quality is rated as Great, Good, Fair, Poor and Very Poor. A Poor or Very Poor reading doesn't necessarily mean that the air quality presents a hazard. The S1100 and S1200 ElitePRO Thermostat is not a substitute for a dedicated CO2 or VOC sensor and only measures the room in which the thermostat is installed. Alerts at the S1100 and S1200 ElitePRO Thermostat thermostat are for awareness only.

Carbon Dioxide (CO2)

Carbon dioxide is produced by breathing and from any gas (combustion) appliance such as a gas furnace, gas stove top and/or oven, etc.

Volatile Organic Compounds (VOCs)

VOCs are chemicals that can come from common household items like paint, cleaners, and furniture. While it's normal to have some VOCs present in the air, it's good to keep spaces ventilated.

Solutions for poor Indoor Air Quality:

Carbon Dioxide (CO2):

Carbon dioxide is produced by breathing and from any gas (combustion) appliance such as a gas furnace, gas stove top and/or oven, etc. If CO2 is high, it is most likely indicating insufficient ventilation for the number of people in the space. Running the exhaust fan while cooking or opening windows can help in some cases, however if outdoor air quality is poor due to conditions such as forest fires, outdoor barbeques, burning leaves, a window over the vent of a running dryer, etc. then opening a window may be the cause of the poor air quality indoors. If the indoor CO2 is regularly high, Honeywell Home offers whole home ventilation solutions. In most cases proper ventilator will greatly reduce the CO2 levels in a home. These products are sold and installed by HVAC pros. The ElitePRO™ Series Thermostat can control a whole home ventilator.

Volatile Organic Compounds (VOCs):

VOCs are chemicals that can come from common household items like paint, cleaners, and furniture. While it's normal to have some VOCs present in the air, it's good to keep spaces ventilated. Running the exhaust fan while cooking and opening a window when outdoor air quality is good will help improve air quality. Honeywell Home offers whole home ventilation solutions. In most cases proper ventilator will greatly reduce the VOC levels in a home. These products are sold and installed by HVAC pros. The ElitePRO™ Series ThermostatElitePRO™ Series Thermostat can control a whole home ventilator.

Humidity:

The ElitePRO™ Series ThermostatElitePRO™ Series Thermostat detects the humidity level at the thermostat and/or wireless indoor sensors. The ElitePRO™ Series ThermostatElitePRO™ Series Thermostat can control a humidifier or dehumidifier to maintain more comfortable levels of indoor humidity. These products are sold and installed by HVAC pros.

Disabling Air Quality Monitoring on Thermostat:

At the time of the initial thermostat release, the Air quality monitoring cannot be disabled, however there will be an over-the-air update shortly after launch which will allow for this to be turned off if air quality monitoring is not desired. At that time, the firmware on new thermostats will also have this update.

Disable push notifications and email notifications:

The homeowner can disable push notifications and email notifications through the First Alert app. In the app, select the thermostat. Select the Gear icon in lower right. Select Alert management. Scroll down to the Carbon Dioxide and VOC alert options. Adjust those settings as desired.