Comfort Miser

An all-in-one electronic control system that can control the entire operation of a single or dual zone air handler with multiple stages of Air Condition, Booster Heat, Heat Reclaim, and Fan Blower.

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The Comfort-Miser HVAC Control System is an all electronic control system that can control the entire operation of a single or dual zone air handler with multiple stages of Air Conditioning, Booster Heat, Heat Reclaim, and Fan Blower, when available. The Comfort-Miser can control an air damper, auxiliary heater, and the anti-sweat heaters in refrigerated display cases. It can also monitor the outside air temperature and humidity.

The ComfortMiser HVAC Control System is available in two models:

  • ComfortMiser Single HVAC Zone Control System
  • The ComfortMiser Dual HVAC Zone Control System

The ComfortMiser HVAC Controller can control air handler systems with the following maximum configurations:

  • Fan Blowers -- Single and Two Stage Fan Blowers
  • AC Stages -- Up to 6 AC Stages--Staged either sequentially or round-robin.
  • Heat Reclaim -- Up to 4 HR Stages sequentially.
  • Booster Heat -- Up to 6 stages of Booster Heat (electric or gas fired).
  • Economizer Damper -- One two-position damper.
  • Auxiliary Heater -- One circuit.
  • Anti-Sweat Heater -- One circuit.
  • Alarm Relay -- One circuit.

For each air handler, a maximum of 16 relay outputs can be used in any condition.

Hardware -- The ComfortMiser operational programming is Flash EPROM or OTP EPROM stored. All logged data is stored within battery-backed memory with a minimum of a 5 year retention. Changes to setup and operating parameters can be made via a RS485/RS232 communications link or by the front panel keypad and display. The current run status of the HVAC zones is displayed on the front panel display and on a LED Status Panel. All connections for inputs, communications, power, and outputs utilize either deplugable Phoenix CombiCon wire terminals.

Temperature Control -- The primary function of the Comfort-Miser is to maintain the temperature in each of its assigned areas. The Comfort-Miser can control up to six AC stages, four Heat Reclaim stages, and six Booster Heat stages. The Comfort-Miser operates in a Cooling Mode and a Heating Mode and will automatically switch from one mode to another. Each stage will be activated based upon a 0.4 °F offset above the cooling setpoint or below the heating setpoint. Each stage can be set for a minimum run-time, and a user settable Cut In/Cut Out Span is available for each stage.

Heating Mode/Cooling Mode -- The ComfortMiser operates in two separate modes, Heating Mode and Cooling Mode. A Cooling Mode Setpoint and a Heating Mode Setpoint is programmed into the control. The temperature must exceed the setpoint of the non-active mode for over 30 minutes before the system will switch modes. For example, the ComfortMiser is operating in the Cooling Mode. The temperature drops below the Heating Mode setpoint. The temperature must remain below the Heating Mode setpoint for over 30 minutes before the ComfortMiser will switch to the Heating Mode and begin activating heat stages.

AC and Heat Staging -- Each stage has a common Cut in and Cut Out Temperature Setpoint and a Minimum Runtime Setpoint. ComfortMiser has an adjustable temperature deadband between the Cooling and Heating Modes and a 30 minute changeover time delay. Every stage is offset from each other by 0.4 °F.

De-Humidification -- The ComfortMiser utilizes Air Conditioning to remove moisture from the air. The ComfortMiser operates the De-humidification process in both the heating and cooling mode.

Setback Temperature Schedule and Differential Setpoint -- During certain regularly scheduled times, the controller can be programmed to run in the Setback Mode. When in the Setback Mode, the Cooling Mode Temperature Setpoint will be raised and the Heating Mode Temperature Setpoint will be lowered by the Setback Differential value. Three Setback Schedules can be programmed: Night Setback, Holiday Setback and an Extra Setback. Each schedule can be programmed for an On-time and an Off-time. The Holiday Setback schedule allows for 10 programmed holiday dates. The ComfortMiser gives the user the option of locking out Booster Heat while in Setback; this will delay the activation of the Booster Heat after the end of the Setback period.

Load Shedding -- During periods of peak energy demand, the ComfortMiser can be placed into a Load Shedding Mode. Each ComfortMiser zone has a digital input assigned as the control's Load Shedding Input. When this input reads a CLOSED signal from an energy management system, the control will enter the Load Shedding Mode. The control will raise the Cooling Mode Temperature Setpoint by the Load Shedding Differential value and will lower the Heating Mode Temperature Setpoint by the same differential value.

Economizer Air Damper -- (Available when the Outdoor Temperature and Humidity Sensor is enabled) In Cooling Mode, a two position air damper can be activated to open 100% when the outside air temperature is below 65 °F and the outside RH is less than 45%. The Economizer Air Damper can be forced into the open mode by energizing the Air Damper relay.

Booster Heat Lockout -- (Available when the Outdoor Temperature and Humidity Sensor is enabled) Each Booster Heat stage has a programmable lockout temperature setpoint. The Booster Heat will not be activated when the outdoor temperature is above this setpoint. Lockout can be forced into override by a user.

System Status Indication Panel -- Each ComfortMiser zone has a LED Status board on the front panel of the control housing. This panel will indicate the run status of each stage, the Fan status, Setback, Alarm status, and Dehumidification.

Auxiliary Heaters -- (Only when the Outdoor Temperature and Humidity Sensor is enabled) Auxiliary Heating is used to turn on/off a heating source according to the outside temperature, such as a vestibule air curtain or a sidewalk heater. The Auxiliary Heat Control has a programmable ON setpoint and a programmable ON Time of Day Schedule. The Auxiliary Heater will be activated when the outside temperature is below the ON Setpoint and the clock is within the range of the ON Time of Day Schedule. The schedule allows the Auxiliary Heater to be shut off during non-business hours.

Anti-Sweat Heater -- The ComfortMiser can activate the Anti-Sweat heaters mounted in the refrigerated display cases within their assigned HVAC zone. Anti-Sweat heaters are designed to prevent condensation from gathering on the glass doors and case frames by heating these surfaces to a temperature above the dew point. These heaters normally are large sources of electricity consumption. The heater circuits can be activated based upon a programmed schedule, an indoor humidity setpoint or both.