Just when you think you can’t learn anything new about economizers, Honeywell is going to phase out all of those controls and is introducing a new control — the W7220. Not that the information on the old controls is obsolete — there are still a lot of those economizers out there. One of the nice things about the new control is it has a screen on it and actually does diagnostics (see attached information at the end of this post).
This new control does use a new set of sensors for mixed / discharge air as well as enthalpy. It can, however be used with the M7215 actuator currently being used.
C7250A1001/U 20k Temperature sensor for mixed or discharge air in roof top packaged equipment
The C7250 Mixed Air sensor is designed for use as a 20k input to a controller for mixed air temperature in rooftop packaged air conditioning equipment. A separate controller such as the JADE™ Economizer System (Model W7220) provides power and communications for the C7250 Mixed Air sensor.
Application: Electronic 20K temperature sensor for A 20K TEMPERATURE SENSOR INTENDED FOR SENSING MIXED OR DISCHARGE AIR IN ROOF TOP PACKAGED AIR CONDITIONING EQUIPMENT. USED WITH A W7220 ECONOMIZER CONTROLLER.
C7400S1000/U S-Bus Enthalpy Sensor – Outside, supply or return air
Digital enthalpy (humidity/temperature) sensor for use with S-Bus devices and W7220 economizer controller
- This unit mounted C7400S enthalpy sensor includes solid state temperature and humidity sensors.
- Outputs a digital communicating signal on a two-wire Sylkbus communications link, reporting the temperature and humidity separately to the controller.
- The controller determines the enthalpy (total heat), enabling economizer modes of operation when outside air enthalpy is suitable for free cooling.
- Enthalpy sensors are compatible with Honeywell economizer systems.
- When used with an economizer, the enthalpy boundary curve is programmed via the controller. When the temperature and humidity are determined to be suitable based on the relationship to the boundary, the controller allows outside air for economizing.
- Ambient temperature operating range from -40° to 150° F.
- Dual enthalpy sensors in outside air and return switches the controllers to economizer mode of operation anytime the outside enthalpy is less than the return air enthalpy.
Application: Provides Honeywell SYLK Bus signal in relation to enthalpy – 5% accuracy Sensor for A SOLID STATE ENTHALPY SENSOR DESIGNED TO SENSE TEMPERATURE AND HUMIDITY WITH 5% ACCURACY. USE WITH W7220 ECONOMIZER CONTROL, FOR USE IN OUTDOOR AIR INTAKES OF HVAC ROOFTOPS
As these new controls are introduced, I will be learning about them and then creating posts , as necessary about them. For now, be aware that this is occurring and your manufacturer my be supplying you with a KIT to replace existing economizer components with these new one..