Description
Electronic wall mount thermostat (typically mounted outdoors) c/w output status leds designed to fulfil the need for an independent economy cycle control system when a A/C units propriety thermostat cant also control an add on economy cycle set of dampers. Although not an ideal method of independently controlling the A/C’s units compressors with one control device with its own setpoint, and another control device like this ECCO thermostat independently controlling just the economy cycle also with its own setpoint , but quite often there simply isn’t another economical solution.
The ECCO-Y-24v is primarily intended for on/off limit temperature control based on low & high temperature limits operating a common relay to disable an external 0-10v temperature control signal typically being used to modulate a set of economy cycle damper motors. This thermostat is intended to work in conjunction with a R/A duct sensor / controller as per Hevac DSC2 (or room temperature sensor/controller RSC2) that produces a proportional 0-10v cooling control signal that can be used to modulate an economy cycle damper set based on return air temperature ie above 23c..
The external o-10vDC temperature control signal passing through this thermostat can be set with an overriding minimum position signal which is normally required with a economy cycle control system to maintain a minimum amount of fresh air regardless of outside conditions. The Low limit & High limit operation can also be individually disabled .
The ECCO can also pass through an external 0-10vDC CO2 air quality control signal to high select with the temperature control signal to control the economy set of dampers.
The status of the 2 external 0-10v signals (typically return air temperature & CO2) are indicated by variable intensity leds to give a quick visual indication of their respective outputs.
The ECCO can also be interlocked with any external switching device with voltage free contacts to force on the internal inhibit relay to inhibit use of the economy cycle system. For this purpose Hevac stock a small strap on fixed thermostat model HMT intended to be cable tied to the A/C’s units evaporator coil & interlocked with the ECCO’s D3 & M terminals to disable economy cycle operation if the unit is actually running in R/C heat mode (coil face temperature over 30c) as could be the case with the A/C operating under its own control system.
