Toshiba TRANQUILITY 20, TRANQUILITY 27 manual Flushing/Purging Units with ClimaDry

Flushing/Purging Units with ClimaDry

Units equipped with ClimaDry must be flushed/purged with a flush cart. Detailed general flushing /purging instruction can be found in the Flow Controller III IOM.

The unit must be powered (but not operating) during flushing/purging. Unit power is required to operate the three-way modulating valve during flushing.

When flushing/purging units equipped with ClimaDry the earth loop should be fully flushed/purged before attempting to flush/purge the heat pump. Once the earth loop is flushed, position the flushing valves to flush the heat pump. Then with flushing flow re-directed through the unit, energize the modulating three-way dehumidification valve to allow flow through the dehumidification hydronic circuit.

Energize the modulating three-way dehumidification valve by removing the red wire from the ACC1 ‘N.O.’ terminal on the DXM board. Connect this wire to the ACC1 ‘NC’ terminal of the DXM controller, as shown in figure 1, to energize the modulating three-way dehumidification valve. Once energized, the valve will take 45 – 75 seconds to fully shift. Continue flushing during this time. After the valve has completed its shift, use the air bleed from the top of the reheat coil to purge air from the coil.

Note, if the ClimaDry sensor, located in the supply air stream is above 70°F it must be disabled to allow the modulating valve to shift. Disable this sensor by removing the white wire from the Low Voltage Terminal Block (LVTB) shown in figure 1.

Figure 1. Flushing/Purging Wiring

White Thermistor Wire Red Three-Way Valve Wire

De-energize the valve by removing the red wire from the ACC1 ‘NC’ terminal on the DXM board. The valve will spring return to its normal position in just a few seconds. After the valve has fully returned, repeat the process of running the valve through its cycle and purging air from the reheat coil.

Under extreme circumstances this procedure may be required multiple times to purge all air from the circuit. After completing the flushing/purging procedure, restore the red wire to the ACC1 ‘N.O.’ terminal on the DXM for normal operation. Return the white sensor wire to the LVTB, if it was removed, as shown in figure 2.

White Thermistor Wire Red Three-Way Valve Wire

Figure 2. Normal Unit Wiring

Extra care must be taken when using non-pressurized flow centers to ensure all air is removed from the unit and no additional air is allowed into the system. If air is allowed to collect in the ClimaDry piping, nuisance trips may occur. Additional flush/purge cycles may be used when required.

ClimaDry Whole House Dehumidification - ClimateMaster Geothermal Heat Pumps - Rev.: 18 April, 2008B

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