Bard CH3S1 Sequence Of Operation, High Pressure Switch And Lockout Sequence, Manual, Page, 5 of

DRAIN: Connect a drain trap to the drain fitting under the bottom of the dehumidifier section of the unit. The drain connection is a ¾" female pipe fitting. The use of a trap is required to ensure proper drainage.

AIR CHANNEL ASSEMBLY: (See Figure 3.) Remove cover plate in unit and cut out the insulation. On CH3S1 models, the duct extension is to be removed and a new piece of foam (supplied) added to the bottom of the air channel assembly. Slide the air channel assembly into the unit and position the assembly to the left until the angle hits the side of the inner back. Secure the angle with three self-drilling screws. Secure the top with one screw.

SEQUENCE OF OPERATION

Dehumidification – Circuit DH makes at the humidistat pulling in the compressor contactor, starting the compressor and the dehumidifier blower motor. The “G” (indoor motor) is automatically completed on call for dehumidification (Relay #2).

The dehumidifier may operate alone or run simultaneously with the first stage of the CH unit. When the CH unit switches to second stage, the operation of the dehumidifier will be locked out (Relay #1).

The Compressor Control Module is an anti-short cycle/ lockout timer with high and low pressure switch monitoring.

On initial power up or any time power is interrupted to the unit, the delay on make period begins, which will be two minutes. When the delay on make is complete and the high pressure and low pressure are closed, the compressor contactor is energized. Upon shutdown, the delay or break timer starts and prevents restart until the delay on break and delay on make have expired.

During routine operation of the unit with no power interruption, the compressor will operate on demand with no delay.

HIGH PRESSURE SWITCH AND LOCKOUT SEQUENCE

If the high pressure switch opens, the compressor contactor will de-energize immediately. The lockout timer will go into a soft lockout and stay in soft lockout until the high pressure switch closes and the delay on break time has expired. If the high pressure switch opens again in the same operating cycle, the unit will go into manual lockout. Recycling the wall humidistat resets the manual lockout.

LOW PRESSURE SWITCH BYPASS & LOCKOUT SEQUENCE

If the low pressure switch opens for more than 120 seconds, the compressor contactor will de-energize and go into a soft lockout. Regardless the state of the low pressure switch, the contactor will re-energize after the delay on make time delay has expired. If the low pressure switch remains open longer than 120 seconds, the unit will go into manual lockout. Recycling the wall humidistat resets the manual lockout.

NOTE: Both high and low pressure switch controls are inherently automatic reset devices. The high pressure and the low pressure switch cut out and cut in settings are fixed. The lockout features, both soft and manual, are a function of the compressor control module.

FREEZE STAT OPERATION: The freeze stat operation will open at 32° and de-energize the compressor and fan. The compressor and fan will restart after the coil defrosts and the freeze stat warms to 57°.

PRESSURE SERVICE PORTS

High and low pressure service ports are installed on the unit, so the system operating pressures can be observed. To gain access to these pressure ports, remove the long narrow panel on the right-hand side of the outdoor section of the CH unit. See Figure 4.

Reference the pressure table located on the front lower panel and Table 2 within this manual.

Manual	2100-506D
Page	5 of 14