Do you have a question about the Bard WH421 and is the answer not in the manual?
Information on National Electrical Code standards relevant to installations.
Standards for installation of air conditioning and ventilating systems.
Standards for warm air heating and air conditioning systems.
Methods for load calculation in residential air conditioning.
Guidance on designing low-pressure duct systems.
Contact details for organizations providing HVAC standards.
Explains the coding system for wall-mount heat pump models.
Procedures and considerations for mounting the unit to the wall.
Specific steps for securing the unit using brackets and fasteners.
Common installation scenarios and configurations for wall-mount units.
Guidance on sizing and connecting the main power supply to the unit.
Instructions for low voltage connections, including thermostat wiring.
Specifics on thermostat wiring, compressor cutoff, and heat anticipation.
Explains the function of indicator lamps on the thermostat.
Describes how to manually set the system to emergency heat.
Explains the compressor malfunction indicator and its causes.
Advice for improving start-up performance of the unit.
Information on crankcase heaters and their importance for compressor protection.
Details on the remote reset high pressure switch and its function.
Specific start-up procedures for three-phase scroll compressors.
Explains the function of the phase monitor for three-phase units.
Provides general advice for servicing the unit and maintaining performance.
Describes how the unit operates in cooling and heating modes.
Information on locating and using pressure service ports for system checks.
Explains the operation and control of the defrost cycle in heat pump mode.
Step-by-step procedure for troubleshooting the heat pump control.
Instructions for checking the outdoor unit temperature sensor's resistance.
Specifies correct fan blade settings for optimal air delivery.
Provides step-by-step instructions for fan shroud removal and reinstallation.
Details correct system R-22 charge and suction line temperatures.
Data on maximum external static pressure for unit operation.
Tables showing cooling pressures at various temperatures and conditions.
Tables showing heating pressures at various temperatures and conditions.
Lists available optional accessories for the unit.