Bard QC501 Start Up, Optional Cfm, Important Installer Note, Service Hints, Sequence Of Operation

START UP

OPTIONAL CFM

These units are shipped from the factory set to operate at the optional CFM level shown in Table 4. This provides lower operating sound levels for non-ducted, free discharge applications. This CFM level will reduce the system capacity performance by approximately 2% at the same energy efficiency.

Rated CFM is required for ducted applications for maximum performance rating. To obtain full CFM on these models, connect jumper wire as follows:

1.Disconnect all power to the unit. Failure to do so may result in damage to the motor.

2.Open hinged return air grille panel

3.Open control panel cover.

4.Add pink jumper wire (provided) to terminal 5 and 6 on the terminal board.

5.Reverse steps to reassemble.

IMPORTANT INSTALLER NOTE

For improved start up performance, wash the indoor coil with dishwashing detergent.

SERVICE HINTS

1.Caution user to maintain clean air filters at all times. Also, not to needlessly close off supply air registers. This may reduce air flow through the system which shortens equipment service life as well as increasing operating costs and noise levels.

2.The wall thermostat perform multiple functions. Be sure that all function switches are correctly set for the desired operating mode before trying to diagnose any reported service problems.

SEQUENCE OF OPERATION

FIRST STAGE COOLING – Circuit R-Y makes the thermostat open the first stage cooling water valve.

SECOND STAGE COOLING – Circuit R-Y2 make the thermostat open the second stage cooling water valve. The G (indoor motor) circuit is automatically completed on any call for cooling operation, or can be energized by manual fan switch on subbase for constant air circulation.

Caution: Second stage cooling must always be energized in conjunction with first stage. If the second state were energized alone, the condensate from the upper part of the coil could be blow off or re-evaporated as it passes down over the dry portion of the coil.

HEATING – A thermostat demand for heating makes R-W1 circuit as well as R-G circuit. This starts the indoor blower as well as turns on the electric heater.

SECOND STAGE HEATING (15 KW only) – Circuit R-W2 energizes the second contactor and brings on the last 5 KW of heat.

TABLE 5

INDOOR BLOWER PERFORMANCE

	RATED	1	2	3	4	CFM @ MAX.
				OPTIONAL	CONTINUOUS
MODEL	ESP	MAX. ESP	RATED CFM	CFM	CFM	ESP
QC501	0.0	0.8	1200	1000	1000	1175

NOTE: These units are equipped with a variable speed (ECM) indoor motor that automatically adjusts itself to maintain approximately the same rate of indoor air flow in both heating and cooling, dry and wet coil conditions, and at both 230/208 or 460 volts.

jMaximum ESP (inches WC) shown is with 1” thick disposable filter (reduced by .2 for 2” filter).

kRated CFM for ducted applications – required for maximum performance rating. To obtain full CFM locate low

voltage terminal strip in the circuit breaker box.There is a pink jumper wire with both ends attached to terminal marked “G2”. Move one end of the jumper to terminal“Y”.

lOptional CFM – the unit is shipped from the factory set to operate at the optional CFM level shown.

This provides lower operating sound levels for non-ducted, free discharge applications. This reduces system capacity performance by approximately 2% at the same energy efficiency.

mContinuous fan CFM is the total air being circulated during continuous fan mode.

Manual 2100-416

Page 21