Bryant 661C, 661G XIV. Check Charge, Defrost Control SPEED-UP Timing Sequence, XV. Final Checks

3.Restart unit in heating mode, allowing frost to accumulate on outdoor coil.

4.After a few minutes in heating mode, liquid line tempera- ture should drop below closing point of defrost thermostat (approximately 30°F).

5.Short between speed-up terminals with a flat-bladed screw- driver. (See Fig. 11.) This reduces the timing sequence to 1/256th of original time. (See Table 2.)

6.When you hear reversing valve change position, remove screwdriver immediately; otherwise, control will terminate normal 10-minute defrost cycle in approximately 2 sec.

NOTE: Length of defrost cycle is dependent on the length of time it takes to remove screwdriver from test pins after reversing valve has shifted.

7.Unit will remain in defrost for remainder of defrost cycle time or until defrost thermostat reopens at approximately 80°F coil temperature of liquid line.

8.Turn off power to outdoor unit and reconnect fan motor lead to OF2 on control board. (See Fig. 11.)

	OF2
OF1
O	R T2 Y TI DFT	C	TEST 30 50 90
			W1
O
R
W2
Y
C
	CES0110063,
	CES0130024

A91444

Fig. 11—Defrost Control

XIV. CHECK CHARGE

Factory charge is shown on unit rating plate. To check charge in cooling mode, refer to Cooling Only Procedure on unit wiring and charging label. To check charge in heating mode, refer to Heating Check Chart Procedure.

TABLE 2—DEFROST CONTROL SPEED-UP

TIMING SEQUENCE

PARAMETER	MINIMUM	MAXIMUM	SPEED-UP
	(MINUTES)	(MINUTES)	(NOMINAL)
30-minute cycle	27	33	7 sec
50-minute cycle	45	55	12 sec
90-minute cycle	81	99	21 sec
10-minute cycle	9	11	2 sec
5 minutes	4.5	5.5	1 sec

NOTE: If superheat or subcooling charging conditions are not favorable, charge must be weighed in accordance with unit rating plate ± 0.6 oz/ft of 3/8-in. liquid line above or below 15 ft respectively.

A. Heating Check Chart Procedure

To check system operation during heating cycle, refer to the Heating Check Chart on outdoor unit. This chart indicates whether a correct relationship exists between system operating pressure and air temperature entering indoor and outdoor units. If pressure and temperature do not match on chart, system refrigerant charge may not be correct. Do not use chart to adjust refrigerant charge.

NOTE: When charging is necessary during heating season, charge must be weighed in accordance with unit rating plate ± 0.6 oz/ft of 3/8-in. liquid line above or below 15 ft respectively.

EXAMPLE:

To calculate additional charge required for a 25-ft line set:

25 ft - 15 ft = 10 ft X 0.6 oz/ft =6 oz of additional charge

XV. FINAL CHECKS

IMPORTANT: Before leaving job, be sure to do the following:

1.Securely fasten all panels and covers.

2.Tighten service valve stem caps to 1/12-turn past finger tight.

3.Leave User’s Manual with owner. Explain system operation and periodic maintenance requirements outlined in manual.

4.Fill out Dealer Installation Checklist and place in customer file.

CARE AND MAINTENANCE

For continuing high performance and to minimize possible equip- ment failure, periodic maintenance must be performed on this equipment.

Frequency of maintenance may vary depending upon geographic areas, such as coastal applications.

© 2002 Bryant Heating & Cooling Systems 7310 W. Morris St. Indianapolis, IN 46231 —8— Printed in U.S.A. 661c187 Catalog No. 5366-119