Goodman Mfg IO-367B Three Phase Models Only, Belt Drive, t = Span length, inches

System Voltage - That nominal voltage value assigned to a circuit or system for the purpose of designating its voltage class.

Nameplate Voltage - That voltage assigned to a piece of equipment for the purpose of designating its voltage class and for the purpose of defining the minimum and maximum voltage at which the equipment will operate.

Utilization Voltage - The voltage of the line terminals of the equipment at which the equipment must give fully satisfac- tory performance. Once it is established that supply voltage will be maintained within the utilization range under all sys- tem conditions, check and calculate if an unbalanced condi- tion exists between phases. Calculate percent voltage un- balance as follows:

Three Phase Models Only

		2) MAXIMUM VOLTAGE DEVIATIONS
3) PERCENT VOLTAGE	= 100 X		FROM AVERAGE VOLTAGE
UNBALANCE			1) AVERAGE VOLTAGE

HOW TO USE THE FORMULA:

EXAMPLE: With voltage of 220, 216, and 213

1)Average Voltage = 220+216+213=649 / 3 = 216

2)Maximum Voltage Deviations from Average Voltage = 220 - 216 = 4

3) Percent Voltage Unbalance = 100 x	4	=	400	= 1.8%
	216		216

Percent voltage unbalance MUST NOT exceed 2%.

FIELD DUCT CONNECTIONS

Verify that all duct connections are tight and that there is no air bypass between supply and return.

FILTER SECTION CHECK

Remove filter section access panels and check that filters are properly installed. Note airflow arrows on filter frames.

BELT DRIVE

BEARING CHECK

Prior to energizing any fans, check and make sure that all setscrews are tight so that bearings are properly secured to shafts.

For heat pump units, the airflow must be adjusted so that the air temperature rise falls within the ranges given stated on Data Plate (see Appendix A - Blower Performance).

NOTE: Section on high static tables may require a field motor change.

TENSION AND ALIGNMENT ADJUSTMENT

Correct belt tension is very important to the life of your belt. Too loose a belt will shorten its life; too tight, premature mo- tor and bearing failure will occur. Check you belt drive for adequate “run-in” belt tension by measuring the force required to deflect the belt at the midpoint of the span length. Belt tension force can be measured using a belt tension gauge, available through most belt drive manufacturers.

t = Span length, inches

C = Center distance, inches

D = Larger sheave diameter, inches d = Smaller sheave diameter, inches

h = Deflection height, inches

DRIVE BELT TENSION ADJUSTMENT

	TYPE		SHEAVE	DEFLECTION		DEFLECTION
				FORCE (lbs)
MODEL			DIAMETER
						(in)
			(in)
	BELT	DRIVE		Used	New
15 Ton	B, BX	Standard	4.3 to 5.5	5.5 + .5	8.2 + .5	1/4 ± 1/16
15 Ton	B, BX	High	4.3 to 5.5	5.5 + .5	8.2 + .5	1/4 ± 1/16
		Static
20 Ton	B, BA	Standard	4.3 to 5.5	5.5 + .5	8.2 + .5	1/4 ± 1/16
20 Ton	B, BA	High	4.3 to 5.5	5.5 + .5	8.2 + .5	1/4 ± 1/16
		Static

RECOMMENDED POUNDS OF FORCE PER BELT

New V-belts will drop rapidly during the first few hours of use. Check tension frequently during the first 24 hours of opera- tion. Tension should fall between the minimum and maximum force. To determine the deflection distance from a normal position, measure the distance from sheave to sheave using a straightedge or a cord. This is your reference line. On mul- tiple belt drives, an adjacent undeflected belt can be used as a reference.

EVAPORATOR FAN ROTATION CHECK (THREE PHASE MODELS ONLY)

Check that fan rotates clockwise when viewed from the drive side of unit and in accordance with rotation arrow shown on blower housing. If it does not, reverse the two incoming power cables at Single Point Power Block. In this case, repeat bear- ing check.

Do not attempt to change load side wiring. Internal wiring assures all motors and compressors will rotate in correct di- rection once evaporator fan motor rotation check has been made.

ELECTRICAL INPUT CHECK

Make preliminary check of evaporator fan ampere draw and verify that motor nameplate amps are not exceeded. A final check of amp draw should be made upon completion of air balancing of the duct system (see Appendix C).

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