Carrier PTV, 50PTH specifications Blower Performance Data

Table 13 — Blower Performance Data

50PT	MAX ESP	FAN	TAP	COOLING MODE (cfm)			DEHUMIDIFICATION MODE (cfm)			HEATING MODE (cfm)
		MOTOR
UNIT SIZE	(in. wg)		SETTING	Stage 1	Stage 2	Fan	Stage 1	Stage 2	Fan	Stage 1	Stage 2	Fan
		(hp)
			4	810	950	475	630	740	475	920	1060	475
026	0.50	1/2	3	725	850	425	560	660	425	825	950	425
			2	620	730	370	490	570	370	710	820	370
			1	520	610	300	—	—	—	600	690	300
			4	1120	1400	700	870	1090	700	1120	1400	700
038	0.50	1/2	3	1000	1250	630	780	980	630	1000	1250	630
			2	860	1080	540	670	840	540	860	1080	540
			1	730	900	450	—	—	—	730	900	450
			4	1460	1730	870	1140	1350	870	1560	1850	870
049	0.75	1	3	1300	1550	780	1020	1210	780	1400	1650	780
			2	1120	1330	670	870	1040	670	1200	1430	670
			1	940	1120	560	—	—	—	1010	1200	560
			4	1670	2050	1020	1300	1600	1020	1860	2280	1020
064	0.75	1	3	1500	1825	920	1160	1430	920	1650	2050	920
			2	1280	1580	790	1000	1230	790	1430	1750	790
			1	1080	1320	660	—	—	—	1200	1470	660
			4	1620	2190	1050	1270	1650	1050	1690	2230	1050
072	0.75	1	3	1500	1950	980	1170	1520	980	1600	2100	980
			2	1400	1830	910	1100	1420	910	1400	1850	910
			1	1320	1700	850	—	—	—	1240	1620	850

WSHP OPEN CONTROLS — The ECM fan is controlled by an interface board that converts the fan speed outputs from the WSHP Open control board to the signal used by the ECM mo- tor (see Fig 35). The indicator LEDs allow the service techni- cian to view the airflow mode that the WSHP Open control is commanding. The table below indicates the illuminated LEDs for each fan mode.

ECM INDICATORS LEDs	SPEED
G	Fan Only
G + Y1	Low Fan
G + Y1 + Y2	Med Fan
G + Y1 +W	High Fan

NOTE: Power must be off to the unit for at least three seconds before the ECM will recognize a speed change. The motor will recognize a change in the CFM Adjust setting (SW7 and SW8) while the unit is powered.

The WSHP Open controller provides four different airflow settings which can be set between the lowest airflow (tap 1) to the highest airflow (tap 4). The lowest three airflow settings (Fan Only, Low, and Medium) are set using SW3 and SW 4 while the highest airflow (High) is set independently using SW5 and SW6. This provides the ability to better adjust the fan performance of the unit to meet the required load conditions.

Cooling and Heating — The SW3 and SW4 DIP switch set- tings determine the fan airflow (cfm) to be used during normal Fan Only, Cooling, Heating, and Dehumidification modes (see

Table 14A). The fan speed and airflow is independent from the compressor capacity control. During Fan Only operation, the fan will operate at the Fan Only airflow value specified in the table for the appropriate tap setting. Once either cooling or heating is required and the compressor is energized, the fan will increase the minimum airflow across the coil to the value defined by the low fan selection. Coil freeze protection and ex- cessive discharge air temperature protection are integral parts of the WSHP Open controller function so the fan airflow can increase to medium or high airflow as required and indepen- dent of compressor capacity to prevent excessively hot or cold supply air temperature and coil freeze-up. The selection of the high fan airflow setting is independent of the other fan airflow settings and is defined in Table 14B. The high airflow must be chosen so that it is equal to or greater than the medium fan air- flow. Therefore the tap setting for high fan (SW5 and SW6) MUST equal or exceed the tap chosen for the SW3 and SW4.

Dehumidification — When Dehumidification is used, the fan operates at the airflow setting defined by the Medium Fan air- flow setting and the tap position of SW3 and SW4.

CFM Adjust — The CFM Adjust setting allows the balancer to fine tune the actual airflow. SW7 and SW8 are used to set the CFM Adjustment if necessary. The NORM setting is the factory default. The (+) or (-) settings provide the ability to ad- just the airflow by either +15% or -15% as needed. A test posi- tion is also provided but should not be used (see Table 11).

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