Lennox International Inc Merit CBX25UH Series, Lennox Air Handler Changing Blower Speed

BLOWER RELAY	CHANGING BLOWER SPEED
5	BLOWER RELAY	PLASTIC CAPS
	HARNESS
	BLUE (MED)	RED (L0)
2
		BLACK (HI)
		YELLOW (COM)

4-PIN BLOWER CONNECTOR

Figure 13. Changing Blower Speed

NOTE — Refer to wiring diagram located on the unit access panel (or figure 13 above) and blower performance (table 2).

SAll air data measured external to unit with 1 inch non-pleated air filter in place.

SAll factory settings are medium speed except the -48 which is set to low speed from the factory.

SAll data given while air handler is operating with a dry DX coil.

Table 2. CBX25UH Blower Performance (3-Speed PSC) - 240V (CFM @ ESP. - in. W. C.)

Air Handler	Blower Speed	.10” WC	.20” WC	.30” WC	.40” WC	.50” WC
Model
	Low (Red)	510	495	475	420	325
18	Med (Blue)	670	650	630	595	505
	High (Black)	905	865	820	770	705
	Low (Red)	630	625	615	610	580
24	Med (Blue)	885	875	850	820	780
	High (Black)	1130	1100	1070	1010	950
	Low (Red)	900	865	830	780	740
30	Med (Blue)	1075	1060	1030	985	940
	High (Black)	1240	1210	1170	1135	1085
	Low (Red)	1160	1140	1115	1085	990
36	Med (Blue)	1500	1445	1385	1300	1200
	High (Black)	1660	1575	1495	1405	1390
	Low (Red)	1325	1315	1300	1275	1225
42	Med (Blue)	1490	1465	1440	1395	1315
	High (Black)	1820	1770	1690	1600	1500
	Low (Red)	1775	1710	1645	1565	1470
48	Med (Blue)	1995	1895	1800	1685	1560
	High (Black)	2070	1970	1850	1719	1595
	Low (Red)	1675	1630	1580	1520	1450
60	Med (Blue)	1965	1925	1875	1800	1695
	High (Black)	2140	2085	2000	1895	1795

SBlower Performance (CFM vs. ESP inches H2O)

SCooling speeds should not be reduced below factory setting.

SUnits with electric heat approved at 0.5” maximum and medium blower speed minimum.

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CBX25UH SERIES