York DM 060, DM072, DM 048, DM 036 warranty Static Resistances, Electric Heater CFM Limitations

036-21502-002-A-0303

TABLE 14: STATIC RESISTANCES

						RESISTANCE, IWG
DESCRIPTION
							CFM
		1000	1200	1400	1600	1800	2000	2200	2400	2600	2800	3000
ECONOMIZER1 2		0.07	0.08	0.09	0.11	0.13	0.15	0.17	0.20	0.23	0.26	0.30
ELECTRIC	5-15KW	0.04	0.05	0.06	0.07	0.08	0.10	0.12	0.14	0.16	0.19	0.22
HEATERS3
	20-30KW	0.06	0.07	0.08	0.09	0.11	0.13	0.15	0.17	0.20	0.23	0.26
BOTTOM DUCT CONNECTIONS1		0.06	0.07	0.08	0.09	0.10	0.11	0.12	0.14	0.16	0.19	0.22
COOLING ONLY2		0.08	0.10	0.12	0.14	0.16	0.18	0.20	0.23	0.26	0.29	0.32

1.Deduct these resistance values from the available external static pressure shown in SUPPLY AIR BLOWER PERFORMANCE Tables.

2.The pressure through the economizer is greater for 100% outdoor air than for 100% return air. If the resistance of the return air duct system is less than 0.25 IWG, the unit will deliver less CFM during full economizer operation.

3.Add these resistance values to the available static resistance values on SUPPLY AIR BLOWER PERFORMANCE Tables.

TABLE 15: ELECTRIC HEATER CFM LIMITATIONS

UNIT MODEL SIZE NOMINAL				MINIMUM SUPPLY AIR CFM
	VOLTAGE
				HEATER SIZE NOMINAL KW
TONS
		5	7	10	15	20	30
	208/230-1-60	1100	1100	1200	1200	1300	-
3	208/230-3-60	1100	1100	1200	1200	1300	-
	460-3-60	-	1100	1200	1200	1300	-
	575-3-60	-	-	1200	1200	1300	-
	208/230-1-60	1300	1300	1300	1300	1300	-
4	208/230-3-60	1300	1300	1300	1300	1300	-
	460-3-60	-	1300	1300	1300	1300	-
	575-3-60	-	-	1300	1300	1400	-
	208/230-1-60	1600	1600	1600	1600	1600	1600
5	208/230-3-60	1600	1600	1600	1600	1600	1600
	460-3-60	-	1600	1600	1600	1600	1600
	575-3-60	-	-	1600	1600	1600	1800
	208/230-1-60	1800	1800	1800	1800	1800	1800
6	208/230-3-60	1800	1800	1800	1800	1800	1800
	460-3-60	-	1800	1800	1800	1800	1800
	575-3-60	-	-	1800	1800	1800	1800

Unitary Products Group 21