York DFAA Applying Filter Pressure Drop To, Determine System Airflow, Final Procedure, UIM-B-1105

										107272-UIM-B-1105
APPLYING FILTER PRESSURE DROP TO				Multiply percentage by airflow difference to obtain airflow reduction.
DETERMINE SYSTEM AIRFLOW				(0.5) X (-65) = -32.5
Example: For a 84,000 BTUH (38.06 kW) furnace with 1 return open-				Subtract airflow reduction value to airflow @ 0.10 w.c. (125 Pa) to
ings and operating on high-speed blower, it is found that total system				obtain actual airflow @ 0.30 wc (144 Pa) ESP.
static is 0.30” w.c. (0.075 kPa). To determine the system airflow, com-				1050 - 32.5 = 1017.5
plete the following steps:
				FINAL PROCEDURE
Obtain the airflow values at 0.10 w.c. (125 Pa) & 0.20 w.c. (150 Pa)
ESP.				Install Furnace Doors
Airflow @ 0.10”: 1175 CFM (60.17 m3/min)				Install the lower door first by sliding the bottom of the door down until
Airflow @ 0.20”: 1110 CFM (57.62 m3/min)				the tabs on the casing base engage the slots in the bottom door end
Subtract the airflow @ 0.10 w.c. (125 Pa) from the airflow @ 0.20 w.c.				cap. Then push the top of the lower door in until the door clips snap into
				place. Install the upper door in a similar manner, first engaging the slots
(150 Pa) to obtain airflow difference.
1175 - 1110 = -65 CFM (2.55 m3/min)				in the top of the upper door on the tabs on the casing top. Then snap
				the bottom of the upper door into place against the casing.
Subtract the total system static from 0.10 w.c. (125 Pa) and divide this
				Finish and Trim
difference by the difference in ESP values in the table, 0.20			w.c.
(150 Pa) - 0.10 w.c. (125 Pa), to obtain a percentage.				Alcove and Closet Installations may now be finished and trimmed as
(0.30 - 0.10) / (0.20 - 0.10) = 0.5				necessary.
TABLE 14: Blower Performance CFM
	BLOWER PERFORMANCE CFM - DFAA066
	FACTORY EQUIPPED WITH STANDARD BLOWERS AND FILTERS
				EXTERNAL STATIC PRESSURE, INCHES WC (kPa)
Blower Speed	BTU/H (kW)	CFM	0.1 (0.025)		0.2 (0.050)		0.3 (0.075)		0.4 (0.099)		0.5 (0.124)
	Input / Output	(m3 / min)
			cfm	cm/m	cfm	cm/m	cfm	cm/m	cfm	cm/m	cfm	cm/m
Single Speed - No Coil	66(19.34) / 53(15.55)	1050(29.73)	1175	33.3	1110	31.4	1050	29.7	1000	28.3	950	26.9
Single Speed - With Dry Coil	66(19.34) / 53(15.55)	1050(29.73)	1125	31.9	1070	30.3	1020	28.9	960	27.2	910	25.8
		BLOWER PERFORMANCE CFM - DFAA084
				EXTERNAL STATIC PRESSURE, INCHES WC (kPa)
Blower Speed	BTU/H (kW)	CFM	0.1 (0.025)		0.2 (0.050)		0.3 (0.075)		0.4 (0.099)		0.5 (0.124)
	Input / Output	(m3 / min)	cfm	cm/m	cfm	cm/m	cfm	cm/m	cfm	cm/m	cfm	cm/m
Single Speed - No Coil	84(24.62) / 67(19.63)	1250(35.39)	1370	38.8	1305	37.0	1245	35.3	1175	33.3	1100	31.1
Single Speed - With Dry Coil	84(24.62) / 67(19.63)	1250(35.39)	1265	35.8	1195	33.8	1120	31.7	1045	29.6	1015	28.7
		BLOWER PERFORMANCE CFM - DFAH066
				EXTERNAL STATIC PRESSURE, INCHES WC (kPa)
Blower Speed	BTU/H (kW)	CFM	0.1 (0.025)		0.2 (0.050)		0.3 (0.075)		0.4 (0.099)		0.5 (0.124)
	Input / Output	(m3 / min)
			cfm	cm/m	cfm	cm/m	cfm	cm/m	cfm	cm/m	cfm	cm/m
Single Speed - No Coil	66(19.34) / 53(15.55	1050(29.73)	1155	32.7	1111	31.5	1055	29.9	995	28.2	920	26.1
		BLOWER PERFORMANCE CFM - DFAH084
				EXTERNAL STATIC PRESSURE, INCHES WC (kPa)
Blower Speed	BTU/H (kW)	CFM	0.1 (0.025)		0.2 (0.050)		0.3 (0.075)		0.4 (0.099)		0.5 (0.124)
	Input / Output	(m3 / min)	cfm	cm/m	cfm	cm/m	cfm	cm/m	cfm	cm/m	cfm	cm/m
Single Speed - No Coil	84(24.62) / 67(19.63)	1250(35.39)	1127	31.9	1062	30.1	1005	28.5	952	27.0	887	25.1
NOTES:

1.Airflow expressed in standard cubic feet per minute (cfm) and in cubic meters per minute (cm/m)

2.Return air is through louvered filter door only.

3.Motor voltage at 115V

Unitary Products Group 25