Lenox Elite Series, XC14 installation instructions Weigh In

3. Determine if fan needs adjustment

CHECKING AIR FLOW AT INDOOR COIL

Check airflow using the Delta−T (DT) process using the illustration in figure 20.

Temp. of air entering indoor coil ºF

A

Dry−bulb

DT

80	24	24	24	23	23	22	22	22	20	19	18	17	16	15
78	23	23	23	22	22	21	21	20	19	18	17	16	15	14
76	22	22	22	21	21	20	19	19	18	17	16	15	14	13
74	21	21	21	20	19	19	18	17	16	16	15	14	13	12
72	20	20	19	18	17	17	16	15	15	14	13	12	11	10
70	19	19	18	18	17	17	16	15	15	14	13	12	11	10

1. Determine the desired DT

ature using dry bulb (A) and wet bulb (B). DT is the intersect- ing value of A and B in the table (see triangle).

2. Find temperature drop across coil

bulb entering and leaving air temperatures (A and C). Tem- perature Drop Formula: (TDrop) = A minus C.

Wet−bulb ºF 57 58 59 60 61 62 63 64 65 66 67 68 69 70

ference between

		B
C	TDrop
53º	19º
	air flow	air flow	B
DRY			64º
BULB
All temperatures are		INDOOR
		COIL
expressed in ºF

A

72º

DRY

BULB

WET

BULB

the measured TDrop and the desired DT (TDrop–DT) is within +3º, no adjustment is needed. See examples: Assume DT =

15 and A temp. = 72º, these C temperatures would necessi- tate stated actions:

Cº	TDrop	–	DT	=	ºF	ACTION
53º	19	–	15	=	4	Increase the airflow
58º	14	–	15	=	−1	(within +3º range) no change
62º	10	–	15	=	−5	Decrease the airflow

4.Adjust the fan speed crease/decrease fan speed.

Changing air flow affects all temperatures; recheck tempera- tures to confirm that the temperature drop and DT are within +3º.

Figure 20. Checking Indoor Airflow over Evaporator Coil using Delta−T Chart

WEIGH IN

CHARGING METHOD 64ºF (17.7ºC) and Below

CALCULATING SYSTEM CHARGE FOR OUTDOOR UNIT VOID OF CHARGE

If the system is void of refrigerant, first, locate and repair any leaks and then weigh in the refrigerant charge into the unit. To calculate the total refrigerant charge:

Amount specified on nameplate

Adjust amount. for variation in line set length listed on line set length table below.

Total charge

		+		=
			Refrigerant Charge per Line Set Length
			Liquid Line	Ounces per 5 feet (g per 1.5 m)
				adjust from 15 feet (4.6 m) line set*
			Set Diameter
			3/8" (9.5 mm)	3 ounce per 5’ (85 g per 1.5 m)
			*If line length is greater than 15 ft. (4.6 m), add this amount. If
		line length is less than 15 ft. (4.6 m), subtract this amount.
NOTE	Insulate liquid line when it is routed through areas where the surrounding ambient temperature could become higher than the
temperature of the liquid line or when pressure drop is equal to or greater than 20 psig.
NOTE	The above nameplate is for illustration purposes only. Go to actual nameplate on outdoor unit for charge information.

Figure 21. Using HFC−410A Weigh In Method

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XC14 SERIES