Sears EF08B1500A3, EF20N2600A2, EF12F1900A2, EF16J2200A2 Maintenance, Air Flow Check

I Electric Furnace

Changing Motor Speed

The blower motor comes from the factory wired for medium or high speed. To change the blower speed, disconnect the black wire at the blower motor termina! block and reconnect at the de- sired blower speed tap.

Figure 10 I Typical Low Voltage Connections

Installation Instructions

Air Flow Check

For proper system operation, the air flow through the indoor coil should be between 350 and 450 cfm per ton of cooling capacity. The air flow through the unit can be determined by measuring the external static pressure to the unit and selecting the motor speed tap that will most closely provide the required air flow.

1. Set up to measure external static pressure at the supply

and return duct connections (Figure 11).

Thermostat Cooling Only

R

G

Y

W

00 0 OOI)

Outdoor Unit

Y

Y

2.	Drill holes in the ducts for pressure	taps, pitot tubes, or oth-
	er accurate pressure sensing devices.
3.	Connect these taps to a level inclined		manometer or draft
	gauge.
4.	Ensure the coil and filter are clean,	and	all the registers are
	open.
5.	Determine the external static pressure		with the blower op-
	erating.
6.	Refer to the Air Flow Data (Figure	6) table to find the speed
	tap that will most closely provide the required air flow for the
	system.
7.	Refer to Changing the Motor Speed in these instructions if
	the speed tap is to be changed.

W 2 W 1 G Y O H C R 1

Indoor Blower

8. Recheck the external static pressure with the new speed

tap, and confirm speed tap selection.

Thermostat

R

Cooling with Electric Heat

Figure 11 Static Pressure Check

G --

Y

y --

Y

SupplyJ

Outdoor Unit

wOwO! (> ()

Heat Pump with Electric Heat

Staging

Thermostat

R

BL

W

-- y

O

Outdoor Unit

/nedli°rn

Return _

Maintenance

Filters

Filters must be cleaned when they become dirty. Inspect at least once per month. The frequency of cleaning depends upon the hours of operation and the local atmospheric conditions. Clean fil- ters keep unit efficiency high.

Lubrication

The bearings of the blower motor are permanently lubricated.

Condensate Drains

During the cooling season check the condensate drain lines to be sure that condensate is flowing from the primary drain but not from the secondary drain. If condensate ever flows from the sec-

ondary drain the unit should be promptly shut off and the conden- sate pan and drains cleaned to insure a free flowing primary drain.

442 01 2204 01 7L_