Friedrich A-SERIES manual III. Chassis Operation, IV. Service & Warranty

920-075-08

III. Chassis Operation

9) Remote Thermostat Control

The chassis requires a simple single stage heat-cool wall thermostat. Each chassis comes with a terminal strip located in the electrical control box. All internal chassis wiring (low & high voltage) is factory ready for 230 Volt operation. For 208 Volt operation a single wire MUST BE CHANGED ON THE TRANSFORMER. Refer to Figure 7 on page 9.

10) Low Ambient Protection

Each chassis is equipped with Low Ambient Protection in the form of a suction line thermostat. This thermostat will prevent compressor operation at low suction line temperatures. Each chassis is also equipped with a factory installed bellows that will drain water from the base pan to prevent the fan slinger from freezing during winter weather.

11)Heating Defrost (Heat Pump Models Only)

All Heat Pumps have a passive heating defrost system. Defrost occurs as needed and automatically switches to electric heat during defrost. When the outdoor ambient temperature drops below a 45°F factory setting, the chassis automatically switches to electric heat. As outdoor ambient temperatures rise above 45°F, the chassis returns to the heat pump mode. The changeover temperature is user adjustable from approximately 32°F - 55°F. The defrost thermostat may also be used to lock out the compressor in an emergency heat situation.

12) Fresh Air Door

The Fresh Air Door is an "intake" system. The fresh air door is opened via a slide on the front of the chassis located just above the indoor coil. Move the slide left to open and right to close the fresh air door. The system is capable of up to 60 CFM of fresh air @ ~.3" H20 internal static pressure.

Follow all codes when working with the condensate drain system. A secondary drain pan may be placed beneath the chassis to prevent condensated spillage due to improper installation or unit malfunction.

IV. Service & Warranty

14) Servicing / Chassis Quick Changeouts

The chassis is designed for quick disconnect and change out. For minor electrical service, the control box cover lifts straight up after the screws & disconnect head are removed. For major electrical, refrigeration and fan service the chassis must be removed from utility closet.

To Remove the Chassis from the Closet:

ASwitch the wall thermostat off.

BPull the power disconnect located in the front of the chassis.

CTurn off all power to the unit at the main breaker or disconnect.

DDisconnect the thermostat wiring.

EDisconnect the electrical connection.

FDisconnect the ductwork.

GDisconnect the drain connection.

HSlide the chassis out of the wall plenum.

I Lift the chassis out of the utility closet.

15) Warranty

All service work must be done by a qualified servicer. See Warranty on the next page, and consult your dealer or contractor for details.

13) Condensate Disposal System

The internal drain connections are 3/4" FPT fittings on the right, left and outdoor side of the unit. See Figure 10 on page 12. The chassis is designed with a condensate drain system that has 3 parts. The three parts work as follows:

Part 1: The system’s first stage increases energy efficiency utilizing a factory installed fan that slings the cold condensate onto the hot outdoor coil.

Part 2: When high outdoor humidity prevents the slinger from disposing of all the condensate, the excess condensate overflows into the internal drain connection.

Part 3: If Parts 1 & 2 fail for any reason, excess condensate overflows from a spillway directly into the wall plenum to the outside of the building. IF THIS OCCURS, THIS IS YOUR WARNING THAT THE CHASSIS OR DRAIN NEEDS SERVICING.

Electrical shock and moving parts hazard can cause injury or death. Pull out the disconnect head found on the front of the chassis before servicing.

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