COMPONENTS TESTING

THERMOSTAT (“EQ08” Models) (See Figure 17)

This thermostat is single pole-double throw, cross ambient with a range of 60° to 92°F and a differential of ±2°F. Terminal “2” is common.

Figure 17

Thermostat

(EQ Model)

WARNING

ELECTRIC SHOCK HAZARD

Disconnect power to the unit before servicing. Failure to follow this warning could result in serious injury or death.

TEST:

1.Remove leads from thermostat.

2.Turn thermostat knob clockwise to its coldest position.

3.Test for continuity between the two terminals. Contacts should be closed.

4.Turn thermostat knob counterclockwise to its warmest position.

5.Test for continuity - contacts should be open.

NOTE: The thermostat must be within the temperature range listed to open and close.

To maintain the comfort level desired, a cross ambient type thermostat is used. The thermostat has a range from 60° ±2°F to 92° ±3°F. The thermostat bulb is positioned in front of the evaporator coil to sense the return air temperature. Thermostat malfunction or erratic operation is covered in the troubleshooting section of this manual.

THERMOSTAT - Models ES, YS, EM, YM, EL, YL

A cross ambient thermostat is used on all heat pump and electric heat units. In addition to cycling the unit in a heating or cooling operation, the thermostat will terminate the cooling cycle in the event ice forms on the evaporator coil, in this case the thermostat functions as a de-ice control. A resistor (anticipator) is positioned within a plastic block to supply a small amount of heat to the bulb area to prevent long “off cycles” in the “Cool-Fan Auto” (MoneySaver) position. A current feedback through the fan motor windings during “off cycle” completes the circuit to the resistor.

In the heating cycle, the heat anticipator is energized to supply a small amount of heat during the “on” cycle. This will open the contacts in the thermostat prematurely to maintain a closer differential between the “cut in” and “cut out” temperature. The heat anticipator is energized in the heating mode regardless of whether fan is placed in the automatic (MoneySaver) or constant run position.

RANGE:

Thermostat Properties

 

60°F (±2°) to 92°F (±2°)

TEST:

Cooling/Heating Models: Remove wires from thermostat and check continuity between terminal “2” (common) and “3” for cooling. Check between terminals “2” (common) and “1” for heating. Also check that contacts in thermostat open after placing in either position. NOTE: Temperature must be within range listed to check thermostat. Refer to the troubleshooting section in this manual for additional information on thermostat testing.

THERMOSTAT ADJUSTMENT

No attempt should be made to adjust thermostat. Due to the sensitivity of the internal mechanism and the sophisticated equipment required to check the calibration, it is suggested that the thermostat be replaced rather than calibrated. Thermostat bulb must be straight to insure proper performance.

Figure 18

Thermostat

THERMOSTAT BULB LOCATION

The position of the bulb is important in order for the thermostat to function properly. The bulb of the thermostat should be located approximately 45° to a maximum of 60° from horizontal. Also, do not allow the thermostat bulb to touch the evaporator coil. (See Figures 17 and 18)

Figure 19

Thermostat Bulb Location

(EQ Model)

Thermostat sensor holder 020 to be positioned between the 4th and 5th and 6th and 7th rows of tubes from the bottom of the coil at dimension shown

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Friedrich 2009, 2008 service manual Components Testing, Thermostat Adjustment, Thermostat Bulb Location
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2009, 2008 specifications

Friedrich 2008 and 2009 represent significant advancements in heating and cooling technology, particularly in the realm of air conditioning systems. Friedrich is known for producing robust and efficient HVAC solutions tailored for both residential and commercial applications. These models are particularly noteworthy for their innovative features and energy-efficient technologies that enhance user comfort and lower operational costs.

One of the main characteristics of the Friedrich 2008 and 2009 models is their emphasis on energy efficiency. Both units are designed to meet or exceed Energy Star standards, which indicates that they use less energy compared to standard models, contributing to greener living solutions. The incorporation of efficient compressors and high SEER (Seasonal Energy Efficiency Ratio) ratings ensures that users save money on their electricity bills while enjoying optimal cooling performance.

The units also feature advanced inverter technology, which allows for variable speed operation. This means that the system can adjust its cooling capacity based on the current temperature needs, resulting in more consistent comfort while reducing wear and tear on the equipment. Additionally, the inverter technology operates more quietly compared to traditional systems, making these models suitable for both home environments and commercial settings.

Friedrich 2008 and 2009 also provide users with enhanced control options. The inclusion of smart technology and Wi-Fi connectivity allows for remote monitoring and temperature adjustments via smartphones or tablets. Users can create schedules, set temperature preferences, and receive maintenance alerts, contributing to a more user-friendly experience.

Moreover, these models are designed with robust construction, featuring durable materials that withstand various weather conditions. Their compact footprint and sleek design make them suitable for window installation, while an array of sizes accommodates spaces of different dimensions.

Additionally, the air filtration systems in Friedrich 2008 and 2009 units improve indoor air quality. They effectively capture dust, allergens, and other particulates, ensuring a healthier environment for occupants.

In summary, Friedrich 2008 and 2009 models stand out for their energy efficiency, innovative inverter technology, smart controls, and robust construction. With a focus on user comfort and environmental responsibility, these models provide reliable solutions for effective heating and cooling in diverse applications.
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