Thermal Engineering 14101E Installation Manual

MODEL 14101E OPERATING INSTRUCTIONS

INSTALLING BATTERY

Slide OFF-ON-BAT TEST switch to OFF position. Failure to turn switch to OFF when installing battery
may cause damage to the instrument. Install 9-volt battery. Test battery by moving the OFF-ON-BAT
TEST switch to the BAT TEST position. The lower scale indicates the batteries condition.

MEASURING TEMPERATURE

Insert thermocouple probe into jack #1. Push in probe selector button #1. Slide the OFF-ON-BAT TEST
switch to ON and select the appropriate temperature range. Meter will now display temperature at the tip of
the probe. To use probe positions #2, #3 or #4 select the appropriate button.

NOTE: The instrument indicates the approximate ambient temperature of the panel when a probe position
is selected and a thermocouple probe is not plugged in.

MEASURING TEMPERATURE DIFFERENTIAL

Insert probes into jacks #1 and #2 and push the gray TD button. The instrument indicates the temperature
difference between probes #1 and #2. If the temperature at probe #2 is greater, the temperature difference
will be negative. Use the -50°F (-30°C) to +50°F (+30°C) range for temperature differential.

SPECIFICATIONS

Range: -50° to 150°F, -46° to 66°C

-50° to 600°F, -46° to 316°C

-50° to 1500°F, -46°to 760°C TD -50° to 150°F,

(-30°C) to (+30°C) Accuracy ± 3% of full scale range

SYSTEM TEMPERATURES

A good service technician uses every possible bit of information available from a system to determine the
diagnosis.

Two of the most informative measurements around the refrigeration cycle are the refrigerant temperatures
at the inlet and outlet of the evaporator. The difference between these two is a good approximation of
superheat. The inlet temperature is the true coil refrigerant temperature which should be about 10°F (6°C)
below the design temperature in the area being cooled.

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The different temperatures of the air coming off the evaporator and condenser are also important
troubleshooting indicators. The temperature drop across the evaporator is the best measure of
dehumidification.

The condenser inlet and outlet temperatures are very informative. Actual condensing temperature and high
side pressure measurements compared to design measurements can reveal a great deal of information. For
example, CFC-12 systems with a condensing temperature of 115°F should have a corresponding pressure
of 150 PSI. For HCFC-22 systems, the corresponding numbers are 115°F and 250 PSI.

Remember that the example uses ideal, or perfect, measurements. Rarely, if ever, are these numbers seen
in field applications. Ambient conditions vary widely and every application is different. This is particularly
true when dealing with refrigerant blends.

SUPERHEAT

Superheat is an extremely important concept in refrigeration service. It measures the efficiency of the
evaporator as well as protects the compressor. A service technician must understand what superheat is and
how to determine the best setting.

Heat from a conditioned space or object is absorbed by the cold liquid refrigerant as ft travels through the
evaporator. When all the liquid has been changed into vapor, or boiled off, no more cooling occurs. To
make full use of the evaporator, refrigerant must be boiling throughout the entire coil.

In a perfect system the extremely saturated (part liquid, part vapor) refrigerant that exits the metering
device begins to boil at the very beginning of the coil. By the time it reaches the end of the evaporator it is
100% vapor. In other words, superheat would be equal to 0°.

Although 0° superheat is the most efficient setting some liquid could travel to the compressor. Liquid
refrigerant damages compressors so efficiency cannot be the only factor. Additional heat must be absorbed
by the evaporator to ensure that there is 100% vapor before the refrigerant continues to the compressor.
This is superheat.

Superheat settings vary with each system. The ideal is 0°F (0°C) and 20°F (11°C) is generally accepted as
the very highest setting. Aim for a setting between 10° (6°C) and 15°F (8°C). Remember that as superheat
increases evaporator efficiency decreases. The goal, then, is to keep efficiency at its maximum while
ensuring compressor safety.

THERMAL ENGINEERING COMPANY

A Division of Airserco Manufacturing Company LLC

7555 Tyler Boulevard; Mentor, OH 44060 800-473-1754 Fax: [phone]

www.thermalengineeringcompany.com

MEASURING SUPERHEAT

THE TEMPERATURE-PRESSURE METHOD

This method requires the use of a manifold gauge set and Model 14101E Thermometer.

At the evaporator outlet measure the pressure and read the corresponding temperature on the manifold
gauge. Now measure the actual temperature at the outlet using Model 14101E. The difference between the
two temperatures is superheat

Example: Pressure reading: 29PSI (CFC-12)
Corresponding temperature 30°F (-1°0)
Measured temperature 40°F (4°C)
40°-30°=10° (5°C) Superheat

THE TWO-TEMPERATURE METHOD

This method requires only the use of Model 14101E Digital Thermometer.

Measure the temperature at the evaporator inlet. Measure the temperature at any point along the suction line
as close to the evaporator outlet as possible. Comparison of these two numbers will provide a good
approximation of the superheat and is adequate for most systems.

Example: Evaporator inlet 45°F (7°C) Evaporator outlet 29°F (-2°C)
45° - 29° =16° (9°C) Superheat

Model 14101E’s temperature differential (TD) function can speed up the process. Attach Probe #2 to the
evaporator inlet and Probe #1 to the suction line as close as possible to the evaporator outlet. Press the gray
TD button and the superheat will read automatically. This is a great feature when setting a thermostatic
expansion valve (TXV).

SUB COOLING

The purpose of a condenser is to reject heat from a conditioned space or object to another area. When heat
is rejected the refrigerant changes from a vapor to a liquid. For optimum efficiency all the refrigerant must
be liquid by the time it leaves the condenser before traveling to the metering device.

To insure the change is complete the amount of sub cooling is calculated. No sub cooling may indicate a
low charge or a heavily increased load where the metering device is calling quickly for extra refrigerant
Sub cooling measurements above 10°F (8°C) indicates a restriction. Sub cooling should be measured
between 3° (2°C) and 8V(5°C).

THERMAL ENGINEERING COMPANY

A Division of Airserco Manufacturing Company LLC

7555 Tyler Boulevard; Mentor, OH 44060 800-473-1754 Fax: [phone]

www.thermalengineeringcompany.com

THE TEMPERATURE-PRESSURE METHOD

This method requires the use of a manifold gauge set and Model 14101E Thermometer.

At the condenser outlet measure the pressure and read the corresponding temperature on the manifold
gauge. Now measure the actual temperature at the outlet using Model 14101E. The difference between the
two temperatures is sub cooling.

Example: Pressure reading: 168PSI (HCFC-22)
Corresponding temperature 90°F (32°C)
Measured temperature 86°F (30°C)
9(T-86«=4»(2«C) Sub cooling

THE TWO TEMPERATURE METHOD

This method requires only the use of Model 14101E Thermometer.

Measure the temperature halfway through the condenser. Measure the temperature at the condenser outlet
Comparison of these two numbers will provide a good approximation of the sub cooling.

Example: Condenser halfway point 107°F (42°C)
Condenser outlet 100°F (38°C)
107° -100° = 7° (4°C) Sub cooling

Model 14101Es temperature differential (TD) function can speed up the process. Attach Probe #2 at the
condenser halfway point and Probe #1 to the condenser outlet Press the gray TD button and the sub cooling
will read automatically.

THERMAL ENGINEERING COMPANY

A Division of Airserco Manufacturing Company LLC

7555 Tyler Boulevard; Mentor, OH 44060 800-473-1754 Fax: [phone]

www.thermalengineeringcompany.com

Model 14101E Field Calibration Procedure

1. Turn instrument off and remove it from case.

2. Allow the instrument to stabilize to the ambient temperature.

3. Located on the vertical printed circuit board are two adjustment trim pots. See diagram below for

trim pot description.

4. Install a new battery.

5. Plug thermocouple probes into jacks #1 and #2 (labeled TD).

6. Turn instrument on for a few minutes before calibrating.

7. Prepare two reference temperatures consisting of ice water and boiling water.

Important: The ice water should consist of well stirred crushed ice and a small amount of water. Frequent
stirring is necessary to maintain 32°F(0°C).

• Proceed in the following order for proper calibration.

1. Attach the measuring ends of probes 1 and 2 together so they both measure the same temperature

(ambient is adequate).

2. Push the probe select button label TD.

0

3. Adjust the TD adjust trim pot until the meter reads 0 on -SO

to +50°F or 0 on the -30°C to +30°C

scale.

4. Separate probes 1 and 2 and place measuring ends of probe 1 into the ice water and probe 2 in the

boiling water. Important stir crushed ice and water frequently.

5. Set range to 150°F (66°C) range. '

6. Select probe #1 by pressing the appropriate push button.

7. Adjust the temperature trim pot until the meter reads 32°F (0°C).

8. Set range to 600°F (316°C) range

9. Select probe #2 pressing the appropriate push button.

10. The meter should read 212°F (100°C) +/- %3.

THERMAL ENGINEERING COMPANY

A Division of Airserco Manufacturing Company LLC

7555 Tyler Boulevard; Mentor, OH 44060 800-473-1754 Fax: [phone]

www.thermalengineeringcompany.com

REPAIR INFORMATION

PROBE REPAIR

The thermocouple probe can be repaired in the field. To repair the plug end of the thermocouple, unscrew
the cover to the plug. Strip back the outer insulation ½" exposing a white and red wire. Connect the white
wire to the positive screw on the plug. Connect the red wire to the negative screw. To repair the sensing tip,
strip back the outer and inner insulation ¼" to expose the two bare wires. Twist wires together and solder
the connection using rosin core solder (do not use acid core solder).

REPLACEMENT ACCESSORIES

o D4109 Low temperature thermocouple probe (-40° to 220°F) (-40º to 104ºC)

o D4111 High temperature thermocouple probe (-40º to 1400°F) (-40º to 760ºC)

o D4113 25 ft thermocouple extension

o D4115 High temperature

o D4111 Immersion probe

o 14116 Flexible probe damp

THERMAL ENGINEERING COMPANY

A Division of Airserco Manufacturing Company LLC

7555 Tyler Boulevard; Mentor, OH 44060 800-473-1754 Fax: [phone]

www.thermalengineeringcompany.com