The SRH2 is a complete digital psychrometer and a very valuable HVAC diagnostic tool. As a psychrometer, it measures wet bulb (WB), dry bulb (DB), percent relative humidity (RH%), and dew point (DP). As a diagnostic tool, it helps the HVAC technician easily diagnose problems with air flow across the evaporator. It can also calculate the target superheat of a fixed restrictor air conditioning system.
The SRH2 Diagnostic Psychrometer is an easy to use hand-held diagnostic instrument that performs the normal functions of a digital psychrometer plus it calculates critical air conditioning system targets from psychrometric measurements.
- Measures temperature (DB) and %relative humidity (%RH)
- Calculates wet bulb (WB) and dew point (DP)
- Calculates Target Superheat (TSH)
- Calculates Target Evaporator Exit Temp (TEET) (aka - delta T, temp split)
- Only digital psychrometer that takes measurments using an electronic sensor (NTC) or k-type thermocouples (T/C)
How Does it Work?
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Normal Mode (NORM).
For use as a normal digital psychrometer press the TSH/TEET/NORM button until NORM is displayed on the screen. Select the NTC sensors for quick accurate readings electronically.
Target Superheat Mode (TSH).
Target superheat (TSH) is the first step in determining charge on a fixed orifice system. Compare your TSH to your ACTUAL superheat to determine whether refrigerant needs to be added or recovered. Up until now you had to take the measurements, find a target superheat chart and find the target. Now the chart is in you meter. ENTER your outdoor dry bulb, ENTER indoor wet bulb, press OUTPUT and your TSH is displayed.
To get started, press the TSH/TEET/NORM until TSH (target superheat) is displayed on the screen.
The easy way.
For indoor wet bulb, use the NTC and press RH/DP/WB/DB until ID (indoor) and WB are displayed on the screen. For outdoor dry bulb measurements use the NTC and press the RH/DP/WB/DB button until DB is displayed. Let reading stabilize and press enter to lock it in.
For even more accurate readings.
Use the included wet and dry bulb thermocouples. Wet and clip the ATWB1 T/C to the return air filter and push the filter back in line. Select T/C and ID WB using the RH/DP/WB/DB button. Clip the ATA1 beaded T/C to the condenser and make sure T/C, OD, and DB are displayed.
Target Evaporator Exit Temperature Mode (TEET)
Target Evaporator Exit Temperature is also called delta T, temp split, temp drop across the coil. Whatever you call it, TEET is an important first step in diagnosing capacity and airflow problems.
To get started, press the TSH/TEET/NORM until TEET is displayed on the screen.
Wet the ATWB1. Clip both the included wet and dry bulb T/Cs to the return air filter and push the filter back in line. Plug the ATWB1 into the top of the meter. Press RH/DP/WB/DB until WB is displayed. Press SENSOR until T/C is displayed. When reading is stable, press ENTER. Unplug the ATWB1 and plug in the ATA1. Press RH/DP/WB/DB until DB is displayed. Press SENSOR until T/C is displayed. When reading is stable, press ENTER. Press OUTPUT to get your TEET.
Take a dry bulb measurment in the supply air after the evaporator to get your ACTUAL Evap. Exit Temp. Compare to your TEET reading. An ACTUAL Evap. Exit Temp. above the TEET usually indicates low capacity. Occasionally airflow is higher than expected. Look for causes of low capacity such as refrigerant mischarge or a dirty condenser coil. If the airflow is high, correct it by lowering the fan speed.
Competitive Advantages.
There are other digital psychrometers on the market. None are like the SRH2!
- DIGITAL PSYCHROMETER PLUS DIAGNOSTIC TESTING: Target Superheat, Target Evaporator Exit Temperature tests included. Most psychrometers only give you Temp, %RH, WB, and Dew Point.
- TWO SENSORS: The SRH2 is the only psychrometer that uses either k-type thermocouples or a NTC for testing. You decide how you want to use it. The thermocouple advantage gets you into places other digital psychrometers can't go.
- RUGGED: The SRH2 is built like all of our hand-held meters. Ruggedized for the type of punishment testing in the field can dish out.
- COMPETITIVE PRICE: The SRH2 Diagnostic Psychrometer is competitively priced with "normal" digital psychrometers. You deserve the diagnostics with your psychrometer, so we include them.
- ERGONOMIC DESIGN: The SRH2 fits easily in your hand because it uses our ergonomic hand-held design. Other testers fit in your hand too, but you'll need your other hand for all of the charts, notepads and a calculator.
- MADE FOR TECHS WITH TECHS: As with all of our instruments, the SRH2 Diagnostic Psychrometer was developed with you, the HVAC/R technician, in mind to make your job easier, faster and more efficient. Thanks to all who tested with us in the field.