We get asked a lot………..simply………..”what is it?”
John Proctor 
and Title 24
John Proctor and Proctor Engineering Group have been working with Fieldpiece Instruments to create a better tool for the diagnosis of air conditioning systems in the real world. Proctor’s research exposed the need for tuning air conditioners and prompted the California Energy Commission to add the procedures to California’s Title 24 Building Standards.
John Proctor is a professional engineer, 1965 graduate of MIT, and wrote most of the residential cooling section of Title 24. His knowledge is based on a close
association with journeymen HVAC technicians as well as his research monitoring HVAC systems in homes and commercial buildings across North America.
Proctor’s research confirmed that the vast majority of air conditioners were working well below their designed
efficiency, were experiencing premature failures, and were responsible for customer dissatisfaction as well as expensive call backs. These problems are caused by the widespread use of rules of thumb and incorrect adjustment techniques. His research and the research of others prompted regulators to add manufacturer approved procedures to California’s Title 24.
Proctor concluded that a straightforward system to support and assist technicians in implementing these techniques was needed. This conclusion spawned the
CheckMe!® program, the first third-party computerized quality assurance system for technicians. CheckMe!® is based on a massive data set including:
• over 250,000 operating residential and commercial
A/C systems
• over 1,000 laboratory tests on a wide variety of
makes and models
• thousands of hours of data from monitored units in
homes and businesses
• CheckMe!® is continuously refined with new data.
In 1989, John Proctor founded Proctor Engineering Group to focus on methods of improving air conditioners. The company is based in San Rafael, California and is in continual contact with CheckMe!® certified technicians from coast to coast.
CheckMe!®
The CheckMe!® test is included on model HG2. It is
available for purchase on model HG1.
CheckMe!® is the most advanced real-world method
for troubleshooting A/C systems. It looks at the big
picture to diagnose problems. Superheat, Subcooling,
and Target Evaporator Exit Temperature tests look
at individual performance indicators to determine if
they are within proper range. CheckMe!® looks at the
system as a whole to give a more complete diagnosis.
CheckMe!® saves time and money by quickly diagnosing
a range of potential problems or even multiple problems.
CheckMe!® recommends actions to tune the air
conditioner or heat pump to its optimum with minimal
retests. This leads to even fewer call backs.
The algorithms built into CheckMe!® are based on
the real world servicing of over 250,000 air conditioners.
The testing procedure and accuracy of the diagnosis
have been refined over many years by Proctor Engineering.
The CheckMe!® switch position is a real time-saver
because it can give you a more accurate diagnosis than
looking at individual aspects of the air conditioner.
The CheckMe!® position has diagnoses that will help
you pinpoint problems with the system. Besides providing
better diagnoses, it also checks the test numbers and
warns you if there is a likely testing error. In these cases,
you will want to retake some measurements.
CheckMe!® in the HG2 will analyze with almost
any amount of data. The more information supplied,
the more accurate and comprehensive the diagnoses.
CheckMe!® determines the current state of the equipment.
It is recommended that you pretest before repairs
and post test to confirm the improvement.
CheckMe!® INPUT FORM
Sys Type (System Type): Default: AC (Air Conditioning).
Other selections: H Pump Heat (heat pump in heating mode), H Pump Cool (heat pump in cooling mode) or Geothermal.
Grant and Sys Info:Default: None. Other selections: New, None or a previously created Grant. Unless you are working under a Grant program, usually through a utility or government, then the Grant will remain as None. If you are using this for a grant
proceed to the GRANT section of this manual for more details.
INDOOR UNIT
All temperature and pressure measurements must be taken after the unit reaches steady state (generally 15 minutes of continuous operation).
Metering Device: Default: TXV/EXV. Other selection:
Fixed.
Return DB (dry bulb) and Return WB (wet
bulb):Take measurements very close to or within the return air side of the air handler (not at the return grill since temperatures change by the time the air reaches the indoor coil). Wet the wet bulb sensor (ATWB1) and insert it after 15 minutes of continuous
running. Insert the dry bulb sensor (ATA1) through the same hole. They can be clipped together on the downstream side of the filter if the filter is just before the air handler.
Watch the wet bulb temperature; it will drop and then stabilize. The wet bulb temperature is the stabilized reading. If the sensor starts to dry out, the reading will rise and the wrong temperature will be recorded. If the filter is not directly upstream of the air handler, make small holes in the return plenum just big enough for the probes. Seal any holes before leaving the jobsite.
Supply DB (dry bulb leaving the indoor coil): Measure in the center of the supply plenum. Make a small hole in the supply plenum and insert a calibrated dry bulb thermocouple such as the ATA1 or ATB1. Determine the average air temperature in the
supply plenum.
OUTDOOR UNIT
Refrigerant: Default: R-22. Other selection: R410A.
Rated Amps (rated amperage of the outside unit): This can be found on the nameplate along with the outdoor voltage and the refrigerant.
Target Subcool: Manufacturer’s recommended subcooling for TXV/EXV systems. This varies by manufacturer, and may also change depending on weather conditions. Always charge to the equipment manufacturer’s specifications when available. If no target subcooling is available then the HVAC Guide analyzer will make a conservative estimate.
SL Pressure (suction line pressure): Connect the ASX14 to the suction side service port. Select pressure mode on the ASX14 head. The system must be stabilized before taking the measurements. Enter data manually if you want to get pressure from your gauges. The analysis is only as good as the measurements. The Fieldpiece ASX14 has better resolution than most gauge sets.
SL Temp (suction line temperature): Measure near SL service port (within 6 inches). Use the ATC1, ATC2 or ATC3 to get a good pipe temperature. The clamp should be perpendicular to the pipe and should be` securely seated with the sensor in contact with the suction line. On a package unit make sure you are at least 6 inches away from the compressor and not onthe hot gas discharge line.
LL Pressure (liquid line pressure): Connect the ASX14 to the liquid line service port. Set the accessory head to measure pressure and ensure the reading stabilizes before locking in the reading. Enter data manually if you want to get pressure from your gauges. The analysis is only as good as the measurements.
The Fieldpiece ASX14 has better resolution than most gauge sets. LL Temp (liquid line temperature): Measure near the same location that the LL Pressure was taken. Use the ATC1, ATC2 or ATC3 to get a good pipe temperature. The clamp should be perpendicular to the pipe and should be securely seated with the sensor in contact with the liquid line.
OD Dry Bulb (outdoor dry bulb temperature): Clip a calibrated ATA1 to the inlet of the condenser (typically on the side of the condenser), in the shade if possible. Note that the temperature of the air entering the outdoor coil can be considerably different
than the ambient temperature due to recirculation of air exiting the unit. Determine the average temperature of the air entering the condenser.
Cond Amps Draw (actual condensing unit amp
draw): For a package system this is the total amp draw of the unit. With a factory HG2, use an ACH4 amp clamp and take measurement automatically. To use another amp clamp (such as the SC77) and for HG1s upgraded to an HG2, input this measurement
manually.
TrueFlow® 7
The TrueFlow® meter measures the airflow directly via a grid installed in place of the filter (or other location that has all the indoor unit airflow through it). For more information please visit www.energyconservatory.com.
TrueFlow®: Default: NO. If NO, skip ahead to the
Customer ID. Answering YES unlocks the inputs
for this section.
Nom Ton: Nominal tonnage of the A/C system.
Grid Size: Default: 14 inches. Other selection: 20 inches.
Choose the grid size you are using.
Sup Plen Pres: TrueFlow® system operating pressure with the filter installed and no TrueFlow® grid. This is the normal supply operating pressure (NSOP) and is measured using the static pressure probe included with the TrueFlow® plate.
Flow Pressure: This is the TFSOP and is measured
using the TrueFlow® plate.
Sup Plen Pressure with Grid: TrueFlow® system operating pressure with the filter and the TrueFlow® grid installed. This is the TF SOP and is measured using the static pressure probe included with the TrueFlow® plate.
GRANT FORM
If you are working under a grant you are typically required to track additional information about the system in order to qualify for the tax rebates or other incentives. In parts of the Unites States, CheckMe!® is used to verify that a system is tuned to the highest standards and qualify the work for grants. Air conditioning comprises a significant portion of power consumption in the United States but more importantly is often the cause of peak power usage periods. Grants are often funded by utilities or government agencies in order to reduce the peak electrical power consumption and power infrastructure needed to support that.
In order to participate in these grants, a technician will usually have to work through a third party verifier. Contact your local utility to learn on how to become a grant participant. After you have selected “New” or a pre-existing grant from the list of grants you will be taken to the GRANT FORM. The Grant form allows you to create new grants in accordance with particular specifications.
Grant and Sys Info: Use alpha-numeric characters to manually input and name this grant. Once created you can access this grant for future tests.
Optional Inputs: Optional inputs are inputs that you want to be present on the INPUT FORM for the new grant you have created. These inputs are simply for bookkeeping and are not used for any diagnosis or performance calculations. By turning these to
“Yes” you will see them on the INPUT FORM when this grant is selected.
List of inputs: Indoor Model No. (number), Furnace Model No. (number), ID VOLTS (voltage of indoor unit), ID Full Ld Amps (full load running amperage of indoor unit), Sup Plen Press (supply plenum pressure, static), Ret Plen Press (return plenum pressure,
static), Evap Fan Amp (evaporator Fan amperage), Test (initial or after repair), Outdoor Model No (number), Outdoor Year (year manufactured of the outdoor unit), Outdoor Serial No (serial number of the outdoor unit), OD Volts (voltage of the outdoor unit).
Advanced Tolerances: These are some of the basic error tolerances which the CheckMe! program uses to determine if a system is performing properly. Some grants have different tolerences on parameters such as superheat and airflow. This is where you can adjust the tolerances. By adjusting these numbers you will change the way systems are evaluated by the CheckMe! for this particular grant.
The superheat and subcooling tolerances are: Initial SH Tol (superheat tolerance for initial test), After SH Tol (superheat tolerance for test after repair), Initial SC Tol (subcooling tolerance for initial test), After SC Tol (subcooling tolerance for test after repair). These tolerances apply only when the optional input “Test” is yes.
The airflow tolerances are: Temp SPLIT Tol (maximum allowable difference between target temperature split and actual temperature split), Aflow Min (minimum allowable airflow before a unit is considered to have low airflow) and Aflow Max (maximum
allowable airflow before a unit is considered to have high airflow). Press the SAVE button to save your changes and return to the CheckMe! INPUT FORM.
CheckMe!® Output Form Overview
Press the OUTPUT for the CheckMe!® OUTPUT FORM. The diagnoses and recommendations are listedin order with the most likely diagnosis first. Because all parts of an A/C system are interdependent, changes made to one part of the system can influence other parts of the system. For example, increasing airflow may increase the superheat, which may require adding refrigerant. To be efficient, continually check the superheat and/or subcooling as you make refrigerant charge adjustments. After modifications, allow 15 minutes
to stabilize before your final test.
This is a basic Overview of a single feature of the Fieldpiece® HVACGuide® instrument for more detail or to discuss the capabilities of the instrument visit the store at http://www.instrumetrix.com or call us using the numbers provided in the Contact Us tab at the store.
