Startup record
How to Read a Geothermal Commissioning Record
Direct answer: a geothermal commissioning record is the baseline proof that the installed system was started, purged, pressurized, flowed, and checked under known conditions. It should record equipment, loop type, fluid, antifreeze, EWT, LWT, PSI, pressure drop, calculated or measured GPM, pump settings, operating mode, and any manufacturer startup checks.
This page does not duplicate an EWT/LWT/GPM troubleshooting guide. It explains how to interpret the startup record that should exist before future diagnostics begin.
Definitions
Commissioning
The startup verification process that records whether the installed system matches its design and manufacturer requirements.
P/T Ports
Pressure/temperature ports used to measure water-side temperature and pressure drop at the heat pump or other components.
Baseline
The first known-good record for future comparison. A baseline is only useful when operating mode and conditions are documented.
What The Record Should Include
| Record item | Why it matters | How to read it |
|---|---|---|
| Equipment model and mode | Startup readings mean different things in heating, cooling, first stage, second stage, or water-heating mode. | Never compare readings without operating mode. |
| EWT and LWT | Temperature split helps confirm heat transfer and flow context. | Compare to design expectation and current load. |
| Pressure drop and GPM | Manufacturer pressure-drop tables or field instruments can estimate flow. | Use the correct model chart and fluid condition. |
| Loop pressure | Static fill pressure helps identify leaks, air, or service changes later. | Record cold and operating pressure when possible. |
| Fluid and antifreeze | Fluid properties affect pressure loss and freeze protection assumptions. | List type, concentration, and test method. |
| Pump and flow center | Pump model, speed, wiring, and settings affect delivered flow. | Record the exact setting used during readings. |
Decision Logic
- Confirm the record names the exact equipment and operating mode.
- Check whether the fluid type and antifreeze concentration are listed.
- Read EWT and LWT together with pressure drop and GPM, not as isolated numbers.
- Compare flow to the selected equipment requirement and pump setting.
- Confirm loop pressure, purge status, strainers, valves, and service access were checked.
- Use the record as a future baseline, not as a promise that every future reading will match.
Worked Example
Example only: a startup sheet lists cooling mode, 72 degrees F return air, 90 degrees F EWT, 100 degrees F LWT, and a pressure drop across the heat exchanger. That temperature split cannot be judged fairly unless the record also shows GPM, pump setting, loop pressure, antifreeze, and the manufacturer chart used for that model.
You cannot record a baseline you cannot reach, so I walk the mechanical room checklist before startup day: clearance, condensate, electrical, and access to the flow center.
Field Checklist
- Model, serial, loop type, and equipment mode are recorded.
- Air-side or load-side readings match the mode being tested.
- EWT, LWT, loop pressure, and pressure drop are recorded after operation stabilizes.
- GPM method is noted: pressure-drop chart, flow meter, or other approved method.
- Fluid type, antifreeze concentration, and freeze-protection assumption are written down.
- Flow center model, pump speed or setting, valves, strainers, purge status, and filter condition are documented.
- Startup alarms, lockouts, or deviations from manufacturer literature are noted.
Safety And Professional Boundary
Commissioning involves live electrical equipment, moving pumps, pressurized fluid, antifreeze, and manufacturer-specific procedures. Homeowners can keep and read the record, but field measurement and correction should be handled by qualified technicians.
When To Call Hartzell’s
I am IGSHPA accredited and a ClimateMaster GeoElite dealer. Factory training is where a commissioning record stops being paperwork: the startup values that belong on it come from the model-specific manual, and being a dealer is how I get support on that model when a reading does not agree with the book.
Call Hartzell’s when a geothermal system has no startup record, the record is missing flow or fluid data, or current readings no longer match the commissioning baseline.
Related geothermal pages
Primary sources used
These sources set the technical context. The page does not replace the model-specific manual, local code, or field measurements for a real job.
- ClimateMaster Tranquility 30 Digital TE installation manual – Model-specific startup, P/T port flow checks, water-side pressure drop, fluid, antifreeze, and servicing boundary examples.
- PPI TN-55 plastic piping materials for ground source geothermal – Loop fluid, antifreeze, pressure loss, static water pressure, and piping/material compatibility boundaries.
- PPI HDPE geothermal piping – HDPE ground heat exchanger material and joining context.
- IGSHPA standards page – Current CSA/ANSI/IGSHPA C448:2025 standard boundary for ground-source heat pump design and installation.
- IGSHPA manuals page – Manual topics for residential/light-commercial design, soil and rock classification, flushing, purging, and installation practice.
- ENERGY STAR geothermal heat pump key product criteria – Water-to-air, water-to-water, and direct geoexchange product category definitions plus COP/EER rating context.
FAQ
Is a commissioning record the same as a service diagnostic?
No. Commissioning records document the installed system at startup. Diagnostics compare current readings against expected conditions later.
What readings should be on the record?
At minimum, the record should identify equipment, loop type, fluid, antifreeze, loop pressure, EWT, LWT, pressure drop, calculated or measured GPM, pump settings, and operating mode.
Can one startup record prove long-term performance?
No. It gives a baseline. Future readings still depend on load, weather, loop temperature, maintenance, and system condition.