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Diagnostic training workbench

Manifold.

When fault finding a refrigeration system, always start with pressure to get your bearings.

A practical learning reference for connecting pressure readings with ammonia saturation temperature and the refrigeration equipment around them.

Open pressure panel ↓Build system flow ↓

01 / Pressure panel

Move the gauges.

When fault finding a refrigeration system, always start with pressure to get your bearings.

Move each gauge, compare saturation with the relevant set point or ambient condition, then use the learning flag to decide what needs to be verified.

Gauge arrangementTwo stageManual selection while no MT or LT vessel is active.
Low-side reference

Suction

LP
-100100300500700900R717kPa(g)
250 kPa(g)

R717 saturation -5.1 °C

kPa(g)
Pressure may be too high

The LP saturation temperature is -5.1 °C, which is not below the -20.0 °C set point. Confirm load, airflow and the actual control condition.

Interstage reference

Intermediate

IP
02004006008001000120014001600R717kPa(g)
500 kPa(g)

R717 saturation 9.6 °C

kPa(g)
Too high to achieve the set point

IP saturation is 9.6 °C. It cannot provide refrigeration to a 1.0 °C chiller set point without a lower evaporating condition.

High-side reference

Discharge

HP
020040060080010001200140016001800200022002400R717kPa(g)
1,000 kPa(g)

R717 saturation 28.3 °C

kPa(g)
No apparent heat-rejection approach

HP saturation is 28.3 °C against 30.0 °C ambient. Confirm the reading and the correct wet-bulb and water conditions reference.

02 / System builder

Trace the refrigerant path.

Configure a simplified industrial ammonia system and watch the block-flow schematic redraw around your selection.

Change vessel levels and manifold pressures to see the schematic respond. Red equipment requires diagnostic review. Yellow equipment indicates a developing condition.

Selected systemOne compressor branch · Direct expansion · Evaporative condenser · HP receiver
R717
Interactive ammonia refrigeration system flowCompressor branches are on the right, the condenser is at the top, the high-pressure receiver is on the left and expansion is at the bottom left. Medium-temperature and low-temperature vessels each feed their own evaporator bank.NH₃ COACH / LIVE DIAGNOSTIC FLOW / NOT FOR CONSTRUCTIONPRESSURES AND LEVELS LINKEDCD-101CondenserEvaporativeHP receiver, 30% level. Level within training range.V-10130%HP receiverLEVEL NORMALHigh-pressure liquidXV-101ExpansioncontrolHP pressure reductionEV-101Evaporator bank2 × evaporatorsCHECKC-101Compressor 1Screw packageDISCHARGE HEADERLIQUID FEEDSUCTION HEADERDISCHARGE / HOT GASLIQUID FEEDSUCTION / WET RETURNDIAGNOSTIC WARNING

Simplified training schematic only. It does not show every valve, control, relief, isolation, instrument or safety function required on a site P&ID.

Calculation basis

Pressure made legible.

The saturation readout converts the selected gauge pressure to absolute pressure, then applies published ammonia vapour-pressure correlations. Results are rounded for training display and should not be treated as certified property data.

View the NIST ammonia data source ↗
Operational boundary

Manifold is a simplified educational tool. Always use the current site P&ID, approved procedures, calibrated instruments, verified refrigerant property data and competent engineering or technical supervision for real plant work.