TL;DR

Short cycling compressors wear out quickly. Check thermostat location for false load signals and verify the compressor minimum off-time delay is active in the controls.

What you might see

compressor cycles on and off every few minutes
temperature swings above and below setpoint repeatedly
high compressor start count in the unit log
space never reaches setpoint temperature

Likely causes

Tap to mark as ruled out

Thermostat or sensor positioned in a cold supply air stream or near a door, causing false load signals
Equipment oversized for the actual heat load, satisfying demand too quickly before the space is dehumidified
Low refrigerant charge causing rapid pressure drop and low-pressure cutout cycling
Compressor minimum off-time anti-short-cycle relay bypassed or failed

Required tools

Manifold gauge set
Trane Voyager controller access (cycle log)
Thermocouple or digital thermometer
Time delay relay (if external addition is needed)
LOTO kit

Safety first

Lock out the unit before accessing internal controls or refrigerant service ports.
EPA Section 608 certification is required before connecting gauges to the refrigerant system.

Procedure

6 steps · ~30 min

1
Review the unit controller log for the compressor cycle count and on-time. Cycles shorter than 4 minutes are destructive to compressor lubrication.[1]
2
Verify the thermostat or BAS setpoint sensor is not in a cold draft or near an exterior door. Relocate the sensor if needed.
3
Check the refrigerant charge. Low charge causes rapid low-pressure cutout trips. Measure suction pressure and superheat.[1]
4
Confirm the anti-short-cycle time delay is enabled in the unit controls. The Trane Voyager has a built-in delay of typically 4-5 minutes. Verify it is not bypassed.
5
If the unit is oversized, add external time delay relay in the compressor start circuit to enforce a minimum run time of 6 minutes.
6
Check the low-pressure cutout switch setting. If the cutout is set too high relative to the current refrigerant charge, adjust or replace the switch to Trane specification.

Sources

Trane Voyager Commercial Rooftop Service Literature, Trane (Trane Technologies)
Trane Voyager Commercial Rooftop IOM, compressor protection and anti-short-cycle procedures (general)
View source

More guides for Trane Voyager

How to fix bad odor from vents on a Trane Voyager HVAC unit

Musty odor from vents is microbial growth on the evaporator coil or in the drain pan. Clean and disinfect the coil and pan. Install a UV-C lamp to prevent recurrence.

~45 min7 steps

How to fix a frozen evaporator coil on a Trane Voyager HVAC unit

A frozen coil means either blocked airflow or low refrigerant charge. Run the fan-only defrost cycle first, then address the root cause before restarting cooling.

~60 min7 steps

How to fix high energy consumption on a Trane Voyager due to dirty coils

Dirty condenser coils raise head pressure and increase compressor work. A 10% reduction in condenser airflow adds roughly 5% to energy consumption. Clean coils at least annually.