Chiller repair is the work of finding out why a chiller has lost capacity, tripped, leaked or stopped, correcting that cause, and returning the machine to stable service; Paul Industries repairs, overhauls and replaces air-cooled, water-cooled, glycol and process water chillers nationwide, together with the pumps, heat exchangers and piping connected to them. This page is for the plant engineer, facility manager or maintenance lead with a misbehaving chiller, an aging machine that needs a decision, or a replacement to plan. For selecting and sizing a new process machine, see our process chillers page and the industrial process chillers guide.
What chiller repair services cover
Chiller repair services cover every part of the machine that moves heat, plus the water or glycol loop that brings heat to it, because a fault in either one shows up at the chiller control panel. In brief, refrigerant boils in the evaporator as it absorbs heat from the chilled water, the compressor raises its pressure, the condenser rejects the heat, and an expansion device drops the pressure again; a fault anywhere in that loop, or in the water through either heat exchanger, costs capacity or trips a safety.
The same diagnostic logic applies to commercial chiller repair on a comfort plant and to a process machine holding a reactor jacket or mold at temperature. What changes is the cost of downtime: an hvac chiller repair can often wait for a mild day, while a process chiller holding product quality usually cannot.
| Area | Typical faults | Repair work |
|---|---|---|
| Compressor | Worn bearings, failed motor windings, oil loss, valve or rotor damage, slide valve or vane problems | Diagnosis by oil analysis, vibration and winding resistance; component repair, rebuild or compressor replacement with circuit cleanup |
| Refrigerant circuit | Leaks, moisture, acid, non-condensables, restricted filter-driers, failed expansion valves | Leak location and repair, evacuation, drier and valve replacement, charge by weight to the nameplate |
| Evaporator | Fouled tubes or plates, low flow, freeze damage, tube leaks | Flow correction, cleaning, tube testing, leak repair, freeze-protection review |
| Condenser | Scaled tubes, dirty or damaged coils, failed fans, warm or low condenser water | Tube or coil cleaning, fan and motor repair, condenser water flow and tower checks |
| Pumps and loop | Worn seals, failed bearings, clogged strainers, air in the loop, wrong glycol mix | Pump repair or replacement, strainer cleaning, air removal, fluid testing and correction |
| Controls and sensors | Drifted temperature or pressure sensors, failed flow switches, bad setpoints | Calibration, sensor and switch replacement, setpoint and staging review |
| Piping and valves | Leaking joints, passing isolation valves, corroded sections, vibration damage | Joint and valve repair, section replacement, supports and isolators, pressure testing |
Common chiller problems and what they usually point to
Most chiller faults fall into a handful of symptoms, and each symptom narrows the search to a few likely causes before any panel is opened. The readings that separate those causes are entering and leaving water temperatures on both heat exchangers, water flow, refrigerant pressures converted to saturation temperatures, superheat, subcooling, compressor amps and oil pressure. Compared against the startup log, they usually tell the story.
Chiller not cooling or not holding setpoint
A chiller not cooling to setpoint is either short of capacity or being asked to carry more than it was selected for, and the first readings decide which. Flow follows a simple relation: gallons per minute equal 24 times tons divided by the temperature difference in degrees Fahrenheit, so a machine selected for a 10 degree difference needs about 2.4 gallons per minute per ton. If flow and temperature difference show a load above design, the fix is in the process, not the machine. If the load is normal and leaving water still runs warm, the usual causes are a fouled heat exchanger, low refrigerant charge, a failed compressor stage, a stuck capacity control or a sensor reading wrong.
High head pressure
High condensing pressure means the condenser cannot reject heat fast enough, and the causes are almost always on the heat rejection side. On air-cooled units, look first at dirty or blocked coils, failed fans and hot discharge air recirculating into the intake. On water-cooled machines, scaled tubes, low condenser water flow and a cooling tower returning water too warm are the usual suspects. Non-condensable gas in the circuit and an overcharge also raise head pressure.
Low suction pressure and freeze trips
Low evaporator pressure points to too little heat reaching the refrigerant or too little refrigerant reaching the evaporator. Low chilled water or glycol flow from a clogged strainer, a closed valve or a weak pump starves the evaporator of heat, while a low charge, a restricted drier or a failing expansion valve starves it of refrigerant. Either one can drive the refrigerant toward freezing and trip the low-pressure or freeze-protection safety. An air-cooled unit in cold weather without head pressure control can also pull suction pressure down.
Tripping on safeties, leaks and a noisy compressor
A machine that trips repeatedly is reporting a real condition, so resetting it without finding the cause usually ends in a larger failure. Flow-switch trips trace to the pumps and loop, overload and phase faults to the power supply or motor, and oil pressure trips to oil loss or refrigerant diluting the oil. Oil stains on fittings and a falling charge mark leaks. A compressor that knocks or grinds may be taking liquid back or losing bearing clearance, and should be stopped and diagnosed rather than run to failure.
| Symptom | First readings to take | What the readings usually mean |
|---|---|---|
| Warm leaving water | Water temperatures in and out, flow, compressor loading | Load above design if flow and temperature difference are high; lost capacity if the load is normal |
| High head pressure | Condensing saturation temperature vs leaving condenser water or ambient air | A wide gap points to fouling or non-condensables; a normal gap with warm water points to the tower or ambient |
| Low suction pressure | Evaporating saturation temperature, superheat, evaporator flow | High superheat suggests low charge or a restriction; normal superheat with low flow points to the loop |
| Rising evaporator approach | Leaving water temperature minus evaporating temperature, trended over months | Fouling on the water side, oil logging on the refrigerant side, or a low charge |
| Compressor noise or high amps | Oil pressure and level, discharge temperature, superheat, vibration | Low superheat suggests floodback; low oil points to oil loss; rising vibration to bearing wear |
| Frequent purge operation on a low-pressure machine | Purge run time and pump-out counts | Air leaking into the evaporator side, which also brings moisture into the refrigerant |
How a chiller repair visit runs, from triage to return to service
A well-run repair visit moves in a fixed order: make the situation safe, collect the evidence, find the root cause, repair it, prove the repair and record what was done.
| Step | What happens | What you get |
|---|---|---|
| 1. Intake | Alarm history, symptoms, load at the time of failure, recent work and the last good readings are gathered before arrival | A short list of likely causes and the right parts and tools on the truck |
| 2. Make safe | Lockout and tagout, isolation of the machine and loop, refrigerant area check under the site’s safety rules | A safe machine and a clear understanding of what the process is losing |
| 3. Readings | Pressures, temperatures, flows, amps, oil condition and vibration taken under load if the machine will run | Data compared against design, startup and trend values |
| 4. Root cause | The readings are matched to a cause and confirmed by test, such as leak detection, winding resistance or an oil sample | A cause, not just a failed part |
| 5. Repair plan | Options with time, cost drivers and risk, including temporary cooling if the repair is long | A decision you can make with the facts in front of you |
| 6. Repair | Refrigerant recovered as the regulations require, parts replaced, circuit cleaned and dried where needed | A repaired machine |
| 7. Prove it | Pressure and leak test, evacuation, charge by weight, restart and run under load while readings settle | Stable leaving water temperature and normal operating values |
| 8. Report | Readings before and after, cause, parts, refrigerant added or recovered and recommendations | A record for your maintenance system and any leak-rate calculation |
Chiller compressor repair vs replacement
Chiller compressor repair makes sense when the damage is limited to replaceable components and the rest of the machine is sound; replacing the compressor makes sense when the motor has burned out, the rotating parts are badly damaged or rebuild time is longer than the process can tolerate. Large semi-hermetic and open screw and centrifugal compressors are built to be serviced; small hermetic scroll and reciprocating compressors are replaced whole. Lead time matters as much as price: an exchange compressor on the shelf can restore production days before a rebuild.
How to repair chiller compressor faults without a repeat failure
The compressor is usually the victim, not the cause, so every compressor job includes finding out what killed it. Liquid floodback, oil loss, short cycling, repeated low-flow events and power quality problems all destroy compressors, and will destroy the replacement too if left in place.
When a motor burns out, it leaves acid and carbon in the refrigerant and oil. The cleanup follows a known sequence: test the oil for acid, install a suction-line filter-drier with acid-removal cores ahead of the new compressor and an oversized liquid-line drier, watch the pressure drop across the suction drier during the first hours of operation, and change cores and oil until the acid test stays clean. A laboratory oil sample confirms the circuit is clean; skipping this is a reliable way to lose a second compressor within months.
Chiller leak repair and why leaks come back
Chiller leak repair means locating every leak, fixing it permanently and proving the circuit tight, because adding refrigerant to a leaking machine only resets the clock. Leaks recur for physical reasons: vibration fatigues small tubing and brazed joints, fittings loosen with temperature cycling, seals and valve packing wear, relief valves weep after lifting, and corrosion pits tubes from the water side.
Low-pressure centrifugal machines using refrigerants such as R-123, R-1233zd(E) or R-514A run the evaporator below atmospheric pressure, so a leak pulls air and moisture in rather than letting refrigerant out. The purge unit removes that air, and its run time is the leak indicator to watch. On positive-pressure machines, a tube leak in the evaporator or condenser lets refrigerant into the water; on low-pressure machines, a tube leak lets water into the refrigerant, which is far more damaging and needs immediate shutdown, drying and oil change.
Leak repair is also a regulatory obligation. Under the EPA Emissions Reduction and Reclamation rule issued under the AIM Act, from January 1, 2026 appliances holding 15 pounds or more of an HFC or substitute refrigerant with a global warming potential above 53 must have leaks repaired when the annualized leak rate exceeds 10 percent for comfort cooling, 20 percent for commercial refrigeration or 30 percent for industrial process refrigeration. Repairs are due within 30 days of adding refrigerant, or 120 days where an industrial process shutdown is needed, and verification tests are required. Machines on ozone-depleting refrigerants have long had parallel obligations under Clean Air Act Section 608.
Air-cooled vs water-cooled chiller repair
Air cooled chiller repair centers on the outdoor condenser coils, fans and the effects of weather, while water cooled chiller repair centers on condenser tubes, condenser water flow and the cooling tower that serves them.
| Repair area | Air-cooled chillers | Water-cooled chillers |
|---|---|---|
| Heat rejection fouling | Dust, cottonwood, grease and debris in finned or microchannel coils | Scale, biofilm and debris in condenser tubes from tower water |
| Cleaning method | Low-pressure rinse and coil cleaner suited to the coil type; microchannel coils need gentle handling | Mechanical tube brushing, with chemical descaling where scale is heavy |
| Moving parts outside the machine | Condenser fans, motors, belts on some units, fan speed controls | Condenser water pumps, tower fans, tower valves and strainers |
| Weather effects | Capacity falls in hot weather; cold weather needs head pressure control; hail bends fins | Tower performance falls on humid days; freeze protection for outdoor tower piping |
| Inspection beyond the machine | Airflow clearances and hot air recirculation around the unit | Tower fill, drift eliminators, basin and water treatment results |
| Tube condition | Evaporator only | Evaporator and condenser, with periodic eddy current testing of tube walls |
Tower water chemistry decides how fast condenser tubes foul, so tube cleaning without a look at the tower only buys time; our cooling tower water treatment page covers that side. Ratings under AHRI 550/590 assume a clean-machine fouling allowance of 0.00025 hour square foot degree Fahrenheit per Btu on the condenser and 0.0001 on the evaporator, so an approach drifting well past its startup value means fouling beyond the rating and extra compressor power.
Glycol chiller repair
Glycol chiller repair starts with the fluid, because the wrong concentration, depleted inhibitors or a loop full of air causes a large share of the trouble on low-temperature machines. Published data for propylene glycol show a freeze point of about 8 degrees Fahrenheit near 30 percent by volume, about minus 7 near 40 percent and about minus 28 near 50 percent, and the fluid supplier’s guidance is to pick a freeze point at least 5 degrees Fahrenheit below the lowest temperature the loop will see.
Too little glycol risks a frozen evaporator, which can split tubes or plates and mix fluid with refrigerant. Too much costs capacity, because glycol carries less heat than water and thickens as it cools. Concentration is checked with a refractometer, inhibitors and pH with a fluid test, and makeup is premixed to the target rather than topped off with plain water. On the glycol side, worn pump seals, clogged strainers and a fouled heat exchanger between the chiller and the process loop are common capacity thieves. Our glycol cooling systems page covers how these loops are designed and built.
Process water machines that serve molds, presses, lasers and jacketed vessels see similar problems on the water side. An industrial water chiller repair often turns out to involve the pump package, reservoir, a passing bypass valve or a clogged process strainer as much as the refrigeration circuit. A small water chiller repair on a single machine follows the same triage as a plant-room job, only faster.
Chiller repair vs replacement: the decision factors
The repair or replace decision comes down to whether the money spent on the current machine buys enough reliable years at an acceptable energy cost, compared with what a new machine and its installation would cost over the same period. Age alone does not decide it.
| Factor | Points toward repair | Points toward replacement |
|---|---|---|
| Age and condition | Well within its expected life, tubes and shell sound, good maintenance records | Near or past typical service life with several major components worn |
| Size of the failure | Repair cost a modest share of a new installed machine | Repair cost a large share of replacement on an old machine |
| Refrigerant | Current refrigerant with stable supply | R-22, whose production and import ended January 1, 2020, or HCFC-123, whose servicing supply ends in 2030 |
| Efficiency | Efficiency close to original after cleaning and tuning | Energy savings from a new machine repay a large share of its cost within a few years |
| Parts and controls | Parts and controls still supported | Obsolete controls, long lead times or discontinued parts |
| Load fit | Capacity and temperature still match the load | Load has grown, shrunk or changed temperature so the machine runs badly |
| Downtime risk | Redundant capacity covers outages | A single machine on a critical load with a rising failure rate |
Refrigerant deserves a careful look. Existing R-22 equipment can legally keep running on recovered and reclaimed refrigerant, but supply costs rise as stock shrinks, so a major failure on a phased-out refrigerant is usually the strongest case for replacement.
How long does a chiller last?
A chiller typically lasts about two decades: the ASHRAE median service life table lists 20 for reciprocating machines and 23 for centrifugal and absorption machines, and newer ASHRAE data suggest many centrifugal machines run past 25 with good care. Half of machines outlast a median; water treatment, run hours, starts and how quickly leaks were fixed move any one machine’s life up or down.
How often do chillers need to be replaced?
Chillers are replaced when the decision factors above line up, not on a fixed calendar. Budgeting around the 20-year mark and confirming with a condition assessment a few years ahead keeps a failure from forcing the decision.
Chiller overhaul: scope and intervals
A chiller overhaul is a planned teardown, inspection and rebuild of the compressor and a full check of the rest of the machine, done before wear turns into failure. Manufacturers publish overhaul intervals mostly in running hours: one manufacturer’s service guidance, for example, recommends an overhaul every 40,000 running hours on centrifugal machines and a minor overhaul at 20,000 hours with a major one at 40,000 on screw machines. A machine running all year logs 8,760 hours, so 40,000 hours comes around in about four and a half years of continuous duty, and much later on a seasonal comfort machine. Oil and vibration trends can move it either way.
A typical overhaul covers compressor teardown with bearings, seals and clearance checks, the oil system, motor winding tests, valves and driers, eddy current tube testing, sensor calibration and a controls review. Overhauls fit best in a low-load season or a planned outage, as covered on our shutdown and turnaround services page.
Chiller replacement scope of work
A complete chiller replacement scope of work covers everything from the site survey to the handover documents, so that nothing between the old machine’s last day and the new machine’s first full load is left undefined.
| Phase | Work included |
|---|---|
| Survey and selection | Measured load and temperatures, existing piping and pad, access route, power and controls connections, selection support for the new machine |
| Temporary cooling | Rental or spare capacity, connection points, duration and who runs it |
| Removal | Refrigerant recovery, draining and disposal of oil and fluid, disconnection, disassembly where access requires it |
| Rigging and setting | Crane or skate plan, removal and set of the new machine, leveling, vibration isolation |
| Piping tie-in | New flanges, valves, strainers, gauges, flow meters and transitions to the existing headers |
| Flushing and testing | Loop flushing before the new evaporator sees water, pressure testing of new piping to the governing code |
| Startup and commissioning support | Manufacturer startup, functional testing under load, controls integration, readings logged as the new baseline |
| Handover | As-built drawings, test records, startup report, operating and maintenance information, training |
Rigging is often the hardest part of an industrial chiller replacement: an old plant-room machine may have to come out in pieces through a door the new one barely fits, and a rooftop unit may need a crane and a road closure. Our millwright and rigging crews handle that work. New piping is shop fabricated where possible through our pipe fabrication shop so the tie-in window stays short, and new joints are tested under our hydrostatic testing procedures to ASME B31.9 for building services piping or ASME B31.3 for process piping. A commercial chiller replacement on a rooftop follows the same phases as a plant-room process job, differing mostly in access and temporary cooling.
What drives chiller replacement cost
Chiller replacement cost is driven as much by the work around the machine as by the machine itself, so two jobs with the same chiller can cost very different amounts. The main factors are:
- Capacity, compressor type and efficiency level of the new machine, and whether it is air-cooled or water-cooled.
- Access: crane size, building openings, disassembly of the old unit and any structural work for a heavier machine.
- Piping changes where the new connections do not line up, plus new valves, strainers and instruments.
- Power and controls connections, and integration into the plant control system.
- Temporary cooling: size, duration and fuel or power for the rental equipment.
- Flushing, testing, startup and documentation, which grow in regulated plants.
How long does it take to replace a chiller?
Replacing a chiller usually takes longer to plan and procure than to install: the on-site changeout of a like-for-like packaged unit is often measured in days to a couple of weeks, while selection, approvals and manufacturing lead time for a large machine are often counted in months. Disassembly, major piping changes and short outage windows lengthen the site work. Ordering early, prefabricating piping and connecting temporary cooling before the old machine stops shorten the outage most.
Chiller repair and maintenance programs
A chiller repair and maintenance program combines scheduled inspection with priority response, so faults are caught as trends instead of trips. ANSI/ASHRAE/ACCA Standard 180, which sets minimum inspection and maintenance practice for commercial building HVAC systems, is a useful baseline; process duty usually calls for tighter intervals.
| Interval | Typical tasks |
|---|---|
| Every shift or day | Log water temperatures, pressures, amps, oil level and alarms; on low-pressure machines note purge run time |
| Monthly | Review logs for drifting approach temperatures, check strainers, leak check at known weak points, inspect air-cooled coils |
| Quarterly | Glycol concentration and inhibitor test, condenser water treatment review, pump and motor checks, sensor spot checks |
| Annually | Oil analysis, condenser tube cleaning or coil cleaning, refrigerant leak test, motor winding test, safety and control calibration |
| Every few years or by run hours | Eddy current tube testing, compressor inspection or overhaul at the manufacturer’s interval, valve and relief device replacement |
Our chiller maintenance services can be part of a broader plant program under our preventive maintenance work, and a written agreement under our service contracts sets the scope. A good maintenance services agreement names the machines, tasks and intervals, who supplies consumables, breakdown response times, reporting, and how repairs found on inspection are approved. Chillers can also join our wider industrial maintenance services.
Emergency chiller repair: keeping the load cool
Emergency chiller repair starts with protecting the load, not just fixing the machine: the first decisions are how much cooling the process can lose, for how long, and what temporary capacity can be connected. Plants with pre-installed, valved and capped tees on the headers sized for a rental unit recover hours faster than plants that cut them in during the outage.
Machine type and capacity, alarm codes, what changed before the failure and current water temperatures speed the response. Our emergency repair service page covers 24-hour response across process and utility systems. In data centers, where the chiller plant is designed around redundancy, our data center chillers page covers how failover and repair fit together.
Who services chillers, and how to choose a chiller repair contractor
Chillers are serviced by mechanical contractors with refrigeration technicians who can diagnose the machine, recover and handle refrigerant under the EPA rules, and repair the compressor, heat exchangers, controls and the loop around them. Paul Industries services chillers as part of the whole cooling system, since many faults start in the pumps, piping, glycol or heat rejection equipment.
When choosing a contractor, ask how they diagnose before replacing parts, what readings they leave behind, whether they cover air-cooled, water-cooled, glycol and process water machines, how they keep refrigerant records, what their emergency response looks like, and whether they can carry a job from repair through full replacement. Ask how they build a chiller repair cost estimate too: one that explains the diagnosis and options first is easier to plan around. Because a chiller sits inside larger chilled water systems, a contractor who works on the whole loop can follow a fault wherever it leads.
What Paul Industries does on chillers
Paul Industries diagnoses and repairs air-cooled, water-cooled, glycol and process water chillers; repairs compressors, refrigerant leaks, condensers, evaporators, pumps, controls and the chilled water, condenser water and glycol piping around them; performs overhauls; plans and carries out replacements from survey and selection through rigging and setting, piping tie-in, flushing, pressure testing, startup and commissioning support; and provides scheduled maintenance and emergency repair for process plants and commercial facilities nationwide. Request a quote for a chiller repair, an overhaul or a replacement plan.
Standards referenced: EPA Clean Air Act Section 608 · EPA AIM Act Emissions Reduction and Reclamation Rule · ASHRAE Standard 15 · ASHRAE Standard 34 · ANSI/ASHRAE/ACCA Standard 180 · AHRI 550/590 · ASME B31.9 · ASME B31.3
Frequently asked questions
What drives chiller repair cost?
The diagnosis time, the part that failed and its lead time, whether refrigerant must be recovered and replaced, how much access work the repair needs, and whether the work happens during normal hours or an outage. A failed sensor or contactor is a small job; a compressor replacement with burnout cleanup or a tube leak with dehydration is a large one. Getting a cause before a quote keeps the number honest.
Can a chiller compressor be rebuilt instead of replaced?
Large semi-hermetic and open screw and centrifugal compressors are designed to be rebuilt with new bearings, seals and wear parts, and a rebuild can return them to like-new condition. Sealed hermetic scroll and small reciprocating compressors are replaced whole. The choice also depends on rebuild time versus the availability of an exchange unit.
Why does my chiller keep tripping on high pressure?
Repeated high-pressure trips mean the condenser is not rejecting heat fast enough. On air-cooled units check for dirty coils, failed fans and recirculating hot air; on water-cooled units check for scaled tubes, low condenser water flow and warm tower water. Non-condensable gas in the circuit and overcharging are the other common causes.
What does a low suction pressure alarm on a chiller mean?
It means the evaporator is either not getting enough heat from the water or not getting enough refrigerant. Low chilled water flow, a low charge, a restricted filter-drier and a failing expansion valve are the usual causes. Superheat readings help separate a refrigerant-side problem from a water-side one.
Is it worth repairing a chiller that uses R-22?
It can be, for a minor repair on a machine in good condition, because existing R-22 systems may keep running on recovered and reclaimed refrigerant. For a major failure, a large leak or a machine near the end of its service life, the rising cost of R-22 usually tips the decision toward replacement with a machine on a current refrigerant.
How do you find a refrigerant leak on a chiller?
Technicians use electronic detectors, bubble solution on suspect joints, ultraviolet dye on some systems and standing pressure tests with nitrogen when the circuit is open. On low-pressure machines, rising purge run time signals an air leak, and the machine may be pressurized slightly for leak testing. Water in the refrigerant or refrigerant in the water points to a tube leak.
What is a chiller purge unit?
It is a small device on low-pressure centrifugal chillers that removes air and moisture which leak into the evaporator side because it operates below atmospheric pressure. Non-condensables raise head pressure and moisture forms acid, so the purge keeps the refrigerant clean. A purge that runs more and more is a sign of a growing leak.
How is temporary cooling provided during a chiller outage?
A rental chiller is set nearby and connected to the loop through hoses or pipe at valved connections on the supply and return headers, with temporary power and, for water-cooled rentals, a temporary heat rejection path. Sizing it to the actual load rather than the nameplate keeps the rental smaller. Permanent tie-in points installed in advance make the connection a short job.
What should a chiller service report include?
Readings before and after the work, the root cause found, parts replaced, refrigerant recovered and added by weight, test results, and recommendations with priorities. Refrigerant records are needed for the annual leak-rate calculation under the EPA rules, and before-and-after readings become the baseline for spotting the next problem early.
Can water get into the refrigerant circuit of a chiller?
Yes, through a leaking tube in the evaporator or condenser. On low-pressure machines water is drawn into the refrigerant side; on positive-pressure machines refrigerant usually escapes into the water instead. Water in the circuit makes acid and damages the compressor, so the machine is shut down, the leak located, the circuit dried and the oil changed.
What glycol concentration does a glycol chiller need?
Enough to put the freeze point at least 5 degrees Fahrenheit below the lowest temperature the loop or any outdoor piping will see, and no more, because extra glycol cuts heat transfer and raises pumping power. The right number comes from the loop's own minimum temperature and the fluid supplier's freeze-point table, confirmed in the field with a refractometer.
Why won't my chiller restart after a power outage?
Most chillers hold off a restart for a set time to protect the compressor, and many need a manual reset after a power loss or phase fault. If it still will not start, check for flow-switch faults from pumps that did not restart, low oil temperature after a long outage, and tripped safeties logged on the panel.
How long does a compressor replacement on a chiller take?
For a small hermetic compressor that is in stock, the swap, evacuation and restart can fit within a day or two. Large compressors that must be rigged out, rebuilt or ordered take longer, sometimes weeks, which is when temporary cooling and an exchange compressor become worth pricing.
Does an overhaul extend a chiller's service life?
Yes. Replacing bearings, seals and worn parts before they fail, and finding tube thinning through eddy current testing, lets a sound machine run well beyond the point where neglected units are scrapped. An overhaul does not fix an obsolete refrigerant or a machine that no longer matches its load.
Should a replacement chiller be the same size as the old one?
Not automatically. Loads change over a chiller's life, and original machines were often oversized. Measured load data, future plans and the part-load profile should set the new capacity; a slightly smaller machine or two smaller ones can run more efficiently and give redundancy.
What records help a contractor diagnose a chiller faster?
Daily logs of temperatures and pressures, the startup report, the alarm history, refrigerant added over the past year, oil analysis results and water treatment reports. Trends show what changed and when, which is often the fastest path to the cause.
Do chillers need to be shut down for maintenance?
Logging, leak checks and many inspections are done with the machine running. Tube cleaning, oil changes, eddy current testing and overhauls need it off and isolated, so plants with one machine schedule them in a low-load period, while plants with spare capacity rotate machines out one at a time.
What happens to the old refrigerant when a chiller is replaced?
It is recovered into approved cylinders before the circuit is opened, as the EPA rules require, and then reclaimed or properly disposed of. The recovered quantity is recorded, and the oil and any glycol are drained and handled as waste or recycled.
Related: Process Chiller Installation & Service · Industrial Process Chillers: How They Work & How to Choose · Data Center Chillers · Chilled Water Systems · Emergency Repair & Breakdown Response · Preventive Maintenance & Service Contracts · Request a quote