Troubleshoot Library

Verified troubleshooting guides for industrial equipment

Step-by-step procedures for alarm codes, fault diagnoses, and routine fixes, cross-checked against OEM operator manuals, maintained by Dovient's reliability team.

41 categories157 machines573 guides

This library is what a senior maintenance tech would hand a newer one on a bad day. Real alarm codes on real machines, with the checks that catch the mistake before you waste an hour on the wrong hypothesis. Every procedure is cross-checked against the OEM operator manual for that model. Citations are at the bottom of each page, not in a footer nobody reads.

Browse by industry

Start here if you know the plant you work in. Each industry hub lists the machine families we have troubleshooting guides for across that vertical.

Oil refinery and plant tower column refinery of petrochemistry industry in oil and gas industry with cloud blue sky cloud the twilight background

Oil & Gas

Upstream and midstream production gear, wellhead controllers, separators, compressors, pumps, and the safety systems oil and gas operators rely on.

7 machines · 21 guides
Pharma industry concept production of medicines and drugs high quality illustration

Pharma & Chemical Process

Pharmaceutical, fine chemical, and continuous-process equipment, autoclaves, reactors, centrifuges, lyophilizers, and the supporting utilities that keep cGMP plants running.

10 machines · 30 guides
Conveyor belt with bottles for juice or water at a modern beverage plant

Food & Beverage

Production equipment for dairy, bakery, brewing, beverage filling, and food processing, fillers, pasteurizers, retorts, freezers, and packaging lines.

7 machines · 21 guides
One working day of modern automatic bus manufacturing with unfinished cars automotive parts workers in protective uniform

Automotive & Auto Parts

Automotive assembly and parts manufacturing equipment, body welding cells, paint booths, transfer presses, and engine plant gear.

5 machines · 15 guides
F35 Lightning II Fighter Jet in a Hangar

Aerospace & Defense

Aerospace and defense manufacturing equipment, 5-axis machining centers, autoclaves, composite layup, NDT systems, and precision grinding.

6 machines · 18 guides
Precision Automation Technology in Action on a HighTech Manufacturing Assembly Line Floor

Semiconductor & Electronics

Wafer fab and electronics assembly equipment, lithography tools, etchers, CVD/PVD chambers, vacuum systems, SMT lines, and reflow ovens.

6 machines · 18 guides
Oxygen supply in hospital surgery ward Air medical system devices

Medical Device

Medical device manufacturing equipment, cleanroom assembly, sterilizers, micro-molders, and laser welders for medical-grade production.

5 machines · 15 guides
Interior of Industrial Steel Warehouse

Metal Fabrication & Sheet Metal

Sheet metal and fabrication equipment, laser cutters, press brakes, turret punches, plasma cutters, and shears used in job shops and OEM fab departments.

6 machines · 18 guides
Colorfull glass beads batches in plastic bags for beadwork in craft shop

Plastics, Rubber & Polymer

Plastic and rubber processing equipment beyond injection molding, extruders, blow molders, thermoformers, and compounding lines.

6 machines · 18 guides
A detailed shot of a mineral processing plant with machinery pipelines and stockpiles of processed materials photo no bw ar 1028689 stylize 250 Job ID e34aa0239a534c9893b34744e38260db

Mining & Minerals

Hard-rock and mineral processing equipment, grinding mills, crushers, screens, conveyors, and the heavy-duty gear that defines mining throughput.

6 machines · 18 guides
Limestone or crushed stone factory in wooded valley

Cement, Lime & Aggregates

Cement and aggregate production equipment, kilns, raw mills, finish mills, preheaters, and material handling systems.

6 machines · 18 guides
Intense Activity in Industrial Metal Foundry

Steel, Metals & Foundry

Steel and foundry equipment, electric arc furnaces, ladle refining, continuous casters, rolling mills, and induction furnaces.

6 machines · 18 guides
Process of creating paper in factory pulp and paper industry

Pulp & Paper

Pulp and paper mill equipment, digesters, bleach lines, paper machines, winders, and supercalenders.

6 machines · 18 guides
Dark blue cystal pattern glasses on the table prepared for luxury dinner event

Glass & Ceramics

Glass and ceramic production equipment, melting furnaces, IS forming machines, lehrs, and tile presses.

6 machines · 18 guides
Blanks for wooden furniture at the factory. Joiner's shop. Wooden blanks for furniture. Industrial production of furniture. Furniture workshop.

Wood, Lumber & Furniture

Sawmill, lumber processing, and furniture-making equipment, saws, planers, sanders, edgebanders, and wood CNC routers.

6 machines · 18 guides
Industrial Building At Night

Power Generation

Utility and industrial power generation gear, gas turbines, steam turbines, generators, switchgear, and balance-of-plant equipment.

6 machines · 18 guides
Industrial water treatment plant featuring heavyduty pumps and pipes for effective water management

Utilities & Water Treatment

Municipal and industrial water treatment equipment, filtration, disinfection, blowers, and the pumps that move drinking and process water.

3 machines · 9 guides
Industrial paper mill transforms wood pulp into paper rolls Large machine processes raw material

Printing, Packaging & Corrugated

Printing and packaging equipment, web offset, flexo, gravure, digital presses, corrugators, die cutters, and folder-gluers.

6 machines · 18 guides
Wood pellets on a conveyor belt in a production facility

Agriculture, Grain & Feed

Grain handling and feed mill equipment, hammer mills, pellet mills, dryers, elevators, and bulk material handling.

6 machines · 18 guides
Textile Manufacturing Process Rolls of Fabric in a Factory

Textiles & Apparel

Textile and apparel production equipment, knitting machines, weaving looms, dyeing, finishing, and nonwovens lines.

5 machines · 15 guides

Browse by equipment class

Start here if you know the machine. Each equipment hub lists every brand and model we cover in that class, across every industry that runs one.

The CNC milling machine cutting the forging mold part by solid radius end mill toolMold manufacturing process

CNC Mills

Vertical and horizontal CNC milling machines: troubleshooting guides, alarm references, and procedures for common makes and models.

3 machines · 12 guides
Electrical switchboard pumping station Control units and electr

VFDs & Drives

Variable frequency drives and servo drives that control motors on industrial machinery, fault codes, parameter errors, and replacement procedures.

1 machine · 7 guides
CloseUp Dolly Shot Of A Metal Conveyor Belt In Motion

Rotating Equipment

Electric motors and rotating machinery that drive every pump, fan, conveyor, and machine tool in a plant. Found in 99% of manufacturing facilities.

1 machine · 7 guides
Industrial water filtration system with stainless steel tanks and gauges Concept of water purification filtration technology clean water industrial engineering

Fluid Handling

Pumps, compressors, and related equipment that move water, chemicals, lubricants, and process fluids through a plant.

2 machines · 15 guides
Production of wooden pallets on a automatic line for woodworking

Material Handling

Conveyors, cranes, hoists, and forklifts, the equipment that moves parts and product through a plant. Found in 85% of manufacturing facilities.

3 machines · 20 guides
Power electronic site

Power Transmission

Hydraulic systems, gearboxes, and speed reducers that transmit motor power to driven loads. The link between source power and the work the machine does.

2 machines · 16 guides
Column high voltage transformer against the field green Electric current redistribution substation

Power Distribution

Electrical panels, transformers, switchgear, and diesel generators, the equipment that delivers and conditions electric power throughout a plant.

4 machines · 26 guides
Industrial Control Panel with Water Drops in Rainy Environment

Power & Control

PLCs and control systems that automate the flow of work in a plant. The brain behind the iron.

1 machine · 6 guides
Engineers use technology to control production machinery in industrial plants.

Process Control

Control valves and final control elements that regulate flow, pressure, and temperature in a process plant.

1 machine · 6 guides
Equipment for the preparation of beer

Process Equipment

Heat exchangers, mixers, agitators, and the workhorse equipment that performs the core processes of chemical, food, and pharmaceutical plants.

2 machines · 10 guides
View of a thermal power plant or a factory for the production and processing of petroleum products Large industrial chimneys against a clear blue sky Removal of combustion

Thermal Processing

Industrial furnaces, ovens, and kilns used for heat treatment, drying, curing, and firing in metals, ceramics, glass, and food production.

1 machine · 6 guides
An industrial building and a chimney with white smoke against a blue sky Air pollution from the smoke of a working factory Chemical industry and the risk of environmental disaster

Steam & Heat

Boilers, steam traps, and heat utility equipment that produce and distribute process steam and hot water.

2 machines · 12 guides
Industrial Manufacturing Environment with Smoke and Conveyor Line

Air Movement

Industrial fans and blowers used for ventilation, combustion air, drying, and process cooling.

1 machine · 6 guides
Industrial Pollution with Smoke Emissions in Urban Landscape

Air Quality

Dust collectors, baghouses, and air filtration equipment that keep plant air clean and meet environmental requirements.

1 machine · 5 guides
Explore efficient data management for industrial IoT factory automation Concept Industrial IoT Factory Automation Efficient Data Management

Automation

Industrial robots and automated work cells that handle assembly, welding, palletizing, and material handling.

1 machine · 6 guides
Workers engaged in metal fabrication at a busy industrial factory during evening hours

Fabrication

Welding equipment and fabrication tools used to join, cut, and form metal in production environments.

1 machine · 6 guides
Asian industrial worker is checking the setup value of metal sheet roll forming machine inside roof factory for safety industry construction concept

Forming

Hydraulic and mechanical presses used to stamp, punch, draw, and form metal parts.

1 machine · 6 guides
Recycling Facility Conveyor Belt with Plastic Bottles and Containers

Plastics Production

Injection molding machines and related plastics processing equipment.

1 machine · 6 guides
a large industrial building with pipeline

Facility Systems

HVAC units, chillers, and cooling towers that maintain comfort, process cooling, and clean rooms in industrial facilities.

3 machines · 20 guides
a room with a fan and a light on the ceiling

Facility & HVAC

Large facility HVAC and building services equipment, central plants, boilers, chillers, and the building automation that ties them together.

2 machines · 6 guides

More categories

How we build these guides

Every published page starts with the OEM operator manual for the machine it covers. A Dovient reliability engineer then compares the manual steps against what actually works on the floor, pulls in published service bulletins where the manual is wrong or outdated, and writes the page with one job in mind: get the tech past the current fault in the fewest safe steps. Nothing on this site is generated and pushed live without a human review. The review pass enforces citation density, safety ordering, and the rule that every step has to be verifiable by a tech standing at the machine.

  • Cited against OEM manuals: Haas, Fanuc, Allen-Bradley, Siemens, Rockwell, ABB, Danfoss, Yaskawa, and others, page and section numbers where possible.
  • Written by people who have actually worked on the equipment, not scraped from forum posts.
  • Every revision is timestamped and reviewable. If the manufacturer issues a bulletin, the page gets updated and the change is logged.
  • Verified badge appears only when the page cites at least one source from the machine's own manufacturer.

Where to start

If you know the machine, go to the equipment class browse and drill into the brand and model. If you are triaging across a whole plant, start with the industry browse. If you are looking at a fault code right now, the fastest path is to search the code inside the relevant machine hub. Every machine page lists its most common faults at the top of the page, ranked by how often techs ask about them.

What these guides will not do

These are field-serviceable procedures for techs and senior operators. They will not replace the OEM service department for major work. Ball-screw replacement, spindle bearing jobs, re-mastering a rotary axis, any crash recovery that might have shifted geometry, torch calibration on a plasma cut center, cavity re-machining on a tool: call the OEM. We mark these cases explicitly at the bottom of the relevant pages. Doing them in-house usually costs more in lost production than the service call would have. Knowing where to stop is part of the job.

Safety is load-bearing

Every procedure on this site assumes the tech has followed lockout-tagout before opening a panel. VFD cabinets and large motor starters store lethal energy in their capacitors for 5 to 15 minutes after power-off. Hydraulic accumulators stay charged. Steam systems hold residual heat. Nitrogen lines on rubber extruders can kill a person in minutes. If a step involves any of these, we call it out before the step, not after.

Popular guides

How to diagnose ammonia injection malfunction on a Babcock and Wilcox B&W SCR

Zero or erratic AIG flow almost always means a stuck control valve, plugged nozzle, or cold vaporizer. Verify vaporizer temperature, check valve positioner output, and inspect the injection grid nozzles.

~90 min7 steps

How to diagnose catalyst deactivation and declining NOx efficiency on a Babcock and Wilcox B&W SCR

Gradual NOx efficiency loss that requires increasing ammonia to compensate is a sign of catalyst deactivation. Pull a catalyst sample for activity testing and check for arsenic or alkali poisoning.

~120 min7 steps

How to diagnose high stator winding temperature on a GE Gen6 / Gen8 generator

Elevated stator winding temperature with normal load usually means reduced cooling water flow or a blocked cooling passage. Check cooling water flow rate, inlet temperature, and compare RTD readings across all stator slots.

~60 min7 steps

How to clear Mazatrol Alarm 4 (Emergency Stop) on a Mazak VTC-200

Find which E-stop button is depressed (operator panel, side door, or remote), reset it, then clear the alarm from the Mazatrol screen.

~5 min4 steps

How to diagnose bearing noise and vibration on a Baldor Super-E motor

Vibration is most often a worn bearing. Listen for grinding, log a vibration reading, and plan a bearing replacement during the next planned outage.

~30 min7 steps

How to fix overheating and excessive current draw on a Baldor Super-E motor

Overheating with high current is usually mechanical overload or supply phase imbalance. Measure phase currents, check the load, and verify supply voltage balance is within 1%.

~30 min7 steps

How to detect and respond to a hydrogen gas leak on a GE Gen6 / Gen8 generator

Declining hydrogen purity or elevated makeup demand signals a leak. Check the shaft seal oil system first since shaft seals are the most common hydrogen leak path on large generators.

~120 min7 steps

How to clear catalyst plugging and high backpressure on a Babcock and Wilcox B&W SCR

Rising backpressure on an SCR catalyst bed is almost always ash or soot accumulation. Trigger soot-blowing, inspect inlet baffles, and schedule a catalyst wash if the differential pressure stays high.

~60 min7 steps

Related learning

Foundational explainers for techs and plant managers working the floor across any of these industries.

Electrical Fault Finding: Step-by-Step Diagnosis Guide

Electrical faults cause 30% of unplanned downtime. This systematic fault finding guide, visual inspection → voltage checks → component isolation → testing, helps you diagnose faults in minutes, not hours.

Hydraulic System Troubleshooting Guide: Fix Failures Fast

80% of hydraulic failures come from just 3 causes: contaminated fluid, overheating, or internal leaks. Stop guessing, use this step-by-step diagnostic sequence to find the root cause in minutes, not hours.

Vibration Analysis Basics: What Your Equipment is Telling You

Every rotating machine vibrates. The pattern of that vibration tells you whether bearings are wearing, shafts are misaligned, or components are out of balance. Learning to read vibration data catches 90% of rotating equipment failures weeks before they happen.

Motor Troubleshooting: From Symptoms to Fix

Electric motors make up 70% of industrial electricity consumption and are involved in most production lines. When one trips, overheats, or vibrates, you need a fast, structured diagnostic path. This guide maps symptoms to likely causes so you reach the fix faster.

PLC Fault Finding: A Technician's Quick Reference

When a PLC faults, production stops and everyone looks at the maintenance technician. Knowing how to read fault codes, check I/O status, and trace logic in a ladder diagram gets you from alarm to fix in minutes instead of hours. This reference covers the essentials.

Bearing Replacement: When, Why, and How to Do It Right

Bearings are the most commonly replaced component in industrial machinery. Yet 16% of premature bearing failures come from improper installation: wrong fit, contamination during mounting, or inadequate lubrication at startup. This guide covers the full process from selection to run-in.

Shaft Alignment Fundamentals: Precision That Prevents Failure

Misalignment is the second leading cause of rotating equipment failure after lubrication problems. Laser alignment takes 30 minutes and prevents months of accelerated wear on bearings, seals, and couplings. This guide covers the basics of angular and offset misalignment correction.

What is Root Cause Analysis (RCA)? A Practical Guide for Maintenance Teams

Most teams fix symptoms and move on. RCA forces you to find the actual failure point so the same problem stops showing up every month. Here is how to run one that produces real answers.

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