EMTOS Quarterly Preventative Maintenance Report
This quarterly preventative maintenance shall be performed to ensure the equipment operates reliably and safely between annual inspections. Inspectors should check all critical systems, verify proper operation of controls and safety devices, clean accessible components, inspect for wear damage, and document any issues for corrective action.
Envent Corporation
11/13/2025
EMTOS Quarterly Preventative Maintenance Report
This quarterly preventative maintenance shall be performed to ensure the equipment operates reliably and safely between annual inspections. Inspectors should check all critical systems, verify proper operation of controls and safety devices, clean accessible components, inspect for wear damage, and document any issues for corrective action.
Procedure Max Score: 172
EMTOS Quarterly PM
Unit #
Date
License Plate #
Inspectors
Unit Hours Start
Meter name
Unit
Air Compressor Hours Start
Gas Meter Start
No Power on Unit: Generator disconnected
Trailer
Check tires for proper inflation and dry rotting or damage.
Inspect all lights for proper operation (running lights, turn signals, brake lights).
Pull break away wire and verify the trailer breaks work by driving truck forward.
Inspect leg stands and grease Zerk fittings.
Check firebox to trailer bolts and holes for integrity.
Vaporizer
Check vaporizer thermocouple and make sure connections are secure (recrimp if necessary).
Check controller to ensure the knob can be fully turned into all positions.
Check silicone integrity around pilot ignitor transformer.
Open inlet Y strainer to check for propane butter. Depressurize line before breaking.
Remove 6-screw top cover to inspect refractory and doughnut gasket. Verify gasket is seated properly and clear of tank spacing.
Main Electrical Panel
Tighten every wire termination to 1.2 Nm torque.
Remove BMS and check terminations.
Check for open holes.
Signs of rust or water.
Inspect panel door gasket & conduit opening integrity.
Add desiccant packs if missing or replace if saturated.
Inspect wire condition (no wire rubbing against sharp edges).
Ensure spiral wire wrap is placed correctly to protect wires.
Ensure wire tie downs are operational, replace if necessary.
Ignitor Panel
Tighten every wire termination to 1.2 Nm torque
Check for open holes in each panel.
Signs of rust or water.
Inspect panel door gasket & conduit opening integrity.
Add desiccant packs if missing or replace if saturated.
Inspect wire condition (no wire rubbing against sharp edges)
Ensure spiral wire wrap is placed correctly to protect wires.
Ensure wire tiedowns are operational, replace if necessary.
Auxiliary Panel
Tighten every wire termination to 1.2 Nm torque
Check for open holes in each panel.
Signs of rust or water.
Inspect panel door gasket & conduit opening integrity.
Add desiccant packs if missing or replace if saturated.
Inspect wire condition (no wire rubbing against sharp edges)
Ensure spiral wire wrap is placed correctly to protect wires.
Ensure wire tiedowns are operational, replace if necessary.
Chart Recorder
Verify plug connections and wires are tight for power, thermocouples input 1 & 2, alarm outputs, output control and ground terminals.
Visually verify all ribbon cables are landed securely.
Verify input cards are seated correctly and free or corrosion or damage.
Rotary Gas Meter (Totalizer)
Drain oil in all three chambers and refill (left, right, and center).
Inspect and replace screen paper gasket on the inlet side and regular paper gasket on the outlet side.
California Only: Remove gas meter and send it to be calibrated and certified.
Flow Tubes
Remove all DS-300/400 and blow out with shop air, inspect, and reinsert or replace.
Firebox
Remove manway door and inspect refractory on floor, roof, walls, process inlet, and burner.
Burner
Verify burner cone integrity. Observe air gap on burner by removing burner. There should be at least ~1cm air gap around burner housing and cone.
Inspect burner damper and linkage assembly (wiggle linkage).
Inspect burner refractory discharge sleeve, check for cracks or broken studs.
Clean burner site glasses.
Combustion Blower
Visually inspect all blower mounting bolts for rust and tightness.
16. Maxon or Eclipse Valves (SSOV 1&2)
Inspect all valve covers and gaskets are in place and tight. If gasket integrity is compromised replace gasket.
Inspect landed wires on the valve terminal block are in good condition.
Ensure that all connections are tight and wiring is not frayed.
Open side cover plate and verify that no water, debris, or foreign mater. If there are signs of water intrusion, get with engineering to inspect further and give path forward on repairs.
Manual Butterfly Valves
4" Process Valve: Open gear assembly and grease gears.
Main Process Valve: Open gear assembly and grease gears.
Dilution Valve: Open gear assembly and grease gears.
Automatic Process Isolation Valve
Visually inspect mounting hardware and support brackets for signs of stress or wear.
Power on Unit: Connect Generator and Propane
Air Compressor
Ensure a 0-150 PSI Pressure Guage is installed before the regulator.
Verify the compressor stops at ~135 PSIG in the main tank.
Panel Light Check
Activate each button and switch to confirm it lights up when turned on.
Area Lights
Inspect all area lights by turning them on, replace bulbs as needed, and check for rust or water damage.
Chart Recorder
Verify the display powers up with no error codes or flickering.
Pen & Paper Operation: Correct date and time stamp, legible temperature recordings.
Temperature Accuracy: Compare temperature reading with High Limit Controller and verify readings are within 50F of each other.
Output Control: Test output control by placing in manual and driving the mod motor with the arrow keys.
Alarm Outputs: At 1400F, verify the top green panel light turns on, and the Process Isolation Valve opens.
Alarm Outputs: At 1550F, verify the top red panel light turns on. If temperature cannot be raised above 1550F, adjust Alarm setpoints A2S1 and A2S2 below current temperature to simulate.
Process Isolation Valve
Raise unit above 1400°F and verify valve fully opens and closes promptly. If the valve takes more than 30 seconds to close, replace the air dump valve.
Rotary Gas Meter
Check Pressure gauges on rotary meter and read out gauges. Check differential pressure between gauge (In./H20) behind of main gas (pancake) regulator and first gauge on gas meter is less than 10" wc. If greater, change gasket screen on Totalizer.
Drain moisture in airline to actuator and verify actuator opens valve once temperature is above 1400F
Process Valve
Check integrity of 4" process bypass valve and 10" process valve by bringing unit above 1400F with both valves closed and verify no suction at inlet
Burner
Verify that the modulating actuator moves to high during the 90 second high fire purge and moves to low when the BMS says to start.
Interlock Testing
Check all Interlocks on unit
High Limit Temperature
While BMS is going into purge, change the set point below the chart recorder temperature and verify a "stoppage" in BMS activity
While unit is running, lower high temperature set point below chart recorder temperature and verify burner shut down.
UV Scanner
While unit is running, remove UV scanner from unit. Do not expose to direct sunlight. Cover optical lens and ensure that the unit shuts down.
LEL Analyzer
Calibrate LEL in accordance with the procedures, verify analyzer is not bypassed by valves or by jumped wires behind LEL controller.
Test high LEL shutdown by lowering the setpoint to 0%. (Add a bias if current reading is 0%) Verify the unit shuts down. Remove any added bias.
Process Blower Pressure Switch
Open cover of pressure switch and verify that sensor is not jumped. Remove tubing from sensor and verify that interlock is tripped on BMS.
Verify on the pressure switch box that one wire is on common and one wire is on Normally Open.
Combustion Blower Pressure Switch
Open cover of pressure switch and verify that sensor is not jumped. Remove tubing from sensor and verify that interlock is tripped on BMS.
Verify on the pressure switch box that one wire is on common and one wire is on Normally Open.
FA Temperature Switch
Remove temperature switch. Wrap heating element around probe, set temperature to 410°F. Verify contacts open with ohms meter at 400°F. (Different from Test Fire)
Rotary Gas Meter
Drain oil in all three chambers and refill (left, right, and center).
Inspect and replace screen paper gasket on the inlet side and regular paper gasket on the outlet side.
Firebox
Remove manway door and inspect refractory on floor, roof, walls, process inlet, and burner.
Scan the entire exterior firebox wall with a temperature gun and record any areas exceeding 200°F.
Verify that the modulating actuator moves to high during the 90 second high fire purge and moves to low when the BMS says to start
PM Lead Closure Signature
PM Lead Sign Off
Quality Check Approval Signature (Shop Personnel)
Quality Check Sign Off (Shop Personnel)
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Source: Envent Corporation (Community Member)