What this is
What is a reefer unit check?
What is a reefer unit check?
It is a pre-load inspection of a trailer or truck refrigeration unit covering starting and running, fuel adequacy, temperature control and alarm history. It is completed by the driver before a temperature controlled load goes on, not after a problem is already visible on a monitor.
How does it differ from the Refrigeration Unit Service Record (FLT-047)?
This check is an operational pass/fail done by the driver before loading. FLT-047 is the maintenance record for scheduled servicing, parts and technician sign-off. A unit can pass this check and still be due for its next FLT-047 service.
Why does fuel level get its own scored field?
A reefer engine that runs out of diesel mid-route stops cooling entirely, with no alarm distinguishing it from a mechanical failure until the load is already warm. It is one of the few failure modes this check can eliminate outright rather than just flag.
Scope
When is a reefer unit check required?
This check confirms the unit is fit to run a specific load, right now. It is not the maintenance file, the trip's temperature log, or the leak investigation — those live in the templates it links to.
Use this template when
- A temperature controlled load is about to go on the trailer or truck
- The unit has been idle, off power, or unused since its last check
- A driver or dispatcher needs a documented go/no-go before departure
- The reefer has just come back from service and needs a functional re-check
- An operator licence or customer audit asks for evidence the unit was verified before loading
Do not use it for
- Refrigeration Unit Service Record, which the scheduled maintenance and repair history for the unit itself.
- Driver Vehicle Inspection Report, which the pre-trip and post-trip inspection of the tractor or rigid vehicle.
- Trailer Inspection, which checks trailer coupling, brakes, lights, tyres, doors and structure.
- Annual Vehicle Inspection, which the yearly statutory inspection of the vehicle.
- Anything outside KnowFleet, which belongs in the workspace that owns that process
Compliance mapping
Which FSMA Sanitary Transportation rule requirements does this satisfy?
The Sanitary Transportation rule does not name a 'reefer check' by that phrase, but it does require the equipment and procedures behind one. The clause map below shows which requirement each section of this template is standing in for.
| Clause | Requirement | Where it lands |
|---|---|---|
| 21 CFR 1.908(a)(1) | Vehicles and transportation equipment kept in adequate sanitary condition to prevent food from becoming unsafe | Unit operation |
| 21 CFR 1.908(b)(1) | Equipment capable of maintaining the temperature required for the food being carried | Unit operation |
| 21 CFR 1.908(b)(2) | Vehicles and equipment precooled where the shipment requires it | Result |
| 21 CFR 1.908(b)(3) | Temperature controls verified as functioning before and during transport | Control and monitoring |
| 21 CFR 1.908(b)(4) | Written procedures for monitoring and recording temperature during transport | Header |
| 21 CFR 1.908(c) | Investigation and corrective action where temperature control equipment is found to be non-functioning | Result |
| 21 CFR 1.912 | Records kept in a manner that permits an inspection to verify compliance | Header |
What it does not cover
- Setpoint Locked Or Controlled, which recorded as Open with no note on who has access to change it mid-route.
- Fuel Level Adequate For Trip, which marked Marginal against a trip length nobody checked against range.
- Any Refrigerant Leak Suspected, which answered Yes with no Leak Record ID entered against it.
- Temperature Sensors Calibrated, which marked Overdue and left with no corrective note or replacement plan.
- Unit Fit For Loading, which marked After Repair with no record of what the repair addressed or who verified it.
Global
Reefer Unit Check requirements by country
Cold chain trucking crosses borders more often than most fleet operations, and the instrument behind this check changes with the lane, not just the operator's home country.
FSMA Sanitary Transportation of Human and Animal Food rule, 21 CFR Part 1 Subpart O
Shippers, carriers and receivers share responsibility for vehicle and equipment adequacy; the carrier's pre-load check is the documented evidence a carrier actually did its part.
A failed or skipped check on a load that later excursions is the first document an FDA or customer investigation asks for.
Safe Food for Canadians Regulations, transportation requirements
Broadly parallel to the US rule — equipment must be capable of maintaining required conditions and be verified before use.
Cross-border reefer runs need this check on both legs; a US-only paper trail does not satisfy a CFIA request on a Canadian-registered load.
ATP Agreement (temperature-controlled carriage of perishable foodstuffs) and Regulation (EC) 852/2004
Equipment must carry a valid ATP certification and be shown to be functioning correctly for the class of transport it is rated for.
A unit check here is the operational counterpart to the ATP plate — the plate says the unit can do the job, this check says it did on the day.
How to complete it
How to complete a reefer unit check, step by step
The fields are simple to fill in. The judgement is in deciding what counts as good enough to load against.
Adequate is relative to trip length and ambient temperature, not a fixed fraction of the tank. A driver marking Adequate on a short urban run and a driver marking it on a twelve-hour interstate leg are answering different questions with the same word — the completing driver needs the trip context in front of them, not just the gauge.
Locked or password controlled only satisfies the intent of the field if the password is not shared or written on the dash. A unit answered Locked that any driver can still override defeats the reason the field exists — this is a control to verify, not just a switch position to read.
A refrigerant leak suspicion tied to a unit that is also failing to reach setpoint or showing intermittent defrost is a different risk than an isolated smell with normal performance otherwise. The template records both facts separately; the completing person has to decide whether they add up to a no-load call.
A unit that reaches setpoint in the yard air but has not held it for the settle time a chilled load needs is not really precooled — it is just cold at the moment of loading. Marginal exists precisely for that gap, and it should be used rather than rounded up to Yes to keep the load moving.
What auditors find
Most common reefer unit check findings
The findings this check produces recur across fleets running temperature controlled freight. Six of the most common are below.
| Finding | Clause | What fixes it |
|---|---|---|
| Setpoint left unlocked with no password control | 21 CFR 1.908(b)(3) | Lock the controller or apply password control as standard fit, and treat an open setpoint as a fail rather than a note. |
| Unit passed on start-up with fuel level not checked against trip distance | 21 CFR 1.908(a)(1) | Require trip distance or estimated hours before the fuel field can be answered, so 'adequate' has a basis. |
| Refrigerant leak suspected but no leak record raised | 21 CFR 1.908(c) | Make the Leak Record ID field mandatory, not just conditionally shown, whenever a leak is suspected. |
| Temperature sensor calibration overdue at time of check | 21 CFR 1.908(b)(3) | Block the check from closing as Pass while calibration status reads Overdue; route to Action Required instead. |
| Data logger intermittent and previous trip data not downloaded | 21 CFR 1.912 | Treat a failed download as a gap in the record, not a minor note — download before the next trip overwrites the buffer. |
| Unit marked fit for loading 'after repair' with no verification step recorded | 21 CFR 1.908(c) | Require a second signature or a linked work order reference before After Repair can be selected as the fit-for-loading answer. |
Case in point
Case in point: the fuel gauge that read half full
A reefer trailer was checked at 6am, started cleanly, reached setpoint in four minutes, and was marked fit for loading. Fuel was read as Adequate off a gauge showing roughly half a tank, against a planned nine-hour run. The unit ran out of diesel at hour seven, sixty miles from the delivery point, on a load of chilled dairy.
Nothing on the check was falsified. The gauge reading was accurate and the unit genuinely started and ran. The gap was that 'adequate' was judged against the tank, not the trip — the same answer would have been correct for a two-hour local delivery and wrong for the run actually planned. The fix was procedural, not technical: require the planned trip length on the check before the fuel field can be answered.
The template
The template, field by field
The form exactly as it installs. Every field, option, score and conditional rule is editable, and the links to other templates come with it.
4 sections
- Reference
- FLT-004
- Archetype
- Inspection
- Record ID
- INSP-2026-000
- Scoring
- Pass or fail
- Direction
- High is good
- Singleton
- No
- Basis
- FSMA Sanitary Transportation rule
- Links
- Links Asset; feeds Cold Chain
- Tags
- Fleet, Cold chain
- Sections
- 4
- Fields
- 51
- Follow up fields
- 4
- Repeating sections
- 0
- Links out
- 5
Header
13 fieldsCheck ID*
Auto sequence. Format REF-2026-000.
The record's own ID. Other templates point at this value.
Status*
Drives who this goes to next.
- Planned2 pts
- In progress2 pts
- Complete3 pts
- Deferred0 pts
- Open0 pts
- Closed3 pts
- Overdue0 pts
Date and Time*
Completed By*
Site*
Site ID*
Format SITE-000.
Links to FDN-001 Site ID
Vehicle*
Asset ID*
Format AST-0000.
Links to FDN-002 Asset ID
Unit Number
The number painted on the door, which is what drivers actually use.
The Unit Runs The Whole Load
A reefer failure on a full trailer of chilled product is a five figure loss before anybody notices. Check it before loading, not after the alarm.
Unit Make And Model
Check Type*
Running Hours
Unit operation
12 fieldsUnit Starts And Runs*
- Yes3 pts
- Difficult start1 pt
- No0 pts
Fuel Level Adequate For Trip*
A reefer running out of fuel mid trip is the most common and most avoidable excursion cause.
- Full3 pts
- Adequate2 pts
- Marginal0 pts
Oil And Coolant Levels*
- Correct3 pts
- Topped up2 pts
- Low0 pts
Belts And Hoses Condition*
- Good3 pts
- Worn1 pt
- Defective0 pts
Condenser And Evaporator Clean*
- Clean3 pts
- Some debris1 pt
- Blocked0 pts
Airflow Unobstructed*
- Yes3 pts
- Partly1 pt
- Blocked0 pts
Refrigerant Charge Adequate*
- Yes3 pts
- Low0 pts
Any Refrigerant Leak Suspected*
- No3 pts
- Yes0 pts
Leak Record ID
Links to ENV-024 Record ID
Defrost Cycle Functions*
- Yes3 pts
- Intermittent1 pt
- No0 pts
Unit Reaches Setpoint*
- Yes3 pts
- Slowly1 pt
- No0 pts
Pull Down Time Acceptable*
- Yes3 pts
- Slow1 pt
- No0 pts
Control and monitoring
9 fieldsSetpoint Correct For Product*
- Yes3 pts
- Adjusted2 pts
- No0 pts
Setpoint Value*
Setpoint Locked Or Controlled*
Drivers adjusting setpoints to save fuel is a known cause of excursions.
- Locked3 pts
- Password controlled3 pts
- Open0 pts
Temperature Sensors Calibrated*
- Yes3 pts
- Overdue0 pts
Calibration ID
Links to MNT-060 Calibration ID
Data Logger Functioning*
- Yes3 pts
- Intermittent1 pt
- No0 pts
Alarm Function Tested*
- Yes3 pts
- No0 pts
Remote Monitoring Connected
- Yes3 pts
- No1 pt
Previous Trip Data Downloaded*
- Yes3 pts
- No0 pts
Result
17 fieldsItems Assessed*
Excludes anything marked N/A.
Items Failed*
Score Percent*
Calculated on submission. High is good. N/A items leave the denominator.
Result Band*
- Pass3 pts
- Caution1 pt
- Fail0 pts
Completeness Percent*
How much of the template was actually answered. A high score on a half completed form is not a high score.
Unit Fit For Loading*
- Yes3 pts
- After repair1 pt
- No0 pts
Pre-Cool Required Before Loading*
Pre-Cool Temperature Achieved
- Yes3 pts
- Marginal1 pt
- No0 pts
Action Required*
Raise the action record, then enter its reference here.
- No2 pts
- Yes0 pts
Priority
- High0 pts
- Medium1 pt
- Low3 pts
CAPA ID
Format CAPA-2026-00000.
Links to FDN-014 CAPA ID
Action Owner
Next Due*
Driver*
Signature*
Transport Supervisor*
Second Signature*
FLT-004 · record IDs look like INSP-2026-000 · Links Asset; feeds Cold Chain
Open in KnowellaRun it with agents
From a document you fill in to a programme that runs itself
The check itself takes minutes. Making sure it happens before every load, and that a fail actually stops the load rather than just getting logged, is where fleets lose the thread.
Holds the reefer unit check against the asset register, blocks a load from being dispatched against a unit with an open fail, and keeps the check linked forward to Cold Chain.
Takes a fail or a CAPA raised on this check straight into a work order, and feeds calibration and service due dates back so the check itself flags them before they lapse.
Watches for the pattern this check is meant to prevent — repeated marginal fuel or unlocked setpoint answers on the same unit — and surfaces it before an excursion, not after.
Coordinates the crew across these workspaces, rolls completion and exceptions into one view, and holds every write for your approval before it touches a record.
This template lives in KnowFleet — fleet and transport. Drivers, vehicles, hours, cargo securement and operator licence compliance.
Meet KnowFleet→Glossary
Reefer Unit Check definitions and key terms
- Reefer
- A refrigerated trailer or truck body with its own independent cooling unit, as distinct from an ambient trailer.
- Setpoint
- The target temperature the reefer controller is instructed to hold for the product being carried.
- Pull-down time
- How long the unit takes to bring the trailer from ambient temperature down to setpoint.
- Precooling
- Running the unit to bring the trailer to setpoint before the load goes in, so the product itself does not have to absorb that cooling load.
- Excursion
- A period where the carried product's temperature moves outside the range required for that product, whether or not an alarm fired.
FAQ
Frequently asked questions about reefer unit check
Who normally completes a reefer unit check?+
The driver, immediately before loading. It is written to be completed in the yard in a few minutes, not by a technician after the fact.
Does passing this check mean the unit needs no service?+
No. It confirms the unit is fit for this specific load today. Scheduled servicing, parts replacement and technician-level work sit in the Refrigeration Unit Service Record, FLT-047.
What happens if the unit fails the check?+
The template routes to Action Required and a CAPA reference. Depending on severity, that can mean holding the load, swapping trailers, or scheduling repair before the trip departs.
Why is fuel level scored separately from the unit starting?+
A unit can start, run and reach setpoint perfectly on a nearly empty tank. Fuel adequacy is the field that actually predicts whether it will still be cooling at the far end of the trip.
Does a suspected refrigerant leak automatically fail the check?+
It should be treated as a stop condition pending investigation, not logged and ignored. The template links it to a record ID specifically so the leak gets tracked to resolution rather than re-answered Yes on every subsequent check.
How does this check connect to Cold Chain records?+
It feeds Cold Chain downstream — the unit's fitness for loading, setpoint and monitoring status at departure are the baseline that any later temperature excursion record gets compared against.
Keep going
Related templates and programmes
Industries this is written for
Programmes this belongs to
Used together in Fleet and Driver Compliance
Transport Provider Assessment
Assesses a haulier for licensing, driver management, vehicle standards, temperature capability and load security
Driver Vehicle Inspection Report
The pre-trip and post-trip inspection a driver completes on a commercial vehicle
Annual Vehicle Inspection
The yearly statutory inspection of a commercial vehicle
Trailer Inspection
Checks trailer coupling, brakes, lights, tyres, doors and structure
Vehicle Defect Report
Reports a defect found on a vehicle at any time, not just during a scheduled inspection
Roadside Inspection Record
Records a roadside inspection by an enforcement officer, including any violations and out of service orders
More in Vehicle Inspections
Driver Vehicle Inspection Report
The pre-trip and post-trip inspection a driver completes on a commercial vehicle
Annual Vehicle Inspection
The yearly statutory inspection of a commercial vehicle
Trailer Inspection
Checks trailer coupling, brakes, lights, tyres, doors and structure
Vehicle Defect Report
Reports a defect found on a vehicle at any time, not just during a scheduled inspection
Roadside Inspection Record
Records a roadside inspection by an enforcement officer, including any violations and out of service orders
Tyre Condition Record
Records tyre tread depth, pressure and damage across the vehicle
Written and reviewed by
Siddarth Singh
Founder & Chief Executive Officer, Knowella
Certified Safety Professional and industrial and systems engineer with more than a decade inside food supply chain, freight and manufacturing operations. This page was written against the current text of the standards it cites, not against secondary summaries of them.
- Certified Safety Professional (CSP), Board of Certified Safety Professionals
- MBA, University of Chicago Booth School of Business
- MS and BS, The Ohio State University, Industrial and Systems Engineering
- Six Sigma Black Belt
Sources and last review. Reviewed 16 August 2026 against:
- FSMA Sanitary Transportation of Human and Animal Food rule — 21 CFR Part 1, Subpart O
- 21 CFR 1.908 — Requirements for vehicles and transportation equipment
- 21 CFR 1.912 — Records requirements
- ATP Agreement — Carriage of Perishable Foodstuffs
This page is general guidance, not legal advice. Confirm requirements with your jurisdiction’s regulator.