How to build a preventive maintenance checklist with measurements

Most maintenance checklists share one weakness: every item is a “checked” box. The technician ticks the boxes, the form goes into a folder, and when the unit fails six months later nobody knows how it was actually running on the day of the visit. A tick says someone looked. It does not say what they saw.

A good checklist works more like an instrument. It records everything measurable as a number, knows where that number is acceptable, and says in advance who does what when a limit is crossed. This guide walks through building one.

1. Split by asset type and by job

One “general maintenance form” does not fit every machine. A cold room and a dishwasher need different readings. Build each checklist around two questions:

• For which asset type? Cold room, condensing unit, combi oven, air compressor, and so on.
• For which job? Preventive maintenance, breakdown close-out, pre-use operator check.

A breakdown close-out should be short: root cause found, work performed, photo of the replaced part, unit handed over running. A preventive maintenance list can be longer, but it should still take five to ten minutes. Nobody fills in a forty-item form carefully on site.

2. Pick the right type for every item

The item type decides how useful the answer will be. These are the types worth having:

Type	Use it for	Example
Yes / no	Whether a condition exists	Visible oil stain or leak sign
Pass / fail	Whether something meets its acceptance criterion	Fans quiet, blades intact
Checkbox	A task that was done	Condenser coil cleaned
Measurement	A value with a unit	Compressor current (A)
Number	A plain count	Run hours
Choice	One of fixed options	Leak detection method used
Text / note	Free description	Work performed
Photo	Evidence	After-cleaning photo

The rule is simple: never turn something measurable into a pass/fail item. Instead of “current normal”, record the current in amps. A value that is within limits today may be the first point of a rising trend three visits from now, and you only see that trend if you kept the number.

3. Put limits on readings, and know where each limit comes from

When a measurement item has a minimum and maximum, the checklist checks itself: an out-of-range answer is flagged the moment it is entered. Limits come from three kinds of source, and it matters which one you used:

• Regulation. Turkey’s Food Codex communiqué on quick-frozen foods requires the product to be at −18 °C or below at all points (Official Gazette, 18 Oct 2014). That gives you the maximum for a freezer’s internal temperature.
• Standards. For circuits up to 500 V, insulation resistance measured at 500 V DC should be at least 1.0 MΩ (HD 60364-6 Table 6.1, summary by EMO).
• Manufacturer or house practice. The familiar 0–4 °C band for chillers is HACCP practice; Turkey’s Food Hygiene Regulation requires temperatures to be monitored and recorded where needed but sets no number. The upper limit for compressor current is the value on the nameplate. Dishwasher wash and rinse temperatures come from the manufacturer too.

Label practice-based limits as such and compare them with the equipment manual. Some numbers everyone believes are “the law” turn out to be habit.

4. Keep required and photo items few and deliberate

Make every item required and technicians learn to answer whatever lets them through. Reserve “required” for answers without which the job cannot count as done: the unit runs, the key readings, anything safety related.

Photos work the same way. A photo is valuable where a dispute might come up later: a cleaned condenser, a hood duct before and after cleaning, the replaced part, the updated service tag on an extinguisher. A “general view” photo is usually a file nobody ever opens.

A skeleton for a refrigeration visit:

1. Unit running, no alarms — yes/no, required
2. Cabinet or room temperature — measurement (°C), required, limits from the unit’s setpoint
3. Suction and discharge pressure — measurement (bar)
4. Compressor current — measurement (A), required, maximum from the nameplate
5. Condenser coil cleaned — checkbox, required, photo required
6. Evaporator, drain and tray clear — pass/fail, required
7. Visible oil stain or leak sign — yes/no, required
8. Notes

If item 7 is “yes”, a leak check is due: Annex 5 of Turkey’s fluorinated greenhouse gas regulation lists oil stains among the signs that call for one. We covered how to keep those records in a separate post.

5. Decide in advance what happens out of range

Flagging an out-of-range value is not enough; someone has to act on it. For each critical reading, write down:

• What happens on site? Adjust the setting, stop the unit, tell the customer?
• Who hears about it? The maintenance lead, the site manager?
• Where does it go? A new service request, or a note on the work order?

A text item called “corrective action if out of range” is a good habit here. Corrective action is one of the seven HACCP principles anyway.

6. Keep the records

Turkey’s regulation on health and safety in the use of work equipment, Annex III, requires that all maintenance and repair records be kept for the equipment’s whole service life, and that the operator’s pre-use visual check be recorded (mevzuat.gov.tr). A paper form lost in a binder is not just untidy.

A light mode: readings without a work order

Not every reading is a maintenance job. Opening a work order for each daily cold room temperature or each forklift pre-use check only clutters your list. Use a separate, short recording checklist for these: three or four items, a couple of minutes, filled straight on the asset.

How this works in Saha

In Saha checklists are templates that support every item type above. A measurement item gets a unit, a minimum and a maximum, and an out-of-range answer is flagged automatically. When a template is added to a work order its items are copied as they are at that moment, so editing the template later never rewrites past records.

Technicians fill the checklist in the iOS or Android app, which keeps working without a connection on the work assigned to them. When they complete the job, Saha checks the completion rules: every required item answered, a photo on every photo-required item, no open part request. If anything is missing the work order stays open and the reasons are listed one by one.

For recurring readings like daily temperatures there are readings logs: the checklist is filled straight on the asset, with no work order. Say how often a log is expected and an overdue log shows on the asset. If you choose, an out-of-range value opens one service request for that asset and checklist, and repeat readings do not pile up duplicates. The ready sector templates (refrigeration, HVAC, electrical, generator/UPS, commercial kitchen, general service) come with checklists much like the examples here, which you adjust to your own values. Every record lands in the asset’s service history and can be exported as CSV.

A quick review

Before you put a checklist into use, ask:

• Is everything measurable recorded as a number?
• Is the source of every limit (regulation, standard, manufacturer, practice) known?
• Are the required items really the ones a job cannot be done without?
• Are photos asked for only where evidence matters?
• Is it written down who does what on an out-of-range reading?
• Can it be filled in within ten minutes?

If the answer to all six is yes, you no longer have a form to file. You have a record that tells you something about your equipment.