Why two sheets, not one
Most plants already write readings down somewhere: a notebook in the pump room, a whiteboard, a spreadsheet that only one person understands. What is usually missing is the link between the routine numbers and the breakdowns. A bearing temperature that crept up by eight degrees over two weeks means nothing on its own. Next to a failure record that says “bearing seized, 14 hours down”, it becomes the warning you missed.
That is why the template has two tables. The readings log is the routine: same columns every shift, same units, one row per unit per reading. The failure log is the exception: what broke, why, how long it was down, what parts went in and what it cost. Keep them in the same Google Sheet, on two tabs, and the pattern becomes visible.
What to log for each type of equipment
| Equipment | Readings that usually matter most |
|---|---|
| Pumps | Suction and discharge pressure, flow, motor current, vibration, bearing temperature, running hours |
| Boilers | Supply and return temperature, pressure, fuel consumption, flue gas temperature, O₂, feed water hardness |
| Heat exchangers | Inlet and outlet temperatures on both sides, pressure drop on both sides, flow |
| Chillers / AC | Chilled water supply and return, condenser temperatures, compressor current, refrigerant pressures |
| Fans / AHUs | Air flow or fan speed, filter pressure drop, motor current, vibration, supply air temperature |
| Air compressors | Discharge pressure and temperature, motor current, oil temperature, load/unload hours, dew point |
Fewer columns logged every time beat many columns logged when someone remembers. If a reading never changes a decision, drop it.
A few rules that keep a log useful
Use the same units in every row and put them in the column header, never in the cell. Write numbers, not words: “OK” cannot be plotted. Log the time, not just the date, because a pump that runs hot only on the night shift is telling you something. And give each unit a fixed tag (P-1, P-2) so its history stays in one place even when people change.
The failure log needs one discipline above all: record the downtime in hours and the cost, even roughly. Those two columns are what turn “that pump is always breaking” into a number someone will approve a budget for. The critical spare parts calculator uses exactly these figures.
How to paste into Google Sheets
Click “Copy for Google Sheets”, open a sheet (the button next to it creates a new one), click cell A1 and paste. The columns split automatically. Do the same for the failure log on a second tab. If you prefer files, download the CSVs and use File → Import in Google Sheets or open them in Excel.
Frequently asked questions
Is the sample data real?
No. The sample rows are generated in your browser to show how a filled-in log looks, and every sample row is marked SAMPLE. Some values drift slowly on purpose, for example a bearing temperature creeping up, so you can see what a developing problem looks like. Delete them before you start logging real readings.
Can I use this in Excel instead of Google Sheets?
Yes. Download the CSV files and open them in Excel, LibreOffice or any other spreadsheet. The copy button also works for pasting into Excel.
How often should readings be taken?
For equipment that runs continuously, once per shift is a common practice and catches most slow trends. For equipment that runs part time, log at each start or once a day. Critical machines with online monitoring may not need manual readings at all, but a failure log is still worth keeping.
Is anything I enter sent to a server?
No. The template is built in your browser. Nothing you type on this page is sent anywhere.
More free engineering tools
Free, no sign-up, built by an engineer who runs heating and water supply networks.