Troubleshooting

Organised by what you see on screen. If the exact wording is not here, check the Messages console first, since it usually already says what happened.

The Run Button Is Greyed Out

Hover it and a tooltip names the reason. There are only six.

TooltipMeaningFix
Loading databases…The built-in entries have not arrived yetWait a moment. It resolves on its own
Database failed to load. Switch to CSV mode or reloadThe database request failedReload the page. If it keeps failing, switch both data sources to User Defined and supply your own curves
No cell selected from databaseCell Data Source is Database, but nothing is selectedClick Browse database… under Cell Venting Data and pick an entry
No valve selected from databaseSame, for the valveClick Browse database… under Pressure Relief Valve Characteristic
Venting curve CSV not loadedCell Data Source is User Defined, with no valid fileUpload a venting curve and complete the column mapping
PQ curve CSVs not fully loadedValve Data Source is User Defined, with one or both curves missingBoth curves are required, before and after opening
Temperature CSV not loadedTemperature Mode is Given Test Data, with no valid fileUpload a temperature curve, or switch back to Assumed Constant

The common thread: the button only enables when the solver has everything it needs. It is not hiding a problem, it is refusing to send an incomplete case.

CSV Upload Errors

All of these appear immediately on upload, before anything is sent anywhere. Row numbers count the header as row 1, so they match what your editor shows.

Structure

MessageCause
CSV must have a header row and at least one data row.The file is empty or has one line
CSV must have at least two columns.Only one column was found. Check that the file is comma separated, not semicolon or tab separated
CSV column headers must be unique.Two columns share a name. Columns are selected by name, so duplicates are ambiguous
CSV needs at least 2 data rows for interpolation.One data row cannot define a curve
Row N has X columns but header has Y.A ragged row, often a stray trailing comma or an embedded line break
Row N, column "H": "v" is not a finite number.A blank cell, a text value, a unit suffix inside the cell, or a thousands separator
File too large (X MB, limit 2 MB).Downsample before uploading. A curve does not need tens of thousands of points
Each field must map to a different CSV column.The same column was mapped to both fields

Two frequent causes worth calling out. A spreadsheet exported with a locale that uses commas as decimal separators produces cells like 1,25, which parse as a broken row. And a cell containing a unit, like 10 kPa, fails because the unit belongs in the column mapping, not in the data.

Ordering

MessageApplies toMeaning
... must be strictly increasing (failed at row N).Time, and valve pressureTwo identical or out of order values. Each time and each differential pressure may appear only once
... must be non-decreasing (failed at row N).Gas moles, and valve flowThe value fell. A cumulative curve cannot go down, and flow cannot fall as pressure rises
Time values must start at ≥ 0 s.TimeNegative time
Gas mole values must be ≥ 0.Gas molesNegative gas amount
Pressure values must be ≥ 0.Valve pressureNegative differential pressure
Flow rate values must be ≥ 0.Valve flowNegative flow
Row N: temperature must convert to positive Kelvin.TemperatureA value below absolute zero once the unit you selected is applied. Usually the wrong unit was chosen

The most common of these is a cumulative gas column that dips slightly, from measurement noise near zero. Clean the data rather than working around it: a dip means a negative generation rate, which is not physical.

Messages in the Console

MessageMeaning
Databases loaded: 2 cells, 2 valves.Normal startup
Input parameters changed. Please run simulation again.Results were cleared because an input that affects the physics changed. Expected behaviour, not an error
Your session has ended. Please sign in again.Your sign-in is no longer valid, usually because you signed out elsewhere or the session expired. Sign in again. Your inputs stay on screen
This chat result has expired. Recompute it from the workspace.An AI result card is too old to apply. Ask the assistant to run it again
Load failed: Not a valid JSON file.The chosen file is not JSON
Load failed: Config is for "X", not PRV-Sizing.A configuration saved by a different tool
Load failed: No recognizable parameters in this file.Valid JSON, but nothing matching a known field

You Hit a Usage Limit

A dialog names the limit and offers to upgrade. Nothing is lost, and your inputs stay exactly as they are. You can still save your configuration to a file with no allowance remaining.

If you upgrade in another tab, return to the tool’s tab rather than reloading. It rechecks your plan when the tab regains focus.

See Plans and Usage Limits.

You Are Being Rate Limited

Separate from running out. The rate limit caps how quickly solves can be submitted, not how many you get. Wait a moment and try again.

A Solve or Export Failed

If the failure is not one of the cases above, the tool offers to send diagnostics. This uploads the exact setup that failed, including any curves you uploaded, so we can reproduce the problem directly.

It asks every time and sends nothing unless you click send. This is the only route by which simulation data reaches our servers. If the setup is one you cannot share, decline and write to support@thermosketch.com describing what you were doing instead.

Failed actions do not consume your allowance.

Results Look Wrong

Before assuming a defect, check these in order. Nearly every case is one of them.

The peak is enormous. You are probably reading Absolute Peak Pressure as if it were relative. The absolute value includes about 101 kPa of atmosphere. Read the relative figure. See Reading the Results.

Pressure barely rises. Check Number of Venting Cells, and check the units on your venting curve. A curve in millimoles read as moles gives a thousand times too little gas.

Pressure is still climbing at the right edge of the chart. Simulation Time is too short and the peak has not happened yet. Extend it.

The valve never opens. Compare its opening pressure against the peak the pack reaches. If the peak is below the setpoint, the valve was never needed.

Everything changed after a unit switch. It should not have. Switching a unit converts the displayed value and leaves the physical value alone. If a number looks wrong after a switch, check whether the original value was typed under a different unit than you intended.

Nothing Here Matches

Write to support@thermosketch.com. The most useful thing you can attach is your saved configuration file, since it reproduces your case exactly. Save / Load → Save Configuration.