Most problems in HeatAlgo have one of a few known causes and a short message that says what to do. This troubleshooting article collects them in one place: saving and version conflicts, emails, PDF, units, Algo, links, the account and the browser. Payment problems are covered separately in subscription, invoices and payments.
Saving and version conflicts
Saving is automatic. Every module saves a moment after a change and before you leave the screen. The "Saving..." indicator shows a save in progress. There is no save button.
"The changes could not be saved. Check your connection" - you lost your connection for a moment. Your edits are safe, and the save retries on its own when the connection is back. Do not close the tab until the message goes away.
"Project was changed on another device" - the server has a newer version of the module: saved from another device, from a second browser tab, or by Algo in automatic mode. Refresh the page (radiant floor heating has a "Load newer version" button). The changes in your tab from before the conflict will not overwrite the newer ones. To avoid conflicts, edit one project in one tab at a time. The same goes for Algo: if Algo saved a change while you had unsaved values in the form, the form refreshes to Algo's version.
"This module's data is too large to save." - a rare case with very large projects. Remove rooms or floors you do not need, and write to us.
A new version of the app and the session
"A new version of HeatAlgo is available - reload to switch to it" - click "Reload"; your changes are saved. If uploading a floor plan ended with "The app is being updated", refresh the page and upload the file again.
"Session expired. Please sign in again" - the browser session ended. After you sign in you return to the same place. "Project not found" after a refresh - the project was deleted (maybe on another device) or the link is out of date.
Units look wrong
The app shows numbers in your account's units. An account created from the US starts in imperial (ft, ft², °F, Btu/h, gpm); an account created elsewhere starts in metric. If you see meters and want feet, or the other way around, switch under "Units" in Settings, in a wizard's "Module settings", or in the radiant floor heating toolbar menu. The choice is for your whole account.
Some things stay metric on purpose: nominal pipe sizes such as "16×2 mm", kWh, percentages and dB(A). The tubing spacing shows in inches with the millimeters kept. The PDF report prints metric units for every account for now. The client form is a public page and always stays metric. Every calculation is metric under the hood, to EN 12831-1 and EN 1264, so switching units never changes a result. More in settings, logo and notifications.
Emails that do not arrive
- The sign-up confirmation link or the password change link - check spam, then use "Send the link again" on the "Check your inbox" screen. The password link is valid for 24 hours.
- The client form invitation - the form card shows "The invitation did not arrive" when the message was rejected. Check the address and send again (once a day), or copy the link and send it another way.
- The notification about a completed form - check in Settings that the "Client forms" category has email turned on. In the app the notification is always in the bell.
- The invoice - Stripe sends it in a separate email. You also find it on the "Billing" page under "Invoices and card at Stripe".
Links that expired
- The client form link works for 90 days from sending. After that your client sees "This link has expired". Send the form again from the project; answers submitted earlier are saved.
- The password change link works for 24 hours - ask for a new one.
- "This form has already been sent" - your client is trying to open the form after sending it back. If they need to correct something, use "Send back for fixes" in the project.
PDF and export
- "PDF generation is temporarily unavailable" - an outage on our side; try again in a moment.
- "Open the floor-plan preview before exporting", "The floor plan changed since the preview was taken" - these are about the radiant floor plan. Open the preview again and download once more.
- "The floor-plan image could not be prepared" - make the backdrop scan smaller or pick a smaller print scale.
- "The project has errors to fix - some figures in the export may be blank." - fix the fields from the "to fix" chip.
- "The printable floor plan is part of the report" - the project is not unlocked.
- "Floor plan file is too large (max 25 MB)", "The PDF is too large (max 20 MB)", "This PDF could not be read" - make the file smaller or save the plan page as PNG.
More in the article on reports.
Algo and reading documents
- "Algo is temporarily unavailable", "The AI service is temporarily overloaded", "The answer took too long" - try again in a moment. With documents, send fewer files at once.
- "This month's Algo budget has been used up" - this month's allowance is used up. It resets on the first day of the month, and a report or a subscription gives a larger one.
- "Algo reads PDF files and JPG, PNG and WebP images" - it will not read another format; "I can take 5 files and 20 MB at once".
- "The data in these materials could not be read" - try a clearer scan or photo.
- "Algo is currently switched off" - we turned the assistant off on our side; the calculations work normally.
More in Algo, the AI assistant.
Calculation stopped
"Fill in the missing data to get a result" and the chip labeled "Blocks the calculation" - the module will not compute the result until you complete the fields it points to. The "Fix" button takes you to each of them. In the heat loss calculation the usual blockers are no rooms, a room without walls, roofs or floors, a heated area over the limit, and missing airflows with mechanical ventilation. In ventilation they are a terminal without a room, no unit, or a loop in the ducts. In heat pump sizing they are no area or no radiator dimensions. A module linked to the heat loss calculation shows the list of its blockers with a "Fix in the calculator" button.
Account
- "Your account is blocked" - nothing has been deleted; write to us from the field on that screen.
- "Invalid email or password", "Email address has not been confirmed", "Too many attempts" - see account, sign-in and password.
- Projects gone after signing in - check that you signed in with the same email address you created them with. Projects do not disappear when your plan changes or after a subscription ends.
Browser and device
HeatAlgo works in current versions of Chrome, Edge, Firefox and Safari. The minimum versions are Chrome 98 and Safari 15.4 - an older browser may show a blank screen after you sign in, so update it. Drawing in radiant floor heating and the "Ducts" step in ventilation need a computer or a tablet. If the drawing is slow, lower the resolution of the backdrop scan before you upload it. On a short screen (a phone turned sideways, a small laptop), if a dialog's buttons are out of sight, scroll inside the dialog - the app fits on the screen, and tall dialogs scroll within themselves.
Ad blockers and privacy extensions do not get in the way. If a feature still does not respond, try a private browser window to rule out an extension.
How to report a bug
From the account menu (top-right corner) pick "Send feedback", then "Report a problem" - ideally on the screen where the bug happened, because a screenshot is attached automatically. Describe what you clicked and what happened. If the message has a "Technical details" link, expand it and copy what it says into the report. We reply to the address you sign in with.
A HeatAlgo report follows EN 12831-1 and EN 1264, not ACCA Manual J, and is not accepted for permits or rebates.