You have a Perfect Moose Jack using its own boiler to provide steam.
It seems there is something wrong with the heating phase of the water or there might be water missing in the boiler.
Turn the device off, wait a few seconds, and turn it on again (little black button at the back of your device).
Still struggling after switching the device off/on?
Contact your local moose dealer.
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The following message appears on screen:
WHY DOES THIS ERROR POP-UP AFTER INSTALLING A PERFECT MOOSE JACK?
If the boiler is empty when switching on a Jack, then it is likely that it doesn't fill up and warm up completely within in the timeframe for this error code.
Turn the device off, double check the water inlet connection, and turn the device on again.
Contact your local moose dealer if the problem persists.