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The Truma hot water and heating system isn't working

This article will walk you through troubleshooting options to remedy the Truma Hot Water and Heater system

There are many reasons relating to why your Truma Hot Water and Heater system could be displaying a triangle with an exclamation mark and an error code.  Please work through this troubleshooting list to eliminate and solve the fault.  See to the right a photo of what the error code will look like on your control panel:
Error Codes 
An error code should come up on the control panel screen (as pictured above) when there is a problem.  Note down the letters and numbers and refer to your Manuals or this online troubleshooting guide.
517 Error Code
This is one of the most popular Error Code that comes up.  This means your gas supply has been interrupted.  This can be your gas bottle running low or running out so swap over to a new full gas bottle.  This error can also occur when the main control panel is turned off before the Truma control panel is fully turned off and shut down.  Therefore, if you have the heater and hot water running, please ensure you fully turn them off on the Truma control panel – wait a few minutes while it shuts down, then turn off the 12volt on the main control panel.  See below a helpful remedy for this fault.
Remedy fault 507 / 516 / 517 (gas supply interrupted)
• Restore the gas supply, for example by connecting a full gas cylinder.
• Then confirm or delete the fault code by tapping the rotary push button. Please note that the first tap might only activate the backlighting of the control panel.
• The heating then starts automatically if there is a heating requirement.
Note: If fault 507, 516 or 517 is displayed in the heater's control panel, switching the control panel on and off does not help. This does not delete the fault but blocks the heater for 15 minutes. The heater is also blocked for 15 minutes if fault 507, 516 or 517 is deleted four times without the gas supply being established.
Remedying flashing fault 507 / 516 / 517 (gas supply interrupted)
The fault code 507, 516 or 517 flashes because the heater is still in a 15-minute blocking time. This was possibly caused by the heater control panel being switched off or because the heater's 12-Volt supply was interrupted. The heater is also blocked for 15 minutes if the displayed fault is deleted four times without the gas supply being restored.
• Wait out the 15-minute blocking time for the heater. During this time, do not switch off the heater's control panel and also do not interrupt the power supply.
• As soon as the heater's blocking time has expired, the fault is then displayed permanently rather than flashing. It can now be deleted as described in the point above.
Here are some other things to check:
A window is open (Model Specific)  
• Check the window with the Truma safety switch on it is closed (this will not relate to all models) - see below a photo of what the switch looks like:
The gas bottle is empty  
• If you are running your heater or hot water from the Gas source, check your Gas bottle to ensure it’s not empty or running low and/or change to your spare full bottle.  Ensure the regulator on the gas bottle is fully open.  Your heater and your hot water need more gas pressure than your oven or hobs.
Control panel  
• Ensure you have selected the correct source on the Control Panel.   
• To learn more about working your control panel please refer to our article on how to work my control panel or view the video below.
Mains source 
• If you are running your hot water and heater from the Mains source, check that power is coming into your motorhome.  You can do this by seeing if your microwave is going, or mains element on your oven hob.  Also, check your Mains RCD fuses to ensure you haven’t tripped.  The RCD fuses should be in the up position.
Last Resort – Final Truma System Reset
If all the above has been checked and followed and the error code still will not clear, you can do a full reset on the Truma unit itself.
See below Instructions:
Important Safety Note:    Ensure you are not plugged into Mains when removing the cover 
• You will find the Truma unit underneath one of the seating areas 
• Remove the cover from the unit once you have located it 
Make sure you remove your 240-volt connection if plugged into mains! 
• Locate the long brown button 
• Push it in (very gently) and hold it down until you see an orange LED light up
• Remove your finger the replace the cover
• Please note:  You may need to repeat the process up to 3 times. 
If you continue to have error codes after these re-sets, please contact our TrailLite Service Centre.