Velit Heater Error 01/Error 02/ Smoke
If your Velit air heater is showing Error 01 or Error 02, having difficulty starting, or producing white smoke, the issue is most commonly related to fuel delivery. In many cases, the heater itself does not need to be replaced. Start by checking the fuel supply and installation before performing additional troubleshooting.
1. Check Fuel Delivery First
The first thing to check is whether the heater is receiving a continuous supply of fuel.
While the heater is attempting to start or running, get underneath the vehicle and visually inspect the fuel line.
You should be able to see fuel moving continuously toward the heater.
What to Look For
- Small bubbles are generally OK.
- Air bubbles or gaps larger than approximately 1/2 inch can cause the heater to operate improperly or fail to ignite.
- Fuel should move consistently through the line while the heater is operating.
- Check for anything in the fuel-line installation that could interrupt or restrict fuel delivery.
If your fuel line is covered with wire loom or protective sleeving, remove at least 2 inches of loom on both sides of the fuel pump.
It is important to leave these sections visible so you can inspect the actual fuel flow and identify excessive air bubbles.
Before proceeding, review the fuel system requirements in our installation checklist:
Velit Air Heater Installation Checklist
2. Error 01 During Initial Installation
During a new installation, the heater may initially display Error 01 simply because fuel has not yet traveled all the way from the tank to the heater.
This does not necessarily indicate a problem with the heater.
If you can see fuel progressing through the line:
- Allow the startup attempt to finish.
- Pull the heater fuse to reset the system.
- Reinstall the fuse.
- Attempt to start the heater again.
It may take a second or third startup attempt before fuel reaches the heater and the heater successfully ignites.
3. Be Very Careful With the Prime Feature
Do not repeatedly use the Prime feature simply because the heater does not ignite on the first attempt.
The Prime feature manually moves fuel toward the heater. Using it excessively can send too much fuel into the combustion chamber.
Over-priming can flood the heater.
A flooded heater may:
- Produce significant white smoke
- Have difficulty igniting
- Fail to start
- Require cleaning before it will operate normally again
If fuel is already reaching the heater, avoid continuing to prime it.
For a new installation, it is generally better to confirm that fuel is moving through the line and allow the heater another startup attempt rather than repeatedly using the Prime feature.
4. What Causes White Smoke?
White smoke is typically associated with excess fuel remaining in the combustion chamber or soot buildup inside the heater.
This can happen after:
- Excessive use of the Prime feature
- Failed ignition attempts
- Improper or inconsistent fuel delivery
- Fuel-line installation problems
- Soot buildup over time
If the heater can ignite and remain running, operate it on High for approximately 15 minutes.
In many cases, the heater will burn off the excess fuel or buildup and the white smoke will clear.
5. If the White Smoke Does Not Clear
If the heater continues producing white smoke, cannot stay running, or will not ignite properly, follow our heater cleaning/back-flushing procedure:
How to Clean a Velit Gas or Diesel Air Heater
Cleaning or back-flushing can remove excess fuel and soot buildup and will often get the heater running properly again.
Important: Cleaning May Only Fix the Immediate Problem
Cleaning the heater does not correct the underlying cause of the buildup.
If the heater became clogged or started smoking because of improper fuel delivery or an incorrect fuel-line setup, cleaning may get the heater running again, but the same problem is likely to return if the fuel system is not corrected.
If you did not accidentally over-prime the heater, it is especially important to inspect the fuel-line installation and determine why the heater developed the problem.
6. Correct the Fuel-Line Setup to Prevent the Problem From Returning
After cleaning the heater, always verify the fuel-line installation before returning the heater to normal use.
Follow our installation checklist carefully:
Velit Air Heater Installation Checklist
Pay particular attention to the fuel supply and fuel-line setup.
While the heater is running, verify that:
- Fuel flows continuously toward the heater.
- There are no large air gaps in the fuel line.
- Small bubbles are acceptable, but bubbles or gaps larger than approximately 1/2 inch should not be present.
- The fuel-line and fuel-pump installation follow the recommendations in the checklist.
- There is no obvious restriction or interruption in fuel delivery.
- At least 2 inches of visible fuel line are exposed on both sides of the fuel pump if the rest of the line is covered with loom.
These heaters are sensitive to proper installation and fuel delivery. An installation may appear to work initially even when one or more installation recommendations are not being followed, but problems can develop later as soot and unburned fuel accumulate.
If the underlying fuel-delivery problem is not corrected, repeated cleaning is only a temporary solution. The white smoke, failed ignition, or Error 01 / Error 02 condition may occur again.
7. Error 01 / Error 02 Troubleshooting
For a complete walkthrough of Error 01 and Error 02 troubleshooting, follow our systematic troubleshooting video:
Error 01 / Error 02 Systematic Troubleshooting Video
You can also reference our complete error-code guide:
8. Still Having Problems? Send Us a Fuel-Flow Video
If you have completed the steps above and still need assistance, please contact Velit Support.
Most Important: Send Us a Video of the Fuel Line
Please send us a short video of the fuel line while the heater is attempting to start or running.
The video should be clear enough for us to see the actual fuel moving through the line.
Whenever possible, show:
- Fuel flowing through the line
- Any bubbles or air gaps
- The fuel line immediately before the fuel pump
- The fuel line immediately after the fuel pump
If loom is covering the fuel line, remove at least 2 inches on each side of the fuel pump before recording the video.
Seeing the actual fuel flow can help our support team identify a fuel-delivery problem much faster.
You Can Also Send Photos or Videos of Your Installation
You are welcome to send us photos or videos showing your complete heater installation, especially the fuel tank connection, fuel line, fuel pump, and routing to the heater.
Our support team can review the installation and point out anything that appears incorrect.
However, our recommendations will be based on the same installation requirements contained in our checklist. If we identify an installation problem, we will generally direct you back to the applicable checklist item and ask you to correct it.
For the fastest resolution, please review the checklist yourself first and correct any items that do not meet the recommendations:
Velit Air Heater Installation Checklist
Quick Troubleshooting Summary
Error 01 / heater will not start
→ Check whether fuel is continuously reaching the heater.
New installation and fuel has not reached the heater yet
→ Reset the heater and attempt another startup. It may take two or three attempts.
Large bubbles or air gaps in the fuel line
→ Correct the fuel-line installation using the installation checklist.
Used the Prime feature repeatedly
→ The heater may be flooded.
White smoke but heater still runs
→ Run the heater on High for approximately 15 minutes.
White smoke does not clear or heater will not run
→ Follow the cleaning/back-flushing procedure.
Cleaning fixes the heater but the problem returns
→ The underlying fuel-delivery or fuel-line installation issue has not been corrected. Follow the installation checklist before cleaning the heater again.
Still need assistance
→ Send Velit Support a clear video showing fuel flowing through the fuel line while the heater is attempting to start or running.
Related Resources
Velit Air Heater Installation Checklist
https://help.velitcamping.com/help-articles/velit-air-heater-installation-check-list
How to Clean a Velit Gas or Diesel Air Heater
https://help.velitcamping.com/help-articles/how-to-clean-a-velit-gas-or-diesel-air-heater
Error 01 / Error 02 Systematic Troubleshooting Video
https://youtu.be/Wyjqrzlp1QI?si=lLkBaWikoQO1tzAe
Velit Heater Error Code Guide
https://velitcamping.com/pages/velit-heater-error-code-guide