How to Maintain a Velit Gas or Diesel Air Heater

These heaters are generally maintenance free but there are a few things to keep in mind to ensure reliable performance from the heater. 

Run the heater on manual mode high for 20+ minutes every month or two, even over the summer months. 

The idea is to pull fresh fuel into the lines even in those months during the year that the heater is not in use (warmer weather). 

You want to avoid not running the heater for the summer then when attempting to start in the fall winter, jamming a bunch of bad fuel through the heater. 

Pulling fresh fuel through the system also lubricates the fuel pump.

Summer is also a great time to inspect and replace fuel lines that show signs of being weathered. Possible fuel filter replacement.

Lastly, in general, you want to allow the heater to run on manual mode high, as this is how the heater cleans itself.