I did find a small gas leak at a joint near the control valve of the furnace. It seems to be dry joint compound causing it. Took the joint apart and re-did using yellow Teflon tape.
This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.