Napoleon Gas Fireplace: Oil-canning (popping/banging metal noise)
Oil-canning (popping/banging metal noise) on a Napoleon gas fireplace: Metal pops or bangs as it heats/cools. The sooner after ignition it happens, the closer it is to the heat source.
Applies to: Napoleon gas fireplaces - direct vent, natural vent and vent-free (general service manual)
Common causes of oil-canning (popping/banging metal noise)
- Loose screws/panels/baffle in firebox
- Vent not supported
- Vent collar stressed
- Burrs at screws behind upper louvres
- Unsealed 7" vent (cold days)
- Compressed venting (top vent)
How to fix oil-canning (popping/banging metal noise): step by step
- Early after ignition: check the firebox heat shield, log support and baffle for loose or stripped screws; tighten or replace.
- Late after ignition: support the vent pipe every three feet.
- Relieve stress on the vent collar by adjusting the venting.
- Check screws behind the upper louvres on the zero-clearance shell for burrs/tears; file smooth.
- Worse on cold days: seal the 7" vent pipe and area around it.
- Top vent units: make sure the venting did not compress when the unit was slid into place.
If the unit shows an error code, look it up: Napoleon Gas Fireplace codes
Models
Source: Napoleon (Wolf Steel) Service Manual W415-0118, Part 4 Other Issues, Oil-Canning Flowchart, p.28. Written in our own words as a summary; always check the original manual.
General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.