Make a decision
Registered gas contractor versus duct cleaner
One scope
Ontario fuel-appliance service requires the correct TSSA contractor and technician status.
The other scope
A duct-cleaning contractor may specialize in duct assessment and source removal.
A concrete example
A duct crew can clean a return while a gas technician assesses burner and venting. If one bid includes both, ask who does each part and verify the Ontario fuel-work credentials.
Which question settles it?
Verify qualifications for each work item; one crew's duct tools do not authorize gas adjustments.