Anthony — TSSA-Certified G1 Gas Technician
TSSA G1 licence #TBD · 15+ years in gas and mechanical trades · Service area: Greater Toronto Area, Ontario
Last updated: 2026-08-03
What does a red tag clearance visit actually involve?
Clearance starts with confirming exactly what the tag identifies as the defect, not with assuming the appliance needs replacing. The technician reviews the tag, the appliance data plate, and any notes left by the gas utility or fire department, then physically inspects the appliance, the venting, and the mechanical room's combustion air supply before touching anything.
Once the defect is confirmed, the correction itself — whether that's restoring a combustion air opening, relining a chimney, replacing a gas valve, or correcting a vent clearance issue — is completed and then tested. The tag is not cleared based on the repair alone; it's cleared once the tests below confirm the appliance is operating safely.
What gets verified before a tag is cleared?
Three tests are standard on nearly every clearance, and a technician will not sign off without them regardless of how routine the repair looked.
Combustion analysis measures the flue gas composition — carbon monoxide, oxygen, and combustion efficiency — to confirm the burner is operating within a safe range after the correction. A spillage test checks whether flue gas is escaping into the living space rather than exhausting outdoors, and it's done under worst-case depressurization: exhaust fans, a clothes dryer, and any other competing exhaust equipment running simultaneously, since this is the condition most likely to reveal a marginal chimney or combustion air problem that would pass under quiet conditions. A gas pressure and leak test confirms the supply pressure is within the appliance manufacturer's specification and that no piping disturbed during the repair is leaking.
How long does a red tag clearance in Toronto typically take?
Timelines split into three rough categories. A defect that can be corrected with materials a technician carries on the truck — a missing shut-off valve, a restored combustion air opening, a drip leg — is usually cleared in a single visit, often within a few hours of arrival.
A defect requiring a part that isn't stocked, such as a specific gas valve or control board, typically adds a return visit once the part arrives, which can range from a day to a week or more depending on availability. Structural corrections — chimney relining, a change from atmospheric to power venting, or a gas line resizing — take the longest, since they involve more labour and sometimes permits, and are usually scheduled rather than completed on the initial call.
What happens when the meter itself is locked?
There is an important distinction between an appliance being shut off at its own valve and the gas utility locking the meter for the whole property. If only the appliance was isolated, the technician who clears the tag can restore gas to that appliance directly once the correction is verified.
If the utility locked the meter — which happens in cases involving a suspected leak, an uncontrolled hazard, or non-payment overlapping with a safety issue — the meter has to be unlocked by the utility itself, not by the technician who did the repair. In that situation, the technician's documentation that the defect is corrected is what the utility typically requires before they'll re-attend to unlock the meter, so getting that paperwork issued promptly matters for how quickly service is restored.
Why does sending photos before the visit matter?
Toronto's mix of century homes, converted multiplexes, and condo mechanical rooms means the same red tag wording can point to very different underlying causes depending on the property. Photos of the tag itself, the appliance data plate, the vent termination or chimney connection, and the general mechanical room area let a technician form a working diagnosis before arriving.
This matters most when parts might be needed — if a technician can identify from photos that a specific control board or valve is the likely culprit, that part can be brought on the first visit instead of discovered as missing once the truck is already on site, which is often the difference between a same-day clearance and a two-visit repair.
What documentation do I get once the tag is cleared?
Once the appliance passes its post-repair tests, you receive documentation confirming the defect, the correction made, and the test results, which serves as your record that the tag was cleared and by whom. Keep this for insurance purposes, and for resale if the property changes hands, since a buyer's inspector or lawyer may ask for evidence that a prior red tag was properly resolved rather than simply worked around.
Frequently asked questions
Can any plumber or HVAC technician clear a red tag in Toronto?
No. Clearing a red tag requires a TSSA-certified gas technician holding the correct licence class for the appliance's input rating — a G2 for smaller residential equipment or a G1 for any size of gas appliance, including commercial equipment.
Does clearing a red tag always mean replacing the appliance?
No. Many red tags in Toronto trace back to venting, combustion air, or gas pressure issues that are corrected without replacing the appliance itself. Replacement is generally only required for a confirmed cracked heat exchanger or when parts for an older unit are no longer available.
What if the tag doesn't clearly say what the defect is?
The tag itself is often brief, so the technician's on-site diagnosis is what actually identifies the underlying cause. Sending photos of the tag and mechanical room ahead of time still helps narrow down likely causes before the visit.
Will I be without heat or hot water the whole time?
Only if the tag is a Type A, which shuts off the appliance immediately. A Type B tag leaves the appliance running with a correction deadline, so heat and hot water continue while the repair is arranged.
Do I need to be present for the whole clearance visit?
You need to provide access to the mechanical room and be reachable for questions, but you don't need to be present for every test. Many clearances in occupied homes are completed while residents go about their day.