Southwest Gas Red-Tagged Your Furnace? What Form 106.0 Means in Las Vegas

Short answer: Southwest Gas left a Notice of Hazardous Conditions on Customer's Premises (Form 106.0) after a limited courtesy safety inspection found a problem on gas piping or an appliance. Affected appliances and gas valves were left off for safety. Do not remove the notice, do not turn the gas valve back on, and do not try to relight the furnace. Hire a licensed plumber or contractor to correct what the form lists, pull any permit the notice or your city or county requires, then call Southwest Gas at 877-860-6020 so only Southwest Gas or its contractors reinstate service.

If you smell gas at any point, leave and call Southwest Gas or 911 from outside.

What the notice actually is

Many Las Vegas-area homeowners call this paperwork a red tag. Southwest Gas's official title is Notice of Hazardous Conditions on Customer's Premises (Form 106.0). The current form revision is marked Form 106.0 (12/2025).

On the front of the form, a Southwest Gas technician records:

• whether the meter was left on or off
• which appliance is involved (Heating is one of the checkboxes, along with water heater, range, dryer, gas piping, and others)
• which hazardous conditions were identified, from a numbered list
• whether the condition is flagged as a fire hazard, explosion hazard, and/or poisonous carbon monoxide gas hazard
• whether a permit and inspection from the local building and safety department are required before gas service will be reinstated
• the instruction to contact Southwest Gas at 877-860-6020 when the condition is corrected

The form states that the visit was a limited courtesy safety inspection of the gas piping and appliances, not a full inspection of every gas component in the home.

What not to do after Form 106.0

Southwest Gas's warning on Form 106.0 is direct: corrective work must be done by a licensed plumber or contractor. Do not attempt the work yourself. If corrective work is done improperly, or if appliances or gas valves are turned on before the hazard is fixed, the form warns of fire, explosion, or a buildup of poisonous carbon monoxide gas.

In practical terms for a furnace:

• Leave the notice in place. Do not peel it off or throw it away.
• Do not reopen the appliance shutoff valve or the meter yourself.
• Do not relight the furnace or bypass the tag with a temporary connector.
• Turn the system off at the furnace switch or system control if it is still calling for heat.
• Keep the tagged heating appliance off until a licensed contractor finishes the correction and Southwest Gas reinstates service when that step applies.

Southwest Gas also states that only Southwest Gas and Southwest Gas contractors are authorized to reinstate service.

Hazardous conditions that often involve a furnace

Form 106.0 lists twelve condition codes. Several map directly to heating equipment and its venting:

1. Vent system improperly installed
2. Vent restricted
3. Combustibles too close to vent with signs of heat damage
4. Possible cracked heat exchanger
5. Flue restricted
6. Circulating air not sealed airtight from combustion air
7. No combustion air
8. Insufficient combustion air causing operational problems
9. Improper burner combustion
10. No Temperature Pressure Relief (TPR) valve (more often a water heater item)
11. A measured cubic-foot-per-hour leak in the piping system
12. See Comments

A Las Vegas furnace often sits idle through a long cooling season, then gets asked to run on the first cold night. Venting, combustion air, burner combustion, and heat-exchanger concerns are exactly the kinds of heating-side items Form 106.0 is built to capture when a Southwest Gas technician finds them during a courtesy safety check.

If the form marks a possible cracked heat exchanger, treat that as a stop-use condition until a licensed HVAC contractor evaluates the furnace. Some exchangers can be repaired under the manufacturer's rules; others end in furnace replacement. That decision belongs to the licensed contractor after they see the unit, not to a homeowner guess.

If the form marks a carbon monoxide hazard, or anyone has flu-like symptoms with a gas appliance in the house, also read our guide to carbon monoxide and your furnace. Carbon monoxide has no smell of its own.

Gas smell is a different emergency

A Form 106.0 notice is paperwork left after Southwest Gas already found and shut down a hazard. A live gas odor is a separate emergency.

Leave and call Southwest Gas or 911 from outside. Do not flip switches, touch appliance controls, or use a garage door opener on the way out. Southwest Gas's safety pages say to evacuate, leave doors open, and call 911 and Southwest Gas at 877-860-6020 from a safe place, day or night. For the full local walk-through of gas odor versus other furnace smells, see furnace smells like gas.

How to get the furnace corrected

1. Read the form. Note which appliance box is checked, which condition numbers are marked, whether the meter is on or off, and whether the permit checkbox is marked.
2. Call a licensed plumber or contractor. Form 106.0 says to engage licensed help and points customers to Southwest Gas Energy Specialists at 800-654-2765 or swgas.com for a listing of licensed plumbers and contractors. A Nevada-licensed HVAC contractor is the right call when the tagged appliance is the furnace or heating system.
3. Fix only what the notice requires, then verify the rest of the system as needed. The form's reverse side says the courtesy inspection applies only to the hazardous conditions noted and does not mean the home has no other hazards or defects. Southwest Gas recommends a thorough inspection of all gas appliances and components by a licensed plumber or contractor.
4. Pull any required permit. If Form 106.0 checks the permit box, a permit and inspection from the appropriate building and safety department are required before gas service will be reinstated.
5. Call Southwest Gas to reinstate. When the condition is corrected (and any required local inspection is clear), contact Southwest Gas at 877-860-6020. Do not restore gas yourself.

Permits in the Las Vegas Valley

Which office issues the permit depends on where the house sits, not only on a "Las Vegas" mailing address. Unincorporated Clark County covers large areas such as Enterprise, Spring Valley, and Paradise. The City of Las Vegas, City of Henderson, and City of North Las Vegas each have their own building departments. Manufactured and mobile homes go through the Nevada Manufactured Housing Division instead.

In unincorporated Clark County, Building & Fire Prevention lists Simple Online Permits that often come up after a gas shutoff or furnace change:

• Gas Re-Tag under Plumbing (residential and commercial), one item per permit
• Furnace Replacement under Mechanical (residential), sized under or over 100K Btuh, one appliance per permit
• A/C Furnace Replacement under Mechanical when both pieces change

Clark County also notes that Simple Online Permits are not renewable once expired, and that appliances inside or attached to a manufactured home need Nevada State Manufactured Housing Division permitting instead.

When Form 106.0 says a local permit and inspection are required, ask your licensed contractor which permit matches the correction: a Gas Re-Tag for piping or tag clearance, a furnace replacement permit when the heater is being changed out, or another mechanical or plumbing permit for the exact scope. For the broader permit map across Clark County and the three cities, see HVAC permits in Las Vegas.

After the repair: reinstatement and your rights

Form 106.0's reinstatement line is specific: when the condition is corrected, contact Southwest Gas at 877-860-6020. Only Southwest Gas and Southwest Gas contractors are authorized to reinstate service.

The reverse of the form also notes that Southwest Gas may refuse or discontinue gas service under its rules on file with the state commission, and that the notice covers only the hazardous conditions listed.

If you disagree with the utility's decision, Form 106.0 lists a consumer appeal path to the state commission Consumer Affairs Department. For Southern Nevada, the number printed on the form is 702-486-2600. Northern Nevada is listed as 775-684-6100.

What a Colton visit covers after a tag

When the tagged appliance is the furnace, a Colton technician can diagnose the listed condition, explain repair versus replace options when that question comes up, and coordinate the mechanical side of a permitted correction. Gas-meter locks and final utility reinstatement stay with Southwest Gas.

For heating service details, see heating repair.

Open 24 hours, 7 days. Book online or call (702) 738-6976 to schedule. For after-hours heating help, see emergency heating repair.

Frequently asked questions

What does a Southwest Gas red tag on a furnace mean?

It usually means you received Form 106.0, the Notice of Hazardous Conditions on Customer's Premises. A Southwest Gas technician found a hazardous condition on the heating appliance or related gas piping or venting, left the affected appliance or gas valve off, and documented the condition codes and hazard types on the form.

Can I take the tag off and turn the furnace back on?

No. Form 106.0 warns against turning appliances or gas valves back on before the hazard is corrected by a licensed plumber or contractor. Only Southwest Gas and Southwest Gas contractors are authorized to reinstate service after the form's reinstatement step.

Do I need a permit after a Southwest Gas hazardous-conditions notice?

Sometimes. Form 106.0 has a checkbox that says a permit and inspection from the appropriate building and safety department are required before gas service will be reinstated. When that box is marked, your licensed contractor should pull the permit for the jurisdiction that covers the house. In unincorporated Clark County, Gas Re-Tag and furnace replacement are among the Simple Online Permit types.

Who turns the gas back on?

Southwest Gas. The form tells you to call 877-860-6020 when the condition is corrected, and it states that only Southwest Gas and Southwest Gas contractors may reinstate service.

What if I smell gas after the furnace was tagged?

Leave and call Southwest Gas or 911 from outside. A tag means a hazard was already found and shut down; a new or ongoing gas odor is still an emergency and needs the utility and emergency responders, not a homeowner restart.

Can I appeal Southwest Gas's decision?

Yes. Form 106.0 states you have the right to appeal the utility's decision to your state commission Consumer Affairs Department. Southern Nevada is listed on the form at 702-486-2600.