Las Vegas Airbnb AC emergency: what to do when it quits with guests inside

The valley's summer is the baseline, not a heat wave. Across the 1991 to 2020 normals the National Weather Service counts 78.2 days a year at or above 100°F in Las Vegas, 40.5 days at or above 105°F and 9.4 days at or above 110°F, most of them in July and August (NWS Las Vegas, number of days with a specific temperature).

The CDC lists adults 65 and over, infants and young children, people with chronic medical conditions and pregnant guests among those most at risk from heat (CDC, heat and health risk factors). Heat exhaustion shows as headache, nausea, dizziness, weakness, heavy sweating and thirst. Heat stroke shows as confusion, slurred speech, loss of consciousness, seizures, a very high body temperature and skin that is hot and either dry or sweating heavily. Heat stroke means call 911, then cool the person with water and wet cloths while help comes (CDC and NIOSH, heat-related illnesses).

Ask the guest to do these in order and to stop at the first one that is beyond them. Each comes from the manufacturers' own troubleshooting pages (Carrier and Trane troubleshooting pages).

• Thermostat: set to Cool with the fan on Auto and the set point a few degrees below the room temperature. A thermostat left on Heat or on a schedule is the most common false alarm.
• Filter: a grey, clogged filter in the return grille or the indoor unit starves the system of air. Swap it if a spare is in the home; otherwise leave it out for now and say so.
• Breaker: look in the panel for a tripped breaker labelled AC, air handler or furnace. Reset it once. If it trips again straight away, do not try again; that is an electrical fault for a technician (Carrier).
• Outdoor unit: is it running and is the top fan spinning? Trane asks for two feet of clear space around it. A guest can check the disconnect box beside it is switched on, but should not open it.
• Ice: frost on the indoor coil or the copper lines means switch the system off at the thermostat and leave it off. Wait at least 30 minutes for minor ice to melt and call a professional for the rest. Never chip at it (Trane, evaporator coil is frozen).
• Nothing else. Refrigerant, wiring and capacitors are not guest jobs. We never ask a guest to open a unit.

Fans have a limit. The CDC's guidance is to use fans only when the indoor temperature is below 90°F; above that a fan can raise body temperature (CDC, five heat steps factsheet). Its advice for a home without working cooling is cool showers or baths, drinking more water than usual without waiting for thirst and spending a few hours somewhere cool such as a mall or a library (CDC, heat and people with low income). Clark County opens daytime cooling stations in community centres, libraries and senior centres when the National Weather Service issues an excessive heat warning; 2-1-1 has the locations (Clark County news release).

So the message while a technician is found is practical: blinds closed on the sun side, doors to the hottest rooms shut, fans only while the house is under 90°F, water on a schedule and an afternoon somewhere cool on us. A portable air conditioner bought the same day and vented through a window can keep one bedroom liveable overnight. Ask every hour how everyone is doing, by name. A guest who sounds confused or stops replying is the signal to call them, then 911 if you cannot reach them.

Our call order is the host's own HVAC company first, because it already has the unit's model and history. Then the companies in the valley that advertise 24-hour emergency service. Then the contractors the host has used who can at least diagnose. On each call we give the area, the symptom in one sentence (no cold air, running but not cooling, tripping the breaker, iced up) and the fact that guests are in the home now. We ask the earliest a technician can arrive, the diagnostic fee with the after-hours rate and whether the truck carries common parts so the first visit can be the repair.

We send the host the quotes with arrival times and book only on the host's YES. The technician gets the guest's phone number for access; the guest gets the technician's name and window. If a part has to be ordered, get the part name and the earliest date in writing.

The first message goes out before the first vendor call. Every update after it carries a time, a next step and a check on how people are feeling. Replace the parts in curly brackets.

Decide by early evening, not at bedtime. Move the guests if no technician can come today, if the repair needs a part that won't arrive tomorrow or if the house is still above 90°F with the sun going down. Anyone in the at-risk groups moves sooner. Offer a hotel or a comparable listing for the affected nights at your cost, say in writing whether the rest of the stay is still theirs and help with the booking.

A partial refund fits a few hours of discomfort with a same-day fix: a night's rate or the share of the stay they lost. A full refund for the affected nights fits a guest who had to leave. Send it before the guest asks. Under Airbnb's Rebooking and Refund Policy a home that is not habitable at check-in is a reservation issue, with the refund or rebooking cost taken from the host's payout (Airbnb Help Center).

Most of our summer AC calls trace back to a filter or a unit that went into the season untested. The habits that cut them:

• Book a professional inspection every spring, before the first 100°F day, as the US Department of Energy recommends (consumer guide to home heating and cooling).
• Change the filter monthly through the peak season (the Department of Energy's figure for heavy use; Trane says every one to three months). Keep a labelled spare in the home so a guest can swap it.
• Keep two feet clear around the outdoor unit. Have the cleaner check it on every turnover.
• Put a thermostat with remote access in every home and set an alert for indoor temperatures above the mid 80s, so you hear about a failing unit before the guest does.
• Write the thermostat, filter and breaker checks into the house manual with photos. Put the 911 rule above them.