Paola Pedroza Reynoso and Alejandro Jimenez Ramirez at Los Molcajetes prep food in Fairfield on Tuesday during a heat wave.

When it’s hot outside, it’s even hotter inside food trucks.

As a heat wave hit the Bay Area on Tuesday, Victor Jimenez was working aboard the Los Molcajetes Mexican food truck in Fairfield. Midday, it was 101 degrees. And the fan broke.

“We’ve had heat strokes and dizziness,” Jimenez said. ”We have to hydrate constantly, and sometimes it’s so busy you don’t have time to drink something and you develop a headache.”

Food truck operators deal with a different set of challenges than restaurants, including the greater exposure to high temperatures. Add roaring fryers and burning griddles to a cramped space, and the heat intensifies.

Alejandro Jimenez Ramirez at Los Molcajetes, a Mexican food truck in Fairfield, works amid triple-digit heat.

While the fleet of Filipino-Mexican food trucks Señor Sisig mostly operates in cooler San Francisco, owner Evan Kidera is no stranger to working in the heat.

“It’s challenging,” he said. “We don’t have air conditioning inside the trucks. And a lot of the time, the exhaust fans for the grills are built for smoke, but not really to control temperatures inside the truck.”

The mounting heat also puts a strain on refrigeration, Kidera said. And the desire to dial down sources of heat can influence the day’s menu, said Herman Rodriguez, who operates Mexican food truck La Roca in Walnut Creek, which saw triple-digit heat on Tuesday.

“Even if we have air conditioning, sometimes that doesn’t make a difference when you have the steamer, fryer and griddle on. Sometimes we’d rather not use the fryer,” Rodriguez said.

To cope with high temperatures and avoid any health complications, workers turn to cold water or sports beverages with electrolytes. But taking some time away from the kitchen is also key.

“When we get the chance to step outside, we go,” Jimenez said. “But when it’s time to cook, we work.”

The Taco Panzon operator Martha Barajas has driven her truck around Oakland for 20 years. She says there’s a bit of a mind-over-matter side to dealing with the heat in a mobile kitchen.

“If you keep saying ‘it’s so hot, it’s so hot’ to yourself, it’s not getting any better,” she said, adding that the Taco Panzon is also outfitted with windows and vents to help regulate the temperature.

Colton Foster waits for his food at the Los Molcajetes Mexican food truck in Fairfield.

Outside of the truck, work suspensions to protect workers from the risks of high temperatures also have an impact on business.

“Workers make up over 20% of our sales. When it gets over 93 degrees, the grape harvest is suspended, and we get a lot of those workers during lunch. The roofing and cement workers also don’t work in excessive heat,” Jimenez said.

At La Roca, Rodriguez said he sees fewer customers when it’s hot out because people don’t want to leave their air-conditioned houses. For others, the high temperatures bring a bump in sales.

“Sometimes it’s the opposite. It’s so hot in some people’s houses and apartments that they don’t want to cook and make it hotter,” Barajas said.

The heat is expected to continue Wednesday in the Bay Area. Kidera asks food truck patrons to be patient with workers inside the mobile operations.

“Just be a little understanding about the situation,” he said, “because it's not fun to work in a sauna.”

Mario Cortez (he/him) is a San Francisco Chronicle staff writer. Email: mario.cortez@sfchronicle.com

Mario Cortez joined The Chronicle Food & Wine team in 2022. He is originally from San Diego, where he contributed to local and online publications. He last worked at the Eureka Times-Standard, where he was sports editor and a staff reporter. Cortez was also a regular writer for Eater San Diego.

He likes analog photography, playing soccer and, naturally, great food.