By Mike LaCrosse

NATICK (CBS) – HVAC companies are busy keeping up with calls from customers.

Doug Woodacre has seen his share of heat waves as a third-generation owner of Woodacre Residential Heating and Cooling in Natick.

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That’s why he’s not surprised his team gets busy when the temperatures rise, and some of those calls can be pretty grueling for his crews.

“Our attics are 110, 120 degrees. We have to go up there and work. The sweats pouring down. You have glasses on; you can’t see. Yeah, it’s tough,” said Woodacre.

Kids in Natick stay cool with popsicles. (WBZ-TV)

For those without central AC, it was off to the hardware store for a window or portable unit.

“They’re disappearing off the shelves like very quickly,” said Angel Davis.

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On days like Tuesday, you need to pay attention to heat stroke and heat exhaustion. Early signs of both include headache, dizziness and fainting.

There are some key differences between heat stroke and heat exhaustion. Check your skin. If it’s hot, red and dry, it could be heat stroke.
If it’s cold, pale and clammy, it could be heat exhaustion.

Check your pulse as well. If it’s fast and strong, you could have heat stroke. If it’s weak, it could be heat exhaustion.

(WBZ-TV graphic)

“When you get to that point where there is confusion or passing out or severe headache or that temperature being elevated, we get very concerned for heat stroke and that really needs to be evaluated quickly,” said Amelia Nadler of PhysicianOne.

At Cochituate State Park, there were plenty of people staying hydrated, protecting themselves from the sun and cooling off in the water.

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“It’s very cool. It felt really refreshing,” said Dawn McCormick.