YOKOTA AIR BASE, Japan — The air conditioning has been flipped on in most Yokota facilities and full activation was scheduled to be completed by Friday, just in time for Memorial Day and the unofficial start of summer.

The changeover to cooling season follows a brief period of no heat or air in Yokota’s buildings — part of an annual strategy that saves the base about $5,000 a day, according to Master Sgt. Randy Stoker, the 374th Civil Engineer Squadron’s mechanical section chief.

It means workers and residents go without either for roughly a month during the transition each spring and fall.

“We inform people living on base of this program every year before it starts,” he said.

“While there may be some times during this period where people might feel uncomfortable, this program is enormously cost-efficient.”

The last centralized heating unit was shut down on base April 24, he said.

Air conditioning is turned on in phases, with mission-critical buildings given top priority followed by high-use or poorly ventilated facilities and then all others.

Each has a different threshold for determining a startup date, Stoker said:

Buildings such as the hospital and facilities with equipment that must be maintained at controlled temperatures are cooled regardless of outside weather conditions, based entirely on mission needs.

Cooling of common areas — including the Yokota Community Center, Samurai Café dining facility, schools and clubs — won’t begin until at least two weeks after heating season ends.

In addition, there has to be a five-day average high temperature of 72 degrees or higher between 11 a.m. and 4 p.m.

The two-week buffer zone between heating and cooling season also applies to lower-priority facilities such as family housing and bachelors quarters, where the air conditioning doesn’t get triggered until the weather averages highs of at least 74 degrees from 11 a.m. to 4 p.m. over a five-day stretch.

Capt. Robert P. Rose, the 374th Civil Engineer Squadron’s maintenance engineering chief, said Yokota spent about $5.8 million last year in heating and cooling costs over an 11-month span.

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