All you need to know about the heat wave can be found on the national weather map. From the Deep South all the way up into New England and the upper Great Lakes region, temperatures have been sweltering in the 90s and higher.

Cities like Billings Mont., Wichita Kan., and Boise Idaho have registered triple-digit temperatures. Adding the humidity factor gives a heat index of 100°F and higher to most of the United States.

Utilities report record demand on their generating capacity — something that attracted the attention of Energy Secretary Bill Richardson, who is pondering some kind of federal intervention to ensure the reliability of the nation’s electric energy supply.

This kind of heat virtually guarantees that unitary shipments will exceed last year’s 6.2 million record level. Year-to-date, shipments are about 10% ahead of last year’s pace.

Supplies steady

Fortunately, hvac contractors (who are understandably too busy to talk) seem to be having little problems getting equipment.

Wholesalers, in fact, uniformly agree that the entire inventory-control process has been improved in recent years, in contrast to the earlier feast-or-famine pattern in which they routinely ran out of product by early August.

Maybe it’s the computers, maybe it’s improved order-entry systems, maybe it’s better forecasting — whatever the reason, they have been able to keep up with the increased demand.

Manufacturers have gotten smarter, too, says Dan Hinchman Jr. of Aireco, with 32 outlets in Maryland and Virginia. “The pipeline is easier to fill.”

He adds, “In the old days, if you ran out of compressors or condensing units in July, your season was over. There was no way you could get product.

“Today it’s very much improved. Even if you have to double your order of unitary products late in the game, chances are you can do it.”

The mid-Atlantic weather has been unusually hot and sustained, he says, in contrast to last year, when most of the heat stayed in the South and Southwest. Hinchman says his company will have a record year.

According to New Jersey wholesaler Jim Luce, of Luce, Schwab & Kase, “We had the best June in the company’s history, up about 20%. And it looks like July will be a second record month.

“We’re in the middle of a draught, and the weather service says we may have ninety-degree temperatures indefinitely.”

A lot of Luce’s volume comes from the commercial air conditioning sector, which reflects New Jersey’s booming nonresidential building activity.

Cleveland wholesaler Vic Farr, of Refrigeration Sales Corp., says the extended heat wave has pushed his year-to-date sales up between 8% and 10%, counterbalancing last year’s “no-show” winter.

The Carrier wholesaler notes that the surge has affected both parts-and-pieces and equipment equally. He has also noted a change in the pattern of compressor sales — slightly downward. He attributes this to the practice of selling a complete replacement of the condensing unit, even in relatively “young” systems that are not even 10 years old.

Hot all over

Last week in city after city, newspapers and TV stations led with the heat wave. Here’s a sampling from local newspaper reports.

Atlanta: Air conditioning problems kept 215 state employees out of their offices. Employees were told to work at home or at other office locations.

Naturally, air conditioning technicians are working overtime, and their dispatchers have to pacify irate customers. “The heat swells their brain cells,” says Maureen McDowell, of Cobb Heating & Air Conditioning.

Boston: Needham Oil and Air is booked through August for installation of central air conditioners, and September is quickly filling up. Even Needham staffer Rosemary Marshall, who has survived until now without central cooling, had a system installed.

“If you don’t have to be hot, then why be hot,” she asked. “Life is too short.”

Window air conditioners are as rare as rubies. Just ask Harrison Supply, where customers are buying the units right off the truck.

Cincinnati: Here, where at least 11 heat-related deaths were reported, municipal officials hope the city’s cooling centers will alleviate some of the pain of 19 days in the 90s.

Detroit: A “ring of fire” — a series of unstable weather with high winds and power outages — surrounded the area. In addition to trees being uprooted, many residents had to suffer through a no-cooling period until power was restored.

The area is on its way to the hottest summer in its history, says the National Weather Service, with an average July temperature of 76.31°. This translates into demand for central cooling, says Joel Wensley, co-owner of Mechanical Heating & Cooling, Dearborn.

His dispatcher hears a lot of comments like this: “I can’t wait any longer, go ahead and install an air conditioner.” Sales are up 20% over last year.

Minneapolis: The Twin Cities charted a 99° day, tying a record that was set in 1941. “Ninety-nine degrees is sort of pressing our tolerance level here,” said Craig Edwards of the National Weather Service office.

In St. Paul, a Sears outlet reported selling between 800 and 1,000 window air conditioners during the past three weeks. Northern States Power has been hitting the switch that cycles air conditioning units off and on at 15-min intervals.

St. Louis: The high reached 102°, making it the hottest day of its 12-day span of 90-plus degree weather.