Every hour of every day last week, Frank Rich checked the pulse of his business.

From the hourly sales reports he could usually tell by midday whether the four Rich's shoe stores and Georgetown "Gamineri" would beat last year's numbers.

By Thursday noon the Connecticut Avenue store had done better than 50 per cent of last year's business for that day and still had a strong evening ahead. The others were close to the pace - even Georgetown, where the nights were dead. It would be a good day, he knew, and the season was finally looking better.

It was that kind of a Christmas for most retailers.

Fall business was solid, but rarely spectacular, with November chain store sales 9 to 15 per cent ahead of 1976. Predictions of a record year made many retailers nervous.

After Thanksgiving the momentum didn't seem to pick up much. There was too much snow for people to shop in some parts of the country and not enough for them in others, merchants complained over their Maalox and martinis.

The Monday before Christmas the season was summed up by Sears Roebuck & Co. chairman Arthur M. Woods: Sales were running 10 per cent ahead of last year's very strong figures. A record year, to be sure, yet not that great considering Sears sales for the first 11 months were 15.9 per cent better than in 1976.

But three days later Sears public relations people were back on the telephones with new numbers. Sales are up 14 per cent, the nation's biggest retailer reported, a surge that signified millions of dollars of late Christmas buying.

The final figures still aren't in; after-Christmas sales are as much a part of the season as the Christmas Eve crunch. This year there was a bonus - the final shopping day was Saturday, the best day of the week.

Nationally, Sears' 14 per cent sales gain is probably the best index available of total retail spending. Local merchants willing to mention numbers talk in the 8-to-20 per cent range, in terms of volume in excess of 1976 levels.

In Washington area, and many other parts of the country, there are many merchants competing for the Christmas business. "I sense from top management the feeling that the pie is being split into many more sections," said Leonard Kolodny, retail director for the Metropolitan Washington Board of Trade.

Kolodny said more stores mean that "though people are spending more money this year than last, the gains are not as high as anticipated for many stores."

An important reason why Washington business this year was better than last is politics, said Kolodny and many merchants. Elections and inaugurations aren't good for business, retailers say, but this year was politically placid.

Business in downtown Washington benefited not only from the added access via Metro this year, but also from removal of subway construction from the streets, said Kolodny. That view was repeatedly by Simon Atlas, who runs the local operations of Herman's World of Sporting Goods, and William D. McDonald Jr., vice president for sales promotion of Woodward & Lothrop.

"This was the first year in five years that our downtown store did better than the previous year," said Atlas, crediting improved access to the downtown shopping district.

Calling Christmas sales "outstanding," Atlas said Herman's volume was up 15 to 20 per cent. Outdoor sportswear was exceptionally strong, especially running clothes, shoes, shorts and warmup suits.

Woodward & Lothrop also benefited from transportation improvements downtown, said McDonald. Traffic through the Metro station entrance to the basement of the main store was up 40 per cent over last year, and sales were ahead almost moved into Woodies "Underground" shops in the former bargain basement.

Women's apparel generally was good for Woodies, he said, with soft looks and pastel colors the best sellers. Star Wars bedsheets were so hot they sold out the first time they were advertised.

Woodies won't talk in numbers, but McDonald said the chain was "keeping up with last year" and "doing nicely."

Hecht Co. President Allan Bloostein said, "It's been a very strong Christmas, reflecting consumer confidence." Downtown business has been better the last couple of months, he added, but Hecht's strength is in the suburbs.

Bloostein noted that the sales boom was unusual this year because there was "the same kind of response in the Baltimore area . . . no edge to Washington as had been true in the past."

"It's a quality Christmas," he added. "Better things are selling, such as tape recorders, television games. Quality lines are paying off."

David Ritz, vice president of Ritz Camera, said high ticket items - single lens cameras, sound movie cameras - were boosting sales. "We're up from a year ago, very well up," said Ritz.

At corporate headquarters of Garfinckel, Brooks Brother, MIller & Rhoads, sales were "ahead of plan and ahead of last year," said Robert Vandemark, executive vice president for finance and operations.Vandemark said he was seeing sales figures that ran 8 to 15 per cent ahead of the same period last year. "It's pretty much across the company. It's impressive in that."

Not all stores found their business gains based so broadly. Edith Schubert said sales of food processors at her China Closet stores were astronomical. "We've never had anything go like this," she said. Cuisinarts and copies of them were selling like crazy, "but that's the only thing that's selling," she added, saying other business was only so-so.

The strength in big ticket sales and the 6 per cent inflation over last year tended to exaggerate one retail problem - the failure of unit sales to keep pace with dollar volume. With rare exceptions, Washington merchants say they are selling goods, but getting more money for them.