President Reagan jets off to California.

Vice President Bush flies up to Maine.

And if you're a member of the Universalist National Memorial Church and want to refresh, renew and relax, you. . . .

"You leave me here to have things repaired and close down the whole congregation, that's what you do," said artist Wesley Huyett mournfully, as he directed the painstaking renovation of "this Southern French Gothic dwelling" at 1810 16th St. NW.

Few pastors go so far as Universalist National's William L. Fox and shut down entirely during these last, slow days of summer but many have curtailed services and activities the past few weeks to give everybody some time in the sun.

For those clergy who stay behind, that can make for the most trying time of all.

"I don't have any vacation, but if I did I would probably go to a monastery to rest," said the Rev. Victor Potapov, pastor of St. John the Baptist Russian Orthodox Church on 17th Street NW. Although Potapov works full time at the Voice of America, until recently he was the only pastor of the church, where services are still held in Russian and Old Church Slavonic.

"I took off days to have church services and all of that, and if I really wanted to go away I could call a monastery and ask a priest-monk to come down," he said, "but we're just too big to close down."

"In five years -- this is sad -- I've probably taken five weeks vacation. Isn't that terrible?" said the Rev. George Stallings, pastor of St. Theresa's Roman Catholic Church in Southeast D.C. At 32, Stallings has also pastored St. Theresa's solo for most of the last five years, but was assigned an assistant in December.

Still, "he's had his month off, and I've had about a week," Stallings said. "I'm beginning to get a little worried about myself."

Stay-at-home clergy cite the difficulty of finding substitutes who are able to minister -- visit the sick, perform funerals, etc. -- as well as hold services, though they acknowledge the problem is more acute in rural communities where one-minister congregations are more common.

In the diocese of Raleigh, N.C., where Stallings first worked, he remembered that "you were extremely lucky to get anyone to replace you for two weeks or a month. So either you didn't take a vacation, or took a few days in the middle of the week before services. In some parishes they may not even have weekday mass."

Though replacements are more easily obtained from other churches in this area, some pastors will stay in town to keep services running smoothly while assistants and choirs take a break.

"We give the choir the month of August. They're not obligated to come and they don't practice," explained the Rev. John Mudd, new pastor of Sts. Paul and Augustine Roman Catholic Church. The practice began because the large church at 15th and V streets NW has no air conditioning, so the normally crowded 12:30 mass moves to a smaller chapel. "But attendance really drops off," Mudd said. "We lose people to the air conditioned churches," he said, as well as to those whose choirs go full blast.

For those clergy dreaming of their own time in the sun, there is that needling little feeling in the pit of the stomach telling them, "Don't go, don't go."

"There's this little guilt trip you do about whether you should go or not," said the Rev. Jesse Anderson Jr., vicar of the Chapel of St. Philip the Evangelist in Southeast D.C.

Anderson tries to provide for his absence by calling in "supply clergy" from the denomination, or by switching the Sunday service to morning prayer led by an assistant. Despite these precautions, Anderson has postponed his vacation twice this summer. "You always get the joshing from the congregation, 'What do you mean vacation, you only work one day a week,' and like that," he said.

"But you're always saying, 'What if, what if,'" added Anderson. "Believe me, vacations are among the most stressful times for clergymen. But you have to get refreshed or you're cheating the parishioners."

Of course, a number of clergy are able to keep services in full swing despite the summer heat and lure of the outdoors. "We're lucky enough to have two pastors, a choirmaster and an organist," said the Rev. Raymond Shaheen, pastor of St. Luke Lutheran Church in Silver Spring. "We maintain a full schedule year round. Yes, we firmly believe that our congregation deserves a quality experience throughout the summer months. We'll be here year 'round, come wind or come weather, we'll be here."

At the otherend of the spectrum is Universalist National, where even the letter "e" appears to be on vacation. A sign outside reads: "Services resume September 13th."