Most people have their heat, lights, electricity, and water cut off when they don't pay their bills. But the Republican Congressional Committee will lose its utilities sometime today because the law won't allow it to pay its bills.

For years, Republican and Democrat campaign committees have been occupying House and Senate office space free of charge, even though they are purely political. They do not deal with legislation; they exist only to get people elected.

But with the advent of the Watergate morality, some of the younger members, such as Rep. Allen Ertel (D-Pa.), began agitating for the political campaign committees to vacate the premises. Political committees, they argued, should not be supported by taxpayers' money.

So both parties moved out on the Senate side, and the Democrats left on the House side.

The House Republicans, however, have stayed, despite repeated requests in 1977 from House Speaker Thomas P. O'Neill's, (D-Mass.) to move out. So Ertel got an amendment passed Sept. 30 that no funds may be used for any utilities or custodial services for "any organization which was, during 1977, requested by the Speaker of the House to vacate such premises." The effective date of the law is Dec. 1.

"We must either have authorization to charge rent, or we would have to cut off the heat, electricity, water, and so forth, a spokesman for the Capitol Architect's office said.

The Republicans would like to pay rent, and have offered to do so in order to stay until their new building is completed in March. They paid rent for February through May of this year, but O'Neill returned the checks.

"Now the House can accept our rent," said Republican Congressional Committee spokesman Steve Stockmeyer. "We have offered to pay in good faith. It will probably be March 15 before we can move in to our new building. I guess as we've become more effective, the younger Democrats want to hurt us. They're out for punishment."

A spokesman for O'Neill said the rent was returned because the House parliamentarian ruled that there was "no way" they could accept a rent check.

Ertel is giving no quarter in the fight. He wants the committee out today.

"This is a violation of law," he said. "As an ethical matter, they have no right to be there."

One Democratic source said one possibility is to allow the Republicans to be squatters until they can move into their offices. But, he said, that would still violate the law.

Nevertheless, the GOP is prepared to make a stand, although no one thinks O'Neill will send a squad of Capitol policemen to oust the committee.

"We're prepared to bring in candles and hibachis if we need to," Stockmeyer said. "What we're expecting is a bill. "