Advocate for the homeless Mitch Snyder accused federal officials yesterday of reneging on their promise to create a model shelter for the homeless, as a deadlock developed over plans to renovate a downtown Washington shelter.

After meeting with the chairman of a federal task force on the homeless, Snyder told reporters that federal officials have rejected his Community for Creative Non-Violence's proposal for a renovated shelter. He and other CCNV members accused the federal government of "playing games with the homeless."

Federal officials, saying the government is standing behind its promise to improve the center, said workers from the General Services Administration are ready to begin work Monday on the old Federal College Building at 425 Second St. NW as soon as the 800-bed shelter is evacuated.

But the CCNV, which now runs the building, said it will not ask its residents to leave until it is satisfied that the government will adequately refurbish the shelter.

"It's just a patch-up job," Snyder said of federal plans.

Snyder, whose 51-day hunger strike last fall prompted President Reagan to promise to renovate the shelter, said the government's plans amounted to a "compromise of the word of the president."

He said he plans to take the government to federal court to force it to operate the shelter if the CCNV decides to stop running the shelter. He also said he would take the issue back to the White House, but stopped short of saying he would start another hunger strike.

Harvey Vieth, chairman of the Federal Task Force on Food and Shelter, said it would be "inappropriate" for the federal government to run a shelter and he said he hoped the government and the CCNV could work out its differences.

He said he was disappointed that no agreement could be reached during yesterday's hour-long meeting.

Vieth said the government stands behind its promise to renovate the shelter. "We are doing exactly what we said we would do," he said.

Among the major improvements that Vieth said the government had agreed to undertake was to build a kitchen and laundry room in the shelter's basement and to bring the building up the D.C. fire codes.

Vieth said the agreement also includes construction of an emergency first aid station, consultation rooms and other repairs.

Federal officials had estimated that the repairs to the shelter would cost between $2 and $5 million. The government's commitment to spend $5 million on the shelter was a condition for Snyder ending his hunger strike.

However, Snyder said yesterday he was dismayed that federal officials were prepared to spend only $5 million on the shelter. He said he consulted with a New York City architect and that the cost of making the shelter a model center is closer to $10 million.

CCNV leaders said they are concerned about the renovation because the group would be responsible for maintenance of the shelter. Snyder said if the renovation is inadequate, CCNV could very well be forced to divert funds from feeding the homeless to fixing windows and plumbing