The Health and Human Services Department, which two years ago requested a $20 million revolving fund to deal with health emergencies such as last fall's Tylenol tragedy, is opposing a House measure to provide $40 million for the same purpose.

The House Energy and Commerce subcommittee on health approved the legislation yesterday, despite objections registered Monday by HHS Assistant Secretary Edward N. Brandt. Brandt said that existing procedures of juggling funds within the agency are adequate to deal with most emergencies.

Another HHS official pointed out yesterday that the Reagan administration has already asked Congress for a $5 million emergency fund for the Food and Drug Administration.

A committee staffer pointed out that three 1981 emergencies--recalls of canned mushrooms, canned salmon and infant formula--left HHS with little flexibility in the event of another crisis.

"We think if a problem like that comes up, we will make a specific request to Congress" for money, said another HHS official, who requested anonymity.

The committee also voted to increase the budget of the National Institutes of Health by 15 percent in each of the next three years, increase primary care block grants from $327 million to $354.5 million next year, and increase block grants for maternal and child health services from $373 million to $483 million.