55 Pa. Code § 6400.69 – Indoor temperature.

(a) The indoor temperature may not be less than 65°F during nonsleeping hours while individuals are present in the home.
(b) The indoor temperature may not be less than 58°F during sleeping hours.
(c) When the indoor temperature exceeds 85°F, mechanical ventilation, such as fans shall be used.

Source

The provisions of this § 6400.69 amended through January 22, 1982, effective March 1, 1982, 12 Pa.B. 384; amended August 9, 1991, effective November 8, 1991, 21 Pa.B. 3595. Immediately preceding text appears at serial page (133681).