Tenant complaint - heat bill / drafts

[Carl Mathis]

New tenant in longtime successfully rented SFR. Unincorporated California - rent control and special tenants rights largely inapplicable due to SFR and no municipality. New tenant says heat bill is too high and wants a specific door replaced they claim is the problem. Never had a heat or draftiness complaint before.
Lease specifies:

13. ACCEPTANCE OF PREMISES: Resident has inspected the premises, furnishings and equipment, and has found them to be satisfactory. All plumbing, heating and electrical systems are operative and deemed satisfactory.

I have contacted the local utility provider about getting previous bills to compare with theirs. Do they have a meaningful complaint or course of action?

Additional context: Tenant seems to be problematic, several lease violations in first month. This complaint looks like a naive perspective motivated by, "I am paying so I get to specify how it is supposed to be" given the nature of the other issues and interactions and the lack of any such complaint from previous tenants.