The furnace failed in January. Does my policy pay for it?
Not under a standard landlord form, because mechanical breakdown is not a covered peril. Equipment breakdown cover reaches it and is inexpensive. Meanwhile the obligation to restore heat is immediate under Arizona law, which is why carrying that endorsement is practical rather than optional.
Pipes burst after the heat failed. Is that covered?
Often yes, where the cause was a sudden failure and the loss followed promptly. Where the building sat cold for a long period, a carrier may treat it differently. Restoring heat quickly protects both the tenant and the claim.
What about a unit that is empty between tenants?
That is where most freeze losses happen. Policies generally require maintained heat or a drained system in an unoccupied property, and on a vacant unit that condition falls on you rather than a tenant. It is worth deciding which approach you take before winter.