The Heat Handbook Team 
Last updated: July 2026 · Based on 2026 US installed pricing A heat pump replacement costs $4,000 to $9,000 installed for a typical ducted air-source system in 2026, with most homeowners paying around $5,500–$7,000. The range is wide because it depends on the system type, size, efficiency, and your home’s existing ductwork. Here is the … Read more
Last updated: July 2026 · Reviewed against Carrier, Goodman and Mitsubishi service documentation Some frost on a heat pump’s outdoor unit in winter is completely normal — a light coating that the defrost cycle melts away every hour or two. But a unit fully encased in ice is a problem. The causes range from a … Read more
Last updated: July 2026 · Reviewed against Carrier, Goodman and Mitsubishi service documentation A heat pump not cooling usually points to a thermostat setting, a dirty filter or coil, low refrigerant, or a stuck reversing valve. Since a heat pump is essentially an air conditioner that can run in reverse, most cooling problems mirror AC … Read more
Last updated: July 2026 · Reviewed against Carrier, Goodman and Mitsubishi service documentation A heat pump not heating usually comes down to a thermostat setting, a dirty filter or coil, a refrigerant problem, or the unit being stuck in defrost. Because a heat pump both heats and cools, some “no heat” complaints are really settings … Read more
Last updated: July 2026 · Based on Lennox integrated control (board) diagnostic flash codes A blinking red light on a Lennox furnace is the control board telling you exactly what is wrong — in code. The blink pattern (slow flash, fast flash, or a number of flashes) maps to a specific fault, from a normal … Read more
Last updated: July 2026 · Reviewed against Carrier, Goodman and Trane service documentation Water pooling around your furnace is almost always one of two things: a clogged condensate drain on a high-efficiency furnace, or condensation from a problem with a standard-efficiency furnace’s flue. It is rarely an emergency, but you should find the source quickly … Read more
Last updated: July 2026 · Reviewed against Carrier, Goodman and Trane service documentation Short cycling — when your furnace turns on and off every few minutes without completing a full heating cycle — is both annoying and hard on the equipment. The usual causes are a dirty air filter, an overheating furnace, a bad flame … Read more
Last updated: July 2026 · Reviewed against Carrier, Goodman and Trane service documentation A furnace blowing cold air usually comes down to one of five things: a thermostat set to “ON” instead of “AUTO”, a dirty flame sensor shutting down the burners, an overheated furnace on safety lockout, an empty condensate trap, or a pilot/ignition … Read more
Last updated: July 2026 · Reviewed against A.O. Smith and Rheem service documentation A leaking water heater drain valve is the most common repairable source of a bottom leak — and usually the cheapest to fix. The valve is the spigot at the base of the tank used to flush sediment. Most are plastic and … Read more
Last updated: July 2026 · Reviewed against A.O. Smith and Rheem operating instructions To turn off a water heater, you need to stop two things: the power or gas that heats the water, and the cold water flowing into the tank. The exact steps depend on whether you have a gas or electric unit. This … Read more