The Heat Handbook Team 
Last updated: July 2026 · Reviewed against Carrier, Goodman and Mitsubishi maintenance guidelines For brand-specific guidance (like Mitsubishi mini-splits), filter cleaning may be monthly. Because a heat pump runs year-round for both heating and cooling, maintenance matters even more than for a furnace or AC — it works twice as many hours. Regular care keeps … Read more
Last updated: July 2026 · Reviewed against Carrier, Goodman and Mitsubishi service documentation Not sure if you even have a heat pump? See how to tell. Many heat pump problems have simple, DIY-fixable causes — a dirty filter, a tripped breaker, a blocked outdoor unit, or a thermostat setting. Others, like low refrigerant or a … Read more
Last updated: July 2026 · Based on manufacturer lifespan data and HVAC industry averages A furnace lasts 15 to 20 years on average, though the real number depends heavily on the fuel type, how well it was maintained, and how hard it worked. A well-maintained gas furnace often reaches 20 years; a neglected one may … Read more
Last updated: July 2026 · Reviewed against Carrier, Goodman and Trane service documentation A furnace not blowing hot air — or no air at all — usually comes down to a thermostat setting, a dirty filter, a blower problem, or the burners failing to fire. Whether the problem is no air or cold air points … Read more
Last updated: July 2026 · Reviewed against Carrier, Goodman and Trane maintenance guidelines Regular furnace maintenance is the single best way to avoid a mid-winter breakdown, cut heating bills, and make your furnace last 15–20 years instead of 10. Most of it is simple enough to do yourself — changing filters, clearing vents, checking the … Read more
Last updated: July 2026 · Based on A.O. Smith serial number dating conventions To find the age of an A.O. Smith water heater, read the first four digits of the serial number: the first two are the year and the next two are the week of manufacture. A serial number starting with 1542 means the … Read more
Last updated: July 2026 · Reviewed against A.O. Smith and Rheem service documentation Replacing a water heater thermocouple is one of the most common gas water heater repairs — and one of the cheapest. If your pilot light lights but goes out the moment you release the control dial, the thermocouple is almost certainly the … Read more
Last updated: July 2026 · Reviewed against A.O. Smith and Rheem service documentation Have a tankless unit? See tankless water heater repair instead. No hot water at all usually means a total failure: a gas water heater with its pilot out, or an electric one with a tripped breaker or failed heating element. Not enough … Read more
Last updated: July 2026 · Reviewed against A.O. Smith and Rheem operating instructions If your gas water heater has no hot water, the pilot light is the first thing to check — if it has gone out, the burner cannot fire. Relighting it is usually a simple DIY job, but if the pilot will not … Read more
Last updated: July 2026 · Reviewed against A.O. Smith, Rheem and Bradford White service documentation A leaking water heater has five likely sources, and where the water is coming from tells you how serious it is. A leak from the drain valve or a connection is a cheap fix. A leak from the T&P relief … Read more