HVAC FAQ — straight answers from our techs

    These are the questions our customers ask all the time — written by the same techs who show up at your door, not by a marketing department. If you don’t see what you’re looking for, call (760) 206-8014 or send a message and we’ll add it.

    Troubleshooting

    Why is my AC blowing warm air?

    Warm air means your outdoor unit isn’t moving refrigerant — and there are two flavors of that problem. If the compressor is humming but the air is still warm, you’re probably low on refrigerant, which almost always means a leak somewhere in the system. If the outdoor unit is silent, the culprit is upstream: a tripped breaker, a pitted contactor, a failed compressor or fan motor, a bad pressure switch, or a broken communication wire between the furnace and the condenser. None of these are DIY fixes — call us before you keep cycling the unit and make it worse.

    My AC won’t turn on at all. What should I check?

    Two checks before you call. First: is the thermostat dark? That’s the furnace breaker — usually labeled FAU or “air handler.” Second: is the outdoor unit silent? That’s the AC breaker — a separate circuit. If both breakers are on and nothing is happening, the problem is downstream of the panel: a failed circuit board, a blown capacitor, a stuck safety switch, or a dead thermostat. At that point, stop guessing and call us.

    There’s ice on my AC. Is that bad?

    Yes — ice on an AC is never normal, and running it that way damages the compressor. The cause is almost always one of three things: a restriction in the airflow (clogged filter, blocked return, closed vents), low refrigerant charge, or a failing blower. Turn the unit off, run the fan only to melt the ice, and call us before turning cooling back on.

    Why does my AC keep turning on and off every few minutes?

    That’s called short-cycling, and it’s hard on the equipment — every start-up pulls the highest amperage of the whole cycle. The usual suspects: a pitted contactor that’s chattering, a tripping low-pressure switch (often from a refrigerant problem), a flaky circuit board, or a thermostat that’s mis-reading the room. Don’t keep running it like that — the compressor pays the price.

    My AC smells funny. Should I be worried?

    Yes. Different smells point to different problems: melting plastic = a motor running hot, shut it off; musty / dirty socks = bacteria growth in dirty ducts or coils, time for a clean and probably an oxidizer/UV upgrade; mildew or wet = water standing in the system, usually a backed-up drain. None of these air out on their own without intervention.

    My AC keeps tripping the breaker. Should I just keep flipping it back on?

    No. A breaker that trips on every start is doing its job — telling you something is drawing dangerous amps. Flipping it back is how house fires start. Leave it off and call us.

    Why is my electric bill suddenly $200+ higher when I haven’t changed how I use it?

    AC systems lose efficiency every year — the older the unit, the more electricity it burns doing the same job. The single biggest electricity-eater is start-up: every time your unit kicks on it pulls peak amps for a few seconds. If your bill jumped suddenly without a usage change, the most common cause is a compressor pulling high amps because it’s failing. Worth measuring before it dies on the hottest day of the year.

    My AC is making a buzzing, clicking, screeching, or grinding sound. Which ones do I shut it off for?

    All of them. Each sound points to a specific failure:

    • Buzzing at the outdoor unit — failed contactor, electrical.
    • Clicking — a relay gaining and losing contact, electrical.
    • Screeching or grinding — blower motor bearings going out.

    None of these get better on their own, and running through them turns a part swap into a compressor or motor replacement.

    I just had it tuned up and it broke a week later. Did the tech break it?

    Almost certainly not. Tune-ups are diagnostic — we measure pressures, amps, and capacitor health to find the weak link before it fails. If your tech flagged something and you deferred it, that’s usually what broke. Check your tune-up paperwork: any recommended repairs in writing? If we missed it, we own it. If we flagged it and you held off, the desert eventually collects.

    Maintenance

    How often should I change my filter here in the desert?

    Quarterly at minimum. After a dust storm, check immediately — the Coachella Valley can load a filter in a single windy day.

    Can I hose off the outdoor unit myself?

    Yes — and you should. Higher outdoor temperatures mean higher refrigerant pressures, which means the compressor pulls more amps. A quick spray on the outdoor coils on a 115° day measurably drops both pressure and amperage. Power the unit off at the disconnect, hose top-down (not into the electrical compartment), let it dry, restart. Five minutes, free, extends the unit’s life.

    How often do I need a professional tune-up?

    Twice a year — spring before cooling season, fall before heating. Spring tunes the AC side: refrigerant, electrical, coil clean. Fall tunes the furnace and ducting, which are the lungs of the system. Once a year only addresses half the equipment.

    Should I cover my outdoor unit in winter?

    A breathable top cover is fine to keep palm fronds and leaves out — but it must come off before you ever run the system. A plastic-wrap or full cover left on traps moisture (rusts the cabinet) and suffocates the unit when you turn it on. Tape a reminder note on the thermostat: “remove AC cover.”

    There’s a drip line on the side of my house that drips when the AC runs, then sometimes stops. Is that bad?

    You actually have two drip lines:

    • The lower one is the primary condensate line. It should drip on and off whenever cooling is running — that’s working correctly.
    • The upper one (usually placed above a window where you’ll see it) is the emergency overflow. If water ever comes out of the upper drip line, your primary line is clogged. Call us before the pan overflows into the attic or wall.

    What MERV filter should I run? The store sells MERV 13 and “allergy” filters that claim to be better.

    MERV 13 catches more, but it also chokes airflow — and a starved system ices coils, short-cycles, and burns out blowers. If your system was sized tight for the house (most builder installs are), you want the lightest filter the unit was designed for. If indoor air quality is the real concern, the right answer is usually a dedicated air-cleaner (UV / oxidizer) plus a standard filter — not a thicker filter strangling the existing blower.

    Choosing or replacing equipment

    What size system do I need? Why does sizing matter?

    Bigger is not better — it’s actively worse. Correct sizing is a Manual J calculation based on square footage, insulation, window area, and how leaky your house is. An oversized unit blasts cold air, shuts off before it pulls humidity out, then short-cycles for the rest of the day — every start-up pulling peak amps. Result: clammy house, higher bills, shorter equipment life. Anyone who quotes you tonnage off square footage alone is guessing.

    What’s SEER2 and what number should I look for?

    SEER2 is the seasonal efficiency rating — higher number = less electricity per BTU of cooling. California’s 2026 floor for residential split-systems is SEER2 14.3 (federally mandated). Where the value compounds is in the desert: every SEER2 point up shaves a measurable chunk off August bills. Sweet spot for our climate is usually SEER2 16-18; chasing 20+ rarely pays back the price premium in residential.

    What’s a heat pump and does it make sense out here in the valley?

    A heat pump is the same equipment as your AC running in reverse for heating. The big knocks against heat pumps elsewhere — losing capacity below freezing, defrost cycles — basically don’t apply in the Coachella Valley. We almost never see the temperatures that cripple them. Combined with our electricity cost vs. propane, and the disappearance of natural gas in many new builds, heat pumps make a lot of sense out here.

    Does my warranty transfer if I sell the house?

    It depends on the manufacturer, but the rule of thumb is: a 10-year parts warranty drops to 5 years at the first home sale. Some brands let you formally transfer (with paperwork and sometimes a fee) within 30-90 days of closing — worth doing if you’re selling. We can pull your unit’s registration and tell you exactly what you have.

    My old thermostat broke and the new smart thermostat doesn’t have a spot for the C-wire. Will it just work?

    Sometimes — and “sometimes” is doing a lot of work in that sentence. Most smart thermostats need a constant-power “C-wire” your old mercury-bulb stat didn’t. Options: run a new wire (best), use the add-a-wire kit, or use a 24V plug-in transformer. What you should not do: improvise. One of our top call-drivers is fried control boards from DIY thermostat swaps. A $400 service call to replace a $200 board could have been a 15-minute install if you’d called first.

    Should I repair this thing or replace it? (And how do I tell how old my unit is?)

    Send us the serial number from the data plate on the outdoor unit and we’ll decode the manufacture date for free. The rough rule: under 10 years, repair almost always wins; over 15, replacement usually wins; in between is a real conversation. If your unit runs R-22 refrigerant (anything roughly 2010 or older), the calculus changes — R-22 is out of production and what’s left is priced like rare whiskey. At that point, repair is usually throwing money at a unit that’s outlived its parts supply.

    My system uses R-410A and it just broke. Do I have to replace the whole thing?

    Not necessarily. If you’ve lost refrigerant, you have a leak — which we can usually find and repair without touching the major components. If the compressor or coil has failed, the rule is to replace both as a matched set (mixing old and new pieces in a refrigerant circuit doesn’t end well). R-410A is being phased out for new equipment but is still available for service for the foreseeable future, so an R-410A repair isn’t a dead-end.

    What’s R-454B / R-32? Is the new refrigerant safe?

    R-454B and R-32 are the new low-GWP (global warming potential) refrigerants replacing R-410A on new equipment starting 2025. The EPA carefully examines each new formulation for safety and environmental benefits before it hits the market — these passed. They’re handled a little differently than R-410A, which is why the industry is requiring fresh certification on every installer. Our techs are fully trained and certified on the new refrigerants. We know what we’re doing, and we’re not nervous about working with them.

    Desert-specific

    How long should my AC actually last out here?

    Manufacturer warranties are written for nationwide averages — typically 10 years — and the desert eats that schedule for breakfast. Realistic lifespan in the Coachella Valley: 10-15 years with routine maintenance, 7-10 without. The #1 killer is dirt and debris baking onto the outdoor coil and choking heat transfer. Spring tune-ups and quarterly filter changes are the difference between a 9-year unit and a 14-year unit.

    Why does my AC struggle when it’s 118°F outside?

    AC units are designed to deliver air about 20° below ambient — so at 118° outside, you’re realistically pulling 78° supply air at the vent. From there, the temperature in your house is a battle between that 78° supply and the heat leaking back in through your roof, walls, and windows (your “infiltration rate”). When customers ask why a working AC won’t cool below 78° on a 118° day, the answer is usually insulation and air sealing, not “bigger AC.” Sometimes the best cooling upgrade is attic insulation.

    What should I do when a dust storm is coming?

    Before: close everything (doors, windows, dampers), and set the system to “auto” rather than “on” so the blower isn’t actively pulling outside air through gaps. After: check your filter immediately — a single storm can load a quarterly filter. If you live somewhere this is a monthly problem, look at an electrostatic filter plus a UV / oxidizer cell — that combination is the best defense against the indoor-air hangover after a big blow.

    Is it cheaper to leave it on all day or turn it up when I’m out?

    In the desert, don’t crank it up too far when you leave. A properly sized AC only pulls the indoor temperature down about 1° per hour — so if you let the house climb to 95° while you’re at work, the unit will run flat-out the entire evening to claw it back. That run profile is exactly what wears compressors out. The accepted setback for our climate: 78-80° while you’re out, then 74-76° when you’re home. Wider setbacks save less than you’d think and cost more than you’d guess.

    My place has a unit on the roof (package unit). Is that worse than a split system?

    It’s usually a builder choice — package units are simpler and cheaper to install on flat-roof construction. The downsides: they generally can’t hit the higher SEER2 ratings split systems can, the rooftop location bakes the equipment, and access for service requires a roof trip. They’re not “broken by design,” but if you’re replacing a package unit and your roof and crawlspace allow it, a split system is usually the upgrade move.

    I have a casita, pool house, or converted garage. Mini-split, or extend the main system?

    Mini-split, almost always. Extending the main system to a detached or out-of-the-way space costs you twice: the long duct run loses cold air to the attic before it ever reaches the room, and pulling that capacity off the main system starves the rest of the house. A dedicated mini-split gives you true zoning (independent temperature in that space), modern efficiency, and no impact on the central system.

    My AC has been running 14 hours straight in a heat wave. Is that going to burn it out?

    Yes — and the more important point: a healthy system shouldn’t run 14 hours straight, even in a heat wave. If it’s running constantly and never satisfying the thermostat, something is wrong: low refrigerant, dirty coil, undersized for the load, or a duct leak dumping cooled air into the attic. Don’t let it grind through another day like that — call us.

    Why does my AC freeze up on a cool shoulder-season night when I leave it running for sleeping?

    Counter-intuitive but common: cooler outdoor temperatures actually make icing more likely on a marginal system. Three usual causes: low refrigerant (small leak you’ve ignored), dirty filter or coil (restricted airflow), or running cooling mode below 65° outdoor (most residential AC isn’t designed for it — use heat mode or fan-only instead).

    Do I need a surge protector for my AC? We get brownouts constantly in August.

    Yes. Coachella Valley summer brownouts and storm-related voltage spikes are exactly the conditions a whole-unit surge protector exists for. Compressors and control boards are the most expensive parts of your AC; a $200-400 hard-wired surge device protects against the most common ways those die suddenly. Cheap insurance.

    Money

    Is there still a federal tax credit for a new heat pump or AC?

    No — the federal 25C tax credit for residential heat pumps and high-efficiency AC expired at the end of 2025 under the One Big Beautiful Bill Act. If you bought before 12/31/2025, you can still claim it on your 2025 return. For 2026 installs, the federal money is gone — what’s left is utility programs (next question).

    Do SCE or IID still offer rebates in 2026?

    IID: yes — current programs include up to $400/ton for switching from a gas furnace to an electric heat pump, plus roughly $125-300/ton for high-efficiency AC equipment depending on the efficiency tier and program funding at the time of install. Nobody knows the exact dollar amount until your system is selected and the paperwork is filed — programs change, funding pots empty, and the per-ton math depends on which equipment you choose.
    SCE: essentially nothing meaningful for residential HVAC in 2026.
    What we’ll tell you up front: we know how to get the most out of any rebate you qualify for, and we file the paperwork as part of every install. The rebate has to be applied for before the work begins, so ask us about it before you sign anything — including a quote from someone else.

    What about financing? What are the gotchas?

    We work with three pre-vetted partners: Synchrony, GoodLeap, and Kwik Comfort. The gotchas we won’t put a customer in front of:

    • Deferred-interest “0%” loans that retroactively charge full interest from day one if you miss the payoff window — these get sold as “0% APR” and they’re not.
    • PACE financing (the old HERO / Ygrene programs) that attach the loan to your property tax bill and create issues at refinance or sale. We don’t write PACE.

    What we will offer: straight monthly installments with the rate disclosed up front. If a quote ever says “0%” without a payoff date in big bold letters, ask.

    Ducts, airflow, and the house itself

    Why is the back bedroom always 10° warmer than the rest of the house?

    Two usual causes, often together: that room is the longest duct run from the unit (so it gets the warmest supply air after travel-loss through the attic), and it has no return in the room (so even when the door is closed, conditioned air can’t circulate out). Fixes, cheapest to most expensive: add a return grille, balance the duct dampers, modify the duct run, or put a small mini-split in that room. We can measure airflow at each register to tell you which fix is actually warranted.

    Can I close the vents in rooms I don’t use to push more cold air to the rooms I do?

    No. Your blower is designed to push a specific volume of air; closing vents doesn’t redirect that air, it pressurizes the duct system and strains the motor. Net effect: blower works harder, system gets less efficient, and you usually don’t measurably gain in the rooms you wanted to favor. If you want a cooler bedroom, the answer is duct balancing or a mini-split — not closed vents.

    My ducts run through a 140° attic. How much cooling am I losing before it even gets to the vents?

    A lot — but the honest answer is that nobody knows the exact number until we test it. We use a psychrometric meter to read supply-air temperature at the unit vs. at the register and quantify the loss in your specific house. For ballpark, typical valley construction loses somewhere in the neighborhood of 15-25% of cooling capacity to the attic before it ever reaches a room — but that’s a ballpark, not your number. The #1 fix isn’t more AC, it’s duct insulation and sealing. R-8 wraps on supply ducts and mastic at every joint pays back fast in this climate.

    My AC runs constantly but the house still feels sticky and humid. Isn’t the AC supposed to fix that?

    AC removes humidity as a byproduct of removing heat — but only if it runs long enough cycles. An oversized unit cools the room quickly, shuts off, and never runs long enough to wring water out of the air (this is the most common cause of “cool but clammy”). An undersized or restricted unit struggles for a different reason. Either way, the fix starts with a proper load calculation. In the rare cases that aren’t sizing-related, a whole-house dehumidifier can ride along with the AC.

    Working with a contractor

    What should I ask any contractor before signing a replacement quote?

    Five questions. If a contractor can’t answer all of them in writing, walk away:

    1. Are you licensed, bonded, and insured? (Ask for the C-20 license number, then verify it at the CSLB website — 30 seconds.)
    2. How many of this specific brand and model has your crew installed?
    3. What’s your labor warranty? (Manufacturer parts warranty is separate; labor is what you actually pay for on a service call.)
    4. What happens if it breaks in year 2, year 5, year 10? Get the answer in writing.
    5. Did you do a Manual J load calc, or did you size by square footage? If they sized by square footage, you’re being guessed at.

    Didn’t find your question? We’re happy to talk it through.

    (760) 206-8014 · Contact us