Air Conditioning Maintenance

Air Conditioning Maintenance in San Diego County for a System That Works Better and Costs Less

Noticing warm air, weak airflow, or odd noises coming from your AC? At Guthrie & Sons, our 26-point air conditioning maintenance catches problems early and keeps your system in great shape. Whether it’s your home, rental, or business, we’ll get your AC clean, efficient, and ready for even the hottest weather.

Stay Cool, Save Money, and Keep Your AC Going Strong

It’s easy to skip air conditioning maintenance. When your system seems to be working fine, it’s not exactly top of mind. You’re busy, the house feels cool enough, and there’s always something more urgent to take care of. But here’s what we see all the time: clogged filters that choke off airflow, refrigerant leaks that go unnoticed, and dirty coils that force your system to work twice as hard just to keep up. That wear and tear builds up until suddenly your AC isn’t cooling, your energy bill jumps, or something breaks completely—usually on the hottest day of the year.

Every AC system needs maintenance, whether it’s brand new or has been hanging in there for 10+ years. That includes central air, heat pumps, and ductless mini splits. At Guthrie & Sons Heating, Air & Solar, we handle it all—residential and commercial, systems we installed and systems we didn’t. Don’t wait for something to go wrong—contact us for air conditioning maintenance in San Diego, CA, today and keep your cool all year long.

What is an AC Tune Up Anyway?

An AC tune up is a full check-up for your air conditioning system. Our HVAC technicians clean components, test key functions, check refrigerant levels, inspect electrical connections, and make sure everything’s running safely and efficiently.

Obvious benefits? You’ll stay more comfortable and save on energy bills and air conditioning repair services. Lesser-known ones? You’ll keep your warranty valid and extend the life of your AC unit. Whether your system’s brand new, older, or somewhere in between, an AC tune up with us is one of the best ways to protect your investment and avoid those sweaty, mid-summer surprises.

How Often is AC Maintenance Required?

In San Diego, we recommend scheduling air conditioning maintenance services at least once a year, ideally in the spring, before the summer heat hits. That gives us time to catch any air conditioner repair issues and get your system ready for heavy use. If you have a heat pump that also heats your home, it’s smart to schedule a second checkup in the fall.

Common Signs You Need Air Conditioning Maintenance

If your air conditioning unit isn’t keeping up like it used to, these are some of the most common signs it’s time for a tune up:

Warm air coming from your air vents instead of cool air
Weak airflow or inconsistent temperatures
Higher energy bills without explanation
Strange noises or musty smells
AC system is running longer than it used to

If you’re noticing any of these—or it’s just been a while since your last AC maintenance service (or you’ve never had one)—now’s the time. Call or schedule online today and let us help get your AC system back on track. Don’t forget to check out our special offers for extra savings!

PROMOTIONS

CURRENT OFFERS

INSTALLATION

Up to $11,750 Off a New System*

Qualify for HEEHRA and you can get up to $8,000 in HEEHRA rebates, up to $1,150 in manufacturer rebates and up to $2,600 in Federal Tax Credits for a total of up to $11,750 off a new installation. Valid on residential properties only. Cannot combine with any other offers. Must mention promo at time of estimate appointment. Restrictions apply. See dealer for details. Offer valid until funds last.

REPAIR

Free Diagnostic w/ a Repair

Your diagnostic service call fee will be waived if you proceed with a repair. Cannot combine with other offers. Restrictions apply. See dealer for details. Offer expires 5/31/25.

MAINTENANCE

$129 A/C Tune Up

Valid on a central heating or air conditioning system. Price is per unit. Unit must be operating at time of service. Cannot combine with other offers. Restrictions apply. See dealer for details. Offer expires 5/31/25.

INSTALLATION

Free Estimate on a New Installation or System Replacement

Valid for an estimate on a new heating, air, or solar installation or replacement. Restrictions apply. See dealer for details.

Experience the Full Power of Our 26-Point AC Maintenance Checklist

But what sort of regular maintenance does an air conditioner really need? For some AC companies, it’s a quick glance, a bill, and they’re on their way. At Guthrie & Sons, we take it much further—because real air conditioning maintenance should actually improve your system.

We go deep with a 26-point checklist that covers every part of your AC, from airflow and wiring to refrigerant and performance. It’s not about doing the bare minimum—it’s about making sure your system runs better, lasts longer, and keeps you comfortable all season.

Clean Outdoor Unit: We remove debris, dirt, leaves, and more from the condenser coils.
Clean Outdoor Coils: We rinse the coil for better airflow and energy efficiency.
Inspect and Clean Air Cleaner: If your system has one, we clean all components.
Clean or Replace Standard Filter: We’ll clean washable filters or replace disposables. (You supply it, or we can.)
Inspect or Replace UV Bulbs: If you use UV purification, we’ll inspect or swap bulbs. (Bulbs can be supplied or purchased.)

Check and Test Drain Lines: We check for clogs that could lead to leaks or water damage.
Check and Test Condensate Pumps: We make sure pumps are operating safely.
Check and Test Condensate Switches: We verify that the safety switches are working to prevent overflow.

Visual Inspection of Indoor Coil: We check for dirt and corrosion.
Visual Inspection of Ductwork: We make sure it can maintain proper airflow.
Check Line Set Condition: We inspect refrigerant lines for wear, damage, or kinks.

Check Thermostat Operation: We make sure your thermostat is responding and reading accurately.
Inspect and Tighten Electrical Connections: Loose wires cause trouble—we make sure everything is secure.

Inspect Outdoor Fan Blades: We look for cracks or damage.
Test Amps of Outdoor Fan Motor and Compressor: We test for proper performance and early failure signs.

Check Refrigerant Charge and Type: We confirm refrigerant levels are accurate and match your system requirements.
Check Suction and Discharge Pressure: We verify that pressures are within safe, efficient operating ranges.
Check Superheat and Subcool Readings: We take advanced readings to fine-tune refrigerant performance.
Check Outdoor Ambient Temperature: We record outside temps to compare system performance under current conditions.
Check Return Air Wet-Bulb and Dry-Bulb Temperatures: We measure humidity and temperature of return air to assess cooling efficiency.
Check Supply Air Dry-Bulb Temperature: We confirm the cooled air leaving your vents is at the correct temperature.

If you did the math, that’s 26 detailed steps—because your system deserves that level of care. After your air conditioning maintenance, we’ll walk you through what we found. If everything looks good, we’ll show you how to keep it running strong for the season ahead. If we spot something that needs attention, like low refrigerant, a worn part, or signs your system is slowing down, we’ll explain your options clearly, whether that’s a simple AC repair or planning for a future air conditioning replacement. You’ll get a full report for your records (and warranty), and a clear path forward.

Keep Your AC in Top Shape With a Maintenance Plan That Pays Off

Staying on top of air conditioning maintenance shouldn’t feel like a chore, and with our USA Membership Plan, it doesn’t! We’ll remind you when it’s time for service, handle the scheduling, and show up ready to take care of everything from filter changes to system checks. Members enjoy real perks like priority scheduling, discounted service calls, 15% off all repairs, and an upgraded 5-year warranty.

Whether you have a central HVAC system or a ductless mini split, we have a plan that fits your heating and cooling setup and keeps your comfort on track. Call our office or talk to your technician about signing up!

Frequently Asked Questions

Yes, even if your system seems fine, skipping yearly HVAC service is one of the top reasons we get called for AC repair. Over time, wear and tear builds up, and catching small issues early can save you from bigger, costlier problems later. Annual maintenance also keeps your system working efficiently, especially in San Diego’s long cooling season.

We recommend filter replacement every 1–3 months, depending on your home and lifestyle.
Dirty air filters restrict airflow, raise your energy bills, and make your AC work harder. It’s a common reason for many air conditioner repair calls. Changing your filter regularly is one of the easiest ways to improve performance and avoid HVAC issues.

Yes—homes with pets often need more frequent AC service. Pet hair and dander clog filters faster, reduce airflow, and can lead to dirty air filters that affect system performance. We’ll help keep your HVAC system clean and efficient with the right service plan.

Pricing on our air conditioning services in San Diego depends on your system and setup, but we keep it fair and transparent. We offer one-time tune-ups or ongoing HVAC service through our USA Membership Plan, which includes perks like discounted repairs and priority service.

OUR REVIEWS

Real Reviews From Real Customers

We do things differently, and our customers appreciate it. See what some of our thousands of satisfied customers have to say about working with us.

Phil Lane

17:18 10 May 25

Guthrie and Sons has provided great service. There are many HVAC companies in San Diego to choose from. They provided a very reasonable estimate for replacing our two AC systems. Once we said yes installation happened within days. It was a quality install. They answer the phone quickly when I've had questions. Happy to refer them to others.

Dianne Haase

20:57 02 May 25

Great customer service, technicians always on time and friendly. I’ve had my new hybrid heat pump for a few years and Guthrie & Sons are very proactive making sure everything is running smoothly. Very happy in my decision to use them!

Andrea Kossoudji

01:11 30 Apr 25

Great service!! Jonathan was patient, kind, knowledgeable and extremely professional! I love Guthrie & Sons’ reminder system, notification of the technician enroute, the easy invoice system and immediate emailing of the findings, including detailed photographs of the work completed!! Highly recommend!

james beedon

20:47 23 Apr 25

Last summer my air conditioner couldn't cool the house in the hottest period of summer. The HVAC team I was working with came in and said the coils were leaking, the unit was 20 years old. I requested quotes from 5 different companies, and the variation of prices was huge. I went with Guthrie and Sons for these reasons:1. Local Company2. Family Owned3. Great presentation, no pressure4. Good products5. Competitive pricingJust installed yesterday, so jury is still out on the system, but installation was thorough and great communication so far!

Darius Degher

21:45 22 Apr 25

Carson and Michael were brilliant. The heat pump installation went smoothly, and they are really pleasant and trustworthy fellows. The day after it was installed, I had a plumber at my house. He looked at their work and was impressed. He said it was much cleaner than the way HVAC people usually do it.

Lito Ricasata

19:03 08 Apr 25

First time prospective client of Guthrie and Sons. Very responsive staff in providing updates on my calls. Mario F. came over to check out my existing cooling and heating system and is very thorough and professional in providing necessary information related to repair/upgrades. Pending his quote, my experience with Guthrie and Sons is top notch and most highly recommended.Updated review: Kareen, Daniel and Michael worked on the AC replacement, relocation of furnace to the attic and replacement of ductwork. Very professional and knowledgeable team in my opinion. Completed the work in a timely and very satisfactory manner.

Michael Myers

00:19 25 Mar 25

My experience with Guthrie & Sons has been excellent, and I am pleased to write a very favorable review about it. They replaced three air conditioners and three propane furnaces with new equipment that utilizes heat pump technology. I had met with other companies and I was close to coming to a conclusion, when a friend recommended Guthrie & Sons. He told me that they are hyper focused on customer service from beginning to end.Their customer service started with the on line completion of a basic information form. Shortly after submitting that form, I heard from Zach who scheduled an appointment at my home.I had already met with three other HVAC contractors, and for that reason, I had some basic information about the systems available and how heat pumps work and whether propane furnaces should also be installed. I signed a contract on a Friday. By Wednesday of the next week they had completed the installation. Wow.The installation of one of the furnaces in the attic caused minor damage to the drywall. THEY BROUGHT IT TO MY ATTENTION and told me a drywall contractor would be in touch regarding its repair. Two days later it was repaired.Since installation, the equipment (heat pumps from Bosch) has been working great and I am optimistic about the future. Meanwhile, their pricing, warranty and terms are far superior to their competitors.Since this is an unusually long review and so favorable, let me add this: This is my honest, uncompensated opinion. I have no relationship with anyone at Guthrie & Sons other than the contract we executed.

Tom H

15:21 20 Mar 25

We recently had Guthrie and Sons install a Mini-Split system in our home. The entire process was handled professionally with no issues occurring at any time. The estimator (Vlad) went through options with us but let us evaluate the best solution for us with zero pressure. The installation team (Matthew and Aaron) showed up on time, reviewed the scope of the job, made sure they understood what we wanted, and then proceeded to complete the installation exactly as discussed. They asked for my input as needed so there were no surprises when the job was completed.They respected my property and made sure everything was left at least as clean was when they arrived. The job was completed on time and as promised and they reviewed the details of the system and its use clearly. I would definitely have Guthrie and Sons do other electrical/HVAC work should the need arise.

Mike Macias

19:43 19 Mar 25

I have been in the construction industry in San Diego for over 50 years. I owned my own contracting company for over 40 years. I have seen all levels of customer service in my years. The level of customer service from Guthrie and Son’s is among the best I’ve ever seen and received. Every time I hear anyone asking for a referral for HVAC work I immediately give them your number. When I recommend a company I in essence am putting my name and reputation on the line. I refer them with 100% confidence in the service they will receive. Thank you very much for your legendary service.

Scott Sypkens

23:32 11 Mar 25

We first hired Guthrie and Sons to replace a furnace after comparing proposals from several heating and air companies. They’ve since been back for annual check ups, and today Kareen came to diagnose and resolve an issue with our mini-splits. My experience each time, including today, is that they hire friendly, knowledgeable people who do good work. They’ve never tried to upsell or do anything unnecessary, which is the way it should be. I’d recommend them to anyone who asks.

Marilyn Rivas

20:07 09 Mar 25

They always come out quickly. They are so polite and careful.

Steven Wheeler

19:28 07 Mar 25

Good technician did everything right yet our heater still not workingJonathan gave us the likeliest problems so we’ll have to get it fixed

Dmitriy

04:01 07 Mar 25

My AC was not working for seven months. Three other companies tried to fix it with no success. Don’t make the same mistake I did—go straight to Guthrie & Sons! They are absolutely worth every penny.

Cecilia Benevich

22:17 05 Mar 25

Rick

21:38 05 Mar 25

Experienced technician gave me the particulars of a replacement HVAC system

Daylan Dauchot

21:28 05 Mar 25

Courteous, in-time, helpful, honest. Would recommend.

Xinxin Wang

22:05 04 Mar 25

Tom Barden

18:26 04 Mar 25

Adair Cooke

19:02 03 Mar 25

Jonathon is a great technician. He is very willing to answer any questions and explains things very well. He is very transparent with letting us know cost, finance options, different furnace models and anything else we want to know. I would highly recommend him to anyone looking for furnace repair or replacement.

Bratso Krsic

00:29 28 Feb 25

Guthrie and Sons took on the challenging project of installing an HVAC system at St. George's Serbian Orthodox Church of San Diego, CA. They were the only company among the six we consulted that saw the project through to the end. The members of our congregation are not just happy, but thoroughly satisfied with the heating and air conditioning. The system, split units/floor units with condensers outside, was installed with minimal intrusion onto the church's artwork. Despite the project taking longer than expected due to permit delays, the results were well worth the wait. We highly recommend Guthrie and Sons Heating and Air.

CONTACT US

Schedule Your San Diego Air Conditioning Maintenance With Guthrie & Sons

Every summer, we get called in for emergency AC repairs that could’ve been prevented with a little routine maintenance. If you want to avoid major problems and costly repairs, we’re here to help. Guthrie & Sons Heating, Air & Solar provides expert air conditioning maintenance in San Diego, California, plus reliable service to surrounding cities. From tune-ups to full AC service plans, our HVAC company offers what your cooling system needs to last. Schedule service today!

Air Conditioning Maintenance