HVAC and Solar Services Serving All of Solano, Napa & Contra Costa Counties, and the Bay Area

Our Reputation speaks for Itself

A-1 Guaranteed is a family-owned and operated business that serves HVAC and Solar Services Serving All Of Solano, Napa and Contra Costa Counties, Fairfield, Vacaville, and the Bay Area with Heating and Air Conditioning, Solar, Tankless Water Heaters, Windows, Insulation and/ or Duct Replacement needs. As one of the premier service businesses in the area, we have helped thousands of satisfied, loyal customers improve the energy efficiency of their homes and offices.

We are available Monday through Friday and by appointment on Saturday. Our fast and efficient attention to your needs will prove our dedication to our customers is the foundation of our business. Our professional staff is knowledgeable and looks after your best interests when it comes to your environmental comfort needs. We are an Energy Upgrade CA participating contractor. We are honored that our customers consider us #1 in providing trustworthy service and dependable comfort.

Why Choose

A-1 Guaranteed?

  • Voted best heating/cooling company for 14 years
  • Voted Best of The Bay for 5 years of KRON 4 TV
  • Commercial and Residential Installation
  • Angie’s List Super Service Award for 2 Years
  • Energy Upgrade Participating Contractor
  • Factory Trained Installers and Techs
  • Drug-free Environment Enforced and Maintained
  • Better Business Bureau Honor Roll 20 Years
  • Diamond Certified Company
  • North American Technician Excellence (NATE) certified
  • Bay Area Certified Green Business
  • All employees fully background checked for your safety
Recent News


The 4 Components of Ductwork: Are They Costing or Saving You Money?

Think Duct Tape Solves Everything? Think Again.

Arguably one of the most important parts of an HVAC system are the ducts, and yet the majority of homeowners disregard them for years. We need to take a look at the four different components of air ducts that affect the overall health of your HVAC system as well as your home: cleanliness, thermal efficiency, static pressure, and leakage.


A common misconception about ducts is if you can’t see it, it isn’t there – and we’re talking about dirt, dust, debris, and residue inside ducts. Sealing a dirty duct will not make the problem disappear; sealing it only prevents air leaks; it does not remove debris and dirt that could be harmful to people’s health. Another popular (but false) belief is that cleaning out old ducts is beneficial, but in reality, this is not necessary. Attempting to clean the duct will agitate the dirt, causing it to get into the air, which may lead to health problems. If you’re looking for services for your HVAC in Walnut Creek, keep in mind that new ducts are hypoallergenic and if they are properly installed, they will remain perfectly clean for the entire life of the system.

Thermal Efficiency

One of the most crucial factors that goes into ductwork is insulation thickness, or R-value. If you have a new duct system, it probably has high efficiency of R8, which is four times higher than the old ducts, which measure at R2 resistances. The newer ducts can be 100% more efficient than most old ducts! The thicker the insulation rating, the less hot or cool air you’ll lose as you run your system, saving energy and money.

Static Pressure

Static pressure is the measured amount of pressure that is inside your duct system. If the ducts are improperly installed or they are too small, excessive pressure will build up. This amount of pressure relates to the loss or gain of energy, which directly affects the lifespan of the system. The majority of systems tested have levels of static pressure that are double what they should be. If the pressure is higher than recommended, the fan inside of the system cannot get the desired airflow it needs, which will result in more energy trying to make up for the lost amount of airflow. This will decrease the life of your system drastically and increase your energy bills.


Air leaks are a major concern with duct systems, and it would seem to make sense to just seal those leaks to fix the problem. However, ducts that have been sealed still have a leakage rate of 15%, versus a leakage rate of just 6% for new ducts. That’s 55% more leakage! A-1 Guaranteed Heating & Air Conditioning, Inc, however; routinely seals ducts to obtain a leakage rate that is as low as 3% on new and replacement duct systems.

It is important to know when it is time for your ducts to be replaced. If it’s been a long time since new ones were installed in your home, contact us so we can determine the best course of action to get your duct system in top shape. Keeping ductwork in good order reduces energy consumption, reduces your energy bills, keeps the air in your home clean and healthy, and more. If you haven’t had your system checked by professionals in the past, you might have leakage, static pressure that is too high or too low, debris in the system or other issues you may not even realize are there.

Contact the experts of all things HVAC in Walnut Creek and the surrounding areas; get a hold of us today with any questions you might have regarding your ducts. We can help!!

Saving Money with LG Chem RESU10H

How Solar Batteries Cut Costs and Provide Efficient Energy

In addition to serving as a method of powering our homes, there are also many other reasons to switch to using solar power. For one, it is more environmentally conscious, and another is that in the long run, it is more financially viable. Thanks to research done by solar companies in Berkeley, solar powered-batteries like the LG Chem RESU10H are now available through A-1 Guaranteed to bring power to your home in a way that is both energy-efficient and affordable.

The LG Chem RESU10H is an Energy Storage System (ESS) that is meant to keep energy stored to be available for use at a later time. This self-sufficient battery uses stored solar energy to power your home at night, which in turn will greatly reduce the cost of future electricity bills. The LG Chem RESU10H battery improves energy efficiency due to its enhanced ability to use renewable energy, thanks to a stabilized power supply system.

Powerful Performance

The RESU series of LG Chem batteries provides continuous power and round-trip DC efficiency; with its lamination and stacking technology, these battery systems will still retain 80% of their original capacity even after 10 years!

Proven Safety

There is no higher priority than safety. All of the products used for the production of these solar batteries have been certified fully in all current and relevant global standards. LG Chem uses the same ESS products and technology that already have safety records that are both proven and consistent in LG Chem’s automotive technology.

Compact Size & Easy Installation

One of the many benefits of these solar battery units is the size. Lightweight and compact are the defining characteristics of this LG Chem battery, allowing it to fit in discreet places almost anywhere. Its design makes it able to be installed on the floor, and it can even be wall-mounted for both indoor and outdoor use. The installation of the unit takes almost no time at all, which in turn reduces the cost to have it installed, thanks to the simplified inverter connections.

You can get your LG RESU10H in either the 48 V or 400 V size; which one depends on how much power you’ll need for use in your home, and our experts can help you choose the right one. It’s important to choose the right one for your needs because if it’s overpowered, the lifespan of your solar battery will suffer. The same holds true if the battery is too small – it’ll work harder than it was designed for and quit years before it should. Contact us at A-1 Guaranteed to choose the right battery option for your home.

The LG Chem RESU10H solar battery can help you save both money and energy. With this battery providing power to your home at night, your energy usage will decrease, and so too will your energy bills! It’s environmentally responsible, easy to maintain, and in the long run, will surely pay for itself. If you’re interested in learning more about having solar batteries installed, contact the best of the HVAC solar companies in Berkley: A-1 Guaranteed Heating & Air Conditioning, Inc.

Contact us with any questions you may have regarding solar energy services and installation. We’re here to help!

4 Innovative Ways to Save Money on Air Conditioning Power Consumption

Cooling Your Home without the Air Conditioner Running

Summer means many things to different people. To most, it means swimming, cookouts, camping, and baseball games. It really is the season of enjoying the great outdoors and spending time with friends and family. However, one of the defining points of summer can also be one of the most uncomfortable and frustrating: the heat. Some people prefer to stay inside where they have their air conditioners running, and while that is a great way to combat the heat, it is also a great way to spend lots of money and energy. However, there are ways that you can cool off your home without running your AC, and following are a few of them.

1. Add Less Heat Inside

You may not realize it, but inside your home there are many sources of indoor heat ranging from appliances to electronics. Keeping these turned off or limiting their use can cool off your home a great deal. Here are some of the heat sources in your home and how they emit heat:

  • Lighting: Traditional incandescent light bulbs use more of the electricity they use into heat, rather than light. To ensure your light bulbs aren’t giving off heat into your home you can switch to LED light bulbs or fluorescent bulbs.
  • Showers: If you enjoy starting your day with a hot shower, make sure you turn your bathroom fan on to get all the steamy air out of your home. Leaving the steam in your bathroom can let it spread throughout your home and allow heat and uncomfortable humidity to build up.
  • Cooking: Using smaller cooking appliances can help your home stay cool. When you use the oven or the stove, your air conditioning unit has to work harder to get the heat out of your home. You can use a toaster oven, slow cooker, or a microwave to lessen the amount of heat your appliances give off.


2. Absorb Less Heat

There are actions you can take to make your home less absorbent to heat, so you don’t have to run your air conditioner as often. Here is what you can do to make your home absorb less heat:

  • Shade Plants: Plants like vines and shrubs can be put in specific locations around your yard and your home to provide shade. Climbing vines can shade a patio, large plants like bamboo can be put in front of windows to prevent sun shining through, and many other plants can be used to provide shade.
  • A Cool Roof: When it is time to replace your old roof, consider for your next one a roof made out of special materials or ones with coatings that reflect the sun’s rays and result in a cooler interior for your home.
  • Light-Colored Paint: One of the key factors of keeping your home cool in the summer is the color of your home. Painting your house a light color will help it stay cooler in the summertime; dark colors absorb light and heat, while lighter colors reflect them.


3. Insulate and Seal

Adding insulation to your home has many benefits, and the majority of them are apparent in the summer. Having insulation slows down the transfer of heat through walls by interrupting heat transfer, keeping the hot air out and the cooler air inside. There are ways to improve your home’s insulation:

  • Insulate Your Attic: Many people may dismiss the value of insulation but in reality, it matters a great deal. If your attic is well-insulated, it’ll keep hot air up and away from the living areas of your home better. With A-1’s insulation and air sealing services, your indoor air quality will dramatically improve and energy costs will go down, so be sure to contact us for a free, no-obligation quote.
  • Seal Doors and Windows: Sealing air leaks in doors and windows with weather-stripping or caulk can prevent hot air from moving through large gaps and into your home. Most weather stripping is needed at door and window seams.
  • Keep Windows Shut: The mistake people make here is leaving their windows open during the day to get the hot air out of their home. What you should be doing is keep your windows shut during the day because the insulation your windows have can keep the heat out. In the evening is when you should open the windows because that’s when the air has cooled off.


4. Maintain Your Air Conditioner

Keeping your air conditioning unit maintained will ensure that it is running efficiently, and it will prevent it from working harder than it has to. Having a poorly maintained AC unit results in less efficiency, a bigger workload, turning on and off more often, and more repair costs. The best way to maintain your system is by having one of our experts in HVAC in Richmond come out and do it for you. In addition, you can:

  • Clear Away Debris: Make sure there are no dead leaves or tall grass in the condenser unit of your central AC system to open up the air flow and allow heat to disperse efficiently.
  • Clean the Coils: Check your evaporator coil for debris and dust occasionally. An easy way to clear out the debris is using the upholstery attachment on your household vacuum.
  • Keep your thermostat at the highest comfortable temperature setting possible, especially during the day. Don’t turn off your thermostat if you are gone for the day, just turn it up. This puts much less stress on your system.

There are many ways you can keep your home cool in the summer without using your air conditioning non-stop. Not running your AC unit unless it becomes absolutely necessary will be cost-effective for you and it can also improve the lifespan of your unit. To make sure your air conditioner is always running efficiently, take advantage of our maintenance services for HVAC in RichmondContact us for more information

Does It Make Sense Getting HVAC Annual Maintenance?

The Importance of Annual HVAC Maintenance

Many people often question whether it is really necessary to have their HVAC units serviced annually. Plenty of people go years without annual maintenance being done on their systems, so what’s all the fuss about regarding the upkeep?

While you may think annual tune-ups aren’t necessary, what you may not realize is that little by little, without maintenance, your system works harder than it should be, it’s losing efficiency with each passing year, it’s wearing out sooner than it should be, and it’s costing you more money to run. The cost of a tune-up is paid for and then some when you consider all the money you save on heating and AC bills, repair charges, and the cost of a new system when yours fails prematurely due to neglect.

Following are five reasons why it is a good idea to get your HVAC units serviced annually.

1. Regular Maintenance Usually Costs Less Than a Repair Job

There is no way to guarantee that your unit won’t break down if you skip your annual tune-up. It may or may not continue to work through to the next year. However, if it were to malfunction, it would cost you much more than a servicing appointment would. It’s true, tune-ups can’t prevent HVAC unit problems from happening in the future, but during these appointments, your technician can find small problems with your unit and take care of them before they escalate into bigger, more expensive issues.

2. A Well-Cared for HVAC Unit Lasts Longer

If your HVAC unit is serviced annually, it likely won’t need as many repairs (or repairs that are as costly) as a unit that is not annually serviced. Fewer repairs are good news for your wallet, your comfort level, and your stress level! In addition, maintaining your HVAC unit will ensure that it is running at high performance. There are many options available to you if you’re looking for services for your HVAC in Walnut Creek and the surrounding areas with A-1 Guaranteed.

3. A Spring Tune-Up Will Give Your HVAC a Head Start

Springtime is a great time for getting your HVAC unit serviced so it can be ready for the summer. Not only will this ensure that you’ll be nice and cool when the warmer summer months hit, but it will also reduce your chances of being caught off guard with a system breakdown leaving you hot and uncomfortable in the heat. Emergency calls and off-hour service calls can be expensive – reduce the chance that you’ll need one with regular maintenance.

4. Neglecting Regular Maintenance Can Void Your Warranty

Most HVAC units come with a warranty that is limited from the manufacturer. Little do people know that some warranties may call for regular maintenance on your HVAC unit. Make sure you check your warranty to see if this applies to you and if it does, the next step is finding a service company to schedule tune ups for your unit. A voided warranty can be an expensive shock when your furnace or A/C goes out unexpectedly and the repair or replacement costs aren’t covered.

5. The EPA, EnergyStar, and the USDE Recommend Regular Maintenance

Due to the energy efficiency benefits that come along with having your HVAC unit serviced annually, EnergyStar, the USDE, and the EPA all recommend annually servicing yours. It is crucial to have your HVAC systems serviced every year and better yet, twice a year: your furnace in the fall, and your air conditioner in the spring. From saving you the trouble of paying for a repair job, to simply ensuring that your home is kept cool in the summer and warm in the winter, servicing your HVAC units is completely necessary.

The Whole-House-as-a-System Approach

If you’re in need of maintenance for your HVAC in Walnut Creek, we have you covered! We also are the area’s leading insulation and air sealing experts, which are two extremely important components of keeping energy costs and consumption low. We take an approach to home performance that considers a house as an entire system; after all, a well-maintained air conditioner is only going to go so far keeping your home comfortable if poor insulation and air leaks let the cool air escape!

This house-as-a-system approach goes above and beyond what the average HVAC company understands, but it makes sense because each system is directly connected and closely related to the others in a home. Proper insulation and air sealing, in addition to a properly maintained HVAC system, will prevent small concerns from becoming complex problems. For example, what starts out as tiny air leaks in the building’s shell can cause irregularities in the inside pressure, drawing in dirty, unconditioned air from the attic and underfloor areas. Now you’d have an indoor air quality problem, along with possible breathing issues, eye irritation issues, and more. With A-1’s insulation and air sealing services, your indoor air quality will dramatically improve and energy costs will go down, so be sure to contact us for a free, no-obligation quote.
Contact us today to schedule your maintenance appointment or to learn more about how we can improve your entire home performance with insulation and air sealing services.

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