Peterson Mechanical
Company Overview
More than a century of dedicated service
Peterson Mechanical, a family-owned Plumbing, Heating, and Air Conditioning firm originated in Sonoma through the efforts of Ed Peterson. Following Ed's leadership, his nephew Rich Peterson managed the company. Les Peterson, the son of Rich, now leads the company alongside his son Scott and nephew Zach.
Peterson Mechanical serves the North Bay Area, providing mechanical services, renovations, and new construction to a range of sectors such as Medical Facilities, Biomedical, Manufacturing, Electronics, Offices, Schools, and Wineries. We engage in both Plan and Specification and Design Build and Design Assist projects.
Among our current projects are some of the most notable companies on the North Coast, including Agilent Technologies, JDS Uniphase Inc., Medtronic / AVE, Kaiser Hospitals, Sutter Healthcare, St Joseph Healthcare, and Mondavi Winery.
We employ advanced Computer Aided 3D Drafting (CAD) and Computer Aided Manufacturing (CAM) technologies to guarantee accuracy and efficiency in all our work.
Business Services
- HVAC installation or replacement
- HVAC system repair
- Plumbing inspection
- Plumbing installation or replacement
- Water pipe installation
Business Location & Hours
Mon: | 7:30 AM - 4:30 PM |
Tue: | 7:30 AM - 4:30 PM |
Wed: | 7:30 AM - 4:30 PM |
Thu: | 7:30 AM - 4:30 PM |
Fri: | 7:30 AM - 4:30 PM |
Sat: | Closed |
Sun: | Closed |
Recommended Customer Reviews

We had a horrible experience with Peterson. They claimed to fix our heater but did not. I had to call them back a second time to properly fix it. Then they over charged us. When I called about it, they agreed with me and said they would send a revised bill. They never sent it. Instead they sent me to collections! I raced into their office to resolve it. I paid them on the spot.
They said sometimes things get over looked in their billing department, but never asked how they could make things right with me. I was so upset to have my credit damaged for their mistake. They assured me they would contact collections immediately to clear my name.
THREE months later, collections called me again! Peterson STILL had not taken care of things on their end. By this time, I was really upset. Again, not one person at Peterson took responsibility. Their customer service was atrocious.
I created a Yelp account just to save someone else from going through what I went through with them. Dealing with them was a nightmare. Now I have the task of trying to clear the ding on my credit.

I called a competing Furnace/AC company who had done some work in our neighborhood and then called Peterson. Scott Peterson gave me a very detailed proposal and it was $1,900.00 less than the competitor for the same output from the furnace and air conditioner. Dave and Leo, the two installers, both of whom were extremely courteous and professional, spent about 6.5 - 7 hours the first day and then about 1.5 hours finishing up the next day (Dave only). They cleaned up everything that needed cleaning up, they answered all questions I had and everything works much smoother, quieter and much more efficiently than the 25-year-old furnace and air conditioner the new units replaced. I really didn't want to spend the $$$$ replacing these two big-ticket items for the house, but it is money VERY WELL SPENT!

There is a reason these guys have been around for 100 years. Their quote was very competitive for a complex installation that some other providers flat out said they could not do. All the staff we dealt were professional, courteous and clearly knew what they were doing.

I was without heat or air conditioning because my furnace and AC unit was about 30 years old AND all the ducts under the house were torn (some animal with claws had gotten under the house and ripped them to shreds). One call to Peterson Mechanical and Ryan on the phone scheduled me an investigation. Then pronto he scheduled Dave and Chris to do the work. These guys are great - smart, on time, efficient, know what they are doing, answer questions clearly and with patience, neat as a pin, and responsible. They all return phone calls right away. They clean up as they work. They are prompt. They are friendly. And, if you it matters to you (it does to me!) they are most beautifully mannered fellows. It was a huge job completed in a shorter time than I thought it would be. Seamless, every step was followed by a phone call from Ryan who then took charge to get the next step moving along, including the testers and city inspector. Everything looks gorgeous and works beautifully now. Thank you Ryan, Dave and Chris.

Over the 12 years we've lived in our Sonoma home, we've had Peterson in for a few smaller jobs. To date, they were responsive and the work, although minor, was completed satisfactorily. We recently had a fail when turning on the furnace the first time this year and called them. A technician came out and diagnosed a faulty control board. He said they would call us with the price of the part. They called promptly and said it would be $170. The technician showed up a few days later at 8AM (no call from Peterson that he was coming out). He replaced the control board, tested it. He asked if we wanted a new digital thermostat, and since the one we had was from about late 90's, we said yes. He went out to the truck and installed a digital and showed us the basics on how to use it. (He did forget to leave the ""quick reference"" card for the thermostat, and we had to pick one up at Peterson.) We got the bill for the work a few days ago. Peterson's charged $114 for a thermostat that retails for $48.00 and $181 (it was quoted to us at $170) for a control board that retails for $119. We called about the excessive mark up of items we could have ordered ourselves and had the technician install, but they insisted that they charge standard mark-up. Really? Over 100% for the thermostat and over 65% for the control board?? Businesses should know that customers can check prices for just about anything on the internet. Of course they do not pay full retail, so we have no idea what they actually pay for these two items. Needless to say, we'll be looking for another vendor for a new furnace and AC when the time comes.

Scott did an amazing job at installing an HVAC system for my place in Sonoma. He provided a well considered estimate, which was detailed and well documented. The work was done on time and efficiently. Also the final product was great - super good to have it properly and professionally installed. The working crew was highly professional. Thanks to Scott for the work!

The compressor for my three-year-old A/C was rattling badly. Peterson Mechanical's servicemen showed up EARLY, diagnosed the problem quickly (a circuit was blown out), and fixed it right away. Whole service visit was less than 45 minutes. Courteous, efficient, speedy, excellent. Five stars.

I've been a Peterson Mechanical customer for years and they are fantastic. I highly recommend them on a regular basis and will continue to do so. I've used them for my home as well as my office and they've been great at both the residential and commercial side. They are always honest and timely.
They are a family owned and operated business with deep roots in Sonoma Valley which is important to me as a Sonoma local.

This company's incompetent repair work could have caused my niece's home to explode causing major property damage in the least and possibly bodily injury or death. She called them in to repair a wall heater which had previously worked fine and they managed to screw up the repair so badly that the furnace leaked gas because they didn't know what they were doing. They misdiagnosed the problem in the first place and went for the more expensive solution of replacing the main control valve then managed to either install it incorrectly or used the wrong one. It's lucky that when my niece entered the home the next she didn't create some kind of ignition source and blow the place up with her in it. She immediately called PG&E (who were helpful) who came out and shut off the gas. And then on top of all of this Peterson himself gave some song and dance BS excuse for why they screwed up and pointing the blame elsewhere to deflect it from where it really lay. The furnace was in fairly new condition and worked fine for 2 years previously and was checked by PG&E when it was installed. It should have been an easy fix for a competent repair technician but they managed to create a dangerous situation where none existed before. In spite of some of the good reviews here, I'm saying beware of this company. Performing poor work is one thing, but then not taking responsibility for their mistakes is really bad business.

I love this company, especially Jake. He loves to solve repair problems. If you are interested, he will take the time and explain to you what is going on with your furnace, air-conditioner, etc. He has a gift for repairing that which is broken and is personable as well. He is intelligent, proficient, responsible, trustworthy, and has a great personality. This is the second time that we have called Peterson Mechanical. The first was for our air-conditioner. That was about 7 years ago, and we have not had to call for a repair service since. Today, it was for our furnace, and I am so happy that they were there for us. It is wonderful to have the furnace working again.