O.C. McDonald
Company Overview
Explore our capabilities!
For more than a century, O.C. McDonald Company has been the Bay Area's trusted Mechanical Contractor, specializing in HVAC, plumbing, process piping, building services, direct digital control systems, and building automation. Our services extend across various industries, such as LEED Certified projects, data centers, high-tech clean room construction, process tool installation, heavy industrial piping, commercial, institutional, healthcare, and hospitality. Furthermore, O.C. McDonald applies its rich experience to deliver the right resources to building owners and managers seeking efficient building management. HVAC Contractor, Plumbing Contractor, Mechanical Contractor, Piping Contractor, Heating Contractor, LEED Certified, Sheet Metal Fabrication, Service and Repair, Maintenance.
With over a century of service, O.C. McDonald Company is a prominent name in plumbing, process piping, and HVAC in the Bay Area, recognized as the oldest company of its type in Silicon Valley. Oren Charles McDonald founded the company in 1906, and today it is managed by Jim McDonald, the founder's great-grandson. We are recognized for delivering high-quality workmanship and have executed some of the most challenging installations in the valley. We have built our reputation on the fusion of classic values and innovative technology; together, they provide our clients with reliable quality, excellent customer service, and a contractor who respects deadlines and budgets.
Business Services
- Bathtub repair
- Drain repair
- Faucet installation
- Faucet repair
- Garbage disposal installation
- Gas line installation
- Gas line repair
- HVAC installation or replacement
- HVAC system repair
- HVAC system maintenance
- Plumbing inspection
- Plumbing installation or replacement
- Plumbing repair
- Sewer installation
- Sewer repair
- Shower repair
- Toilet installation
- Toilet repair
- Water heater installation
- Water heater repair
Business Location & Hours
Mon: | Open 24 hours |
Tue: | Open 24 hours |
Wed: | Open 24 hours |
Thu: | Open 24 hours |
Fri: | Open 24 hours |
Sat: | Open 24 hours |
Sun: | Open 24 hours |
Recommended Customer Reviews

We've used O.C. McDonald for years for all of our serious plumbing problems...I say ""serious"" because they are so popular they are always busy and sometimes one just has to get something done right away by ""the other guys"". I did that the other day and was really disappointed; the problem was un-fixed and the reason not well-explained. I called scheduling at OCM and got Debbie, who, in spite of their usual full schedule, was able to schedule me with master plumber, Jason, who appear at my door the next morning, very early in my assigned time slot. Jason inspired confidence with his impressive knowledge bank, his ability to communicate, his deductive ability and his step-wise work. Fixed the problem, explained it well, cleaned-up thoroughly and all for a reasonable price! Did I say I'm a fan?

Great customer service! No hidden fees/prices
This company has been around for over 100 years! Place is pretty old and they are a union shop! So that means their services will be much more than normal places.
The sheet metal shop is open from 7-3pm M-F

I had problems with a toilet for 6 months. Two licensed guys could do nothing but replace wax ring. ""Don"" came out and went the extra mile to pull toilet, put it up on saw horse and test the bowl. Sure enough he discovered manufacturing defect that occurs 1/100.
The guy was good, nice and clean. Can't ask for better. Fair price.

Old school service. I had an oddball request and they weren't able to help me out but the girl on the phone had a couple of great leads and went out of her way to make sure that she did everything possible to make sure I was helped, even though it was obvious that I wasn't going to be spending any money there. I felt like it needed to be mentioned.

Our Old floor heater stopped working so we call another company. The other company said they could not fix it and we needed a new system! My wife went down to OC Mcdonalds and talked to Ron. Ron Said no problem and set up an appointment. A gentlemen named James came to our house and spent 5 hours rebuilding our old 1934 heater and It works great!!!!! James was a very quiet hard working young gentleman. We really appreciate such super service and cannot say enough about James!!!! I would recommend this company to anyone.

Used O,C Mcdonald for the first time at our company today , We had a plumbing company we have used for years but after not be able to get anyone out here we called O.C McDonald to help with moving some pipes for a small office remodel we are doing .
Daniel was very helpful he was able within minutes to locate a shut off that we were unable to locate,he was very efficient and able to explain to me exactly what needed to be done and he complete it very fast, so we could complete on time.
Great Pricing
Customer service in the office was great ( Debbie)
Fast & Efficient
Will definitely be recommending to others !

Since Jan. I have contacted several plumbers to diagnose a problem. After months of getting no where, O.C. Mcdonald was recommended to me. One phone call and next day service fixed a situation that others found puzzling. Cheers to William and Smilin Steve for putting their heads together and finding the cause of my leaking pipe. These two are an amazing team. Besides being very knowledgable, their humor and work ethic is a gift.

I have used O C McDonald for years and have always gotten excellent service. My latest issue ( I always have plumbing issues) was with my upstairs toilet not flushing completely. Debbie sent William over right away he diagnosed the problem and my the next day I had a new toilet that worked great. I will continue to use their service.

Daniel Voss was knowledgeable and honest. Found the problem with our toilet and fixed it quickly. The water shut-off wasn't shutting off, so he fixed that too. He also fixed our bathtub spout (which was incorrectly installed by another plumber)! I won't hesitate to call them for any other plumbing issues! Good people and reasonable prices. They know more and charge less per hour than non-union plumbers I've used in the past. They are our family plumbers now!

I have used O.C. McDonald for several years now. After a few bad experiences with other plumbing companies, I remembered that my father liked O.C. McDonald, so I turned to them and haven't looked back. Each time I've had to call them, the technician has been very nice, very professional and knew what he was doing. The job has always been done correctly and at a decent and fair price. I've never had any problems contacting the office or setting up an appointment.
My latest experience was this past weekend. I had an ""emergency"" with my toilet and wasn't going to be able to take time off work for them to come during regular business hours, nor did I think the toilet would last that long. The dispatcher contacted the technician on call who called me back within seconds. We discussed the problem and he gave me an estimated arrival time, which he met. I might add here, that not only was it a weekend, but it was Super Bowl Sunday! I hadn't realized that when I called, though in reality, I would have still needed someone to come out as the toilet float assembly was gushing water and the valve to shut the water off wouldn't shut it off completely.
Greg was my technician. He was VERY gracious for having to come out on a Super Bowl weekend. He was prompt, professional, kept me informed of what he was doing all along the way, was patient with me which I always appreciate, and he explained the pricing and explained the work he did.
And, as I said above, I've had that same experience with each of the technicians I've had.
I'll be needing my furnace replaced soon, and I know who to call.