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Find Thermostat installers and replacers in Lake Forest

Avatar for AR Cooling and Heating, LLC

AR Cooling and Heating, LLC

4.92(
50
)
Approved Pro

AR Cooling and Heating, LLC

4.92(
50
)
Approved Pro
Super Service Award
Customers say: Quick response
Recommended by 94% of Angi customers
Recommended by 94% of HomeAdvisor customers
14 years of experience

We are dedicated to providing our clients with the very best in installation, service, and repair for your heating and cooling needs. With 8 years of experience, our company is built on honesty and integrity. We specialize in central A/C and cooling systems as well as heating and furnace systems. We take pride in the quality of our work and our commitment to outstanding results. We look forward to building long-term relationships with our clients, and guarantee your satisfaction.

"Adrain did great and explained everything technically."

Marcos A on May 2025

We are dedicated to providing our clients with the very best in installation, service, and repair for your heating and cooling needs. With 8 years of experience, our company is built on honesty and integrity. We specialize in central A/C and cooling systems as well as heating and furnace systems. We take pride in the quality of our work and our commitment to outstanding results. We look forward to building long-term relationships with our clients, and guarantee your satisfaction.

"Adrain did great and explained everything technically."

Marcos A on May 2025


Avatar for SO CAL BOYS HEATING & AIR INC

SO CAL BOYS HEATING & AIR INC

4.96(
49
)
Approved Pro

SO CAL BOYS HEATING & AIR INC

4.96(
49
)
Approved Pro
Super Service Award
Customers say: True professional
16 local quotes requested
4 years of experience

We are a locally owned and operated company that values honesty and integrity and treats your home as if it were our own. We offer a variety of General Contractor services that are customizable to each individual project. You will find us to be competitively priced, paying close attention to the details of each and every project that we are involved with. We look forward to building lasting relationships and guarantee your satisfaction!

"George & Earvin came out to diagnose my wall heater and were very helpful from start to finish. Highly recommend you give them a call for any HVAC related needs"

Michael S on December 2025

We are a locally owned and operated company that values honesty and integrity and treats your home as if it were our own. We offer a variety of General Contractor services that are customizable to each individual project. You will find us to be competitively priced, paying close attention to the details of each and every project that we are involved with. We look forward to building lasting relationships and guarantee your satisfaction!

"George & Earvin came out to diagnose my wall heater and were very helpful from start to finish. Highly recommend you give them a call for any HVAC related needs"

Michael S on December 2025


Avatar for True Home Heating and Air Conditioning

True Home Heating and Air Conditioning

4.93(
30
)
Approved Pro

True Home Heating and Air Conditioning

4.93(
30
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
13 local quotes requested

True Home Heating and Air Conditioning is committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customer's interests and make their concerns the basis of our business. Please give us a call today!

"Very prompt service to a very urgent need. The professional that responded to our office was outstanding in every way."

VICTOR L on November 2023

True Home Heating and Air Conditioning is committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customer's interests and make their concerns the basis of our business. Please give us a call today!

"Very prompt service to a very urgent need. The professional that responded to our office was outstanding in every way."

VICTOR L on November 2023


"Paul was far better than expected and has proven to have skills, precision execution for each task, customer centric and fair pricing. I highly recommend Paul."

Jeff M on November 2025

From wall repairs touch up, detail painting, wood repairs, refurbishing furniture or just tightening up a simple door knob. Just ask and I'd be more then happy to be of help with anything you need.

"Paul was far better than expected and has proven to have skills, precision execution for each task, customer centric and fair pricing. I highly recommend Paul."

Jeff M on November 2025


Avatar for Drain Right Services, Inc.

Drain Right Services, Inc.

4.38(
50
)
Approved Pro

Drain Right Services, Inc.

4.38(
50
)
Approved Pro
Customers say: Quick response
18 local quotes requested
22 years of experience

We are a full service plumbing company offering residential plumbing services in LA and Orange County. Our expert technicians offer a wide range of services for new installations and complete plumbing repair. Our services include drain cleaning, sewer repair, trenchless sewer, hot water heaters, gas lines, and water filtration systems. We guarantee fast, reliable, affordable plumbing services with up front flat rate pricing, so there are no surprises. Please browse our website to learn more about our company and our plumbing, drain cleaning, sewer repair, and other services. Give Drain Right Services a call today at (800) 208-8875 for more information or to request service at your home in LA or Orange County.

"Terrible people. DO NOT USE. I had my water main line burst at my house and the folks at drain right where in the neighborhood, identified a problem, and knocked on my door. My pregnant wife was home at the time of pipe bust, but was initially unaware of the issue as water was still making it to our home. At first we thought this was a godsend, nice workers who identified an issue wanted to help, how lucky are we. They kindly shut off the water to the house and asked my pregnant wife, who was freaking out by the amount of water shooting out from burst pipe, to sign an authorization form to do work. She was so grateful someone was there to help she happily signed the slip. I was grateful someone was able to help my wife while I was at work. The problem started when I noted what she had signed.. They charged me $341 for a visual inspection. They identified the problem as a tree root that struck a pipe (which was not what in fact happened) and wrote 2 appraisals for solving the issue. The fist solution was replacing the galvanized pipe with another galvanized pipe for $7500. The second was to re reroute the sewer line to our house with copper piping, estimated at a whopping $11,300. I tried to call manager the evening of the pipe bust schedule an appointment as the water was shut off to my house. No response. In fact it took the manager a week to return my phone call to schedule the job, which I had bid out and already resolved. I was recommended a plumber to get a second opinion, and he came promptly and re-routed the sewer line with coper piping for less than half what Drain Right was asking for the job. I have been trying to dispute this invoice with Drain Right for months because its my belief they initially took advantage of my pregnant wife and there terrible service, and instead of returning my phone calls they sent my bill to a debt collection service. What horrible service by a terrible business."

David s on January 2023

We are a full service plumbing company offering residential plumbing services in LA and Orange County. Our expert technicians offer a wide range of services for new installations and complete plumbing repair. Our services include drain cleaning, sewer repair, trenchless sewer, hot water heaters, gas lines, and water filtration systems. We guarantee fast, reliable, affordable plumbing services with up front flat rate pricing, so there are no surprises. Please browse our website to learn more about our company and our plumbing, drain cleaning, sewer repair, and other services. Give Drain Right Services a call today at (800) 208-8875 for more information or to request service at your home in LA or Orange County.

"Terrible people. DO NOT USE. I had my water main line burst at my house and the folks at drain right where in the neighborhood, identified a problem, and knocked on my door. My pregnant wife was home at the time of pipe bust, but was initially unaware of the issue as water was still making it to our home. At first we thought this was a godsend, nice workers who identified an issue wanted to help, how lucky are we. They kindly shut off the water to the house and asked my pregnant wife, who was freaking out by the amount of water shooting out from burst pipe, to sign an authorization form to do work. She was so grateful someone was there to help she happily signed the slip. I was grateful someone was able to help my wife while I was at work. The problem started when I noted what she had signed.. They charged me $341 for a visual inspection. They identified the problem as a tree root that struck a pipe (which was not what in fact happened) and wrote 2 appraisals for solving the issue. The fist solution was replacing the galvanized pipe with another galvanized pipe for $7500. The second was to re reroute the sewer line to our house with copper piping, estimated at a whopping $11,300. I tried to call manager the evening of the pipe bust schedule an appointment as the water was shut off to my house. No response. In fact it took the manager a week to return my phone call to schedule the job, which I had bid out and already resolved. I was recommended a plumber to get a second opinion, and he came promptly and re-routed the sewer line with coper piping for less than half what Drain Right was asking for the job. I have been trying to dispute this invoice with Drain Right for months because its my belief they initially took advantage of my pregnant wife and there terrible service, and instead of returning my phone calls they sent my bill to a debt collection service. What horrible service by a terrible business."

David s on January 2023


Avatar for One Hour Heating and Air Conditioning of Mission Viejo

One Hour Heating and Air Conditioning of Mission Viejo

5.00(
10
)
Approved Pro

One Hour Heating and Air Conditioning of Mission Viejo

5.00(
10
)
Approved Pro
15 local quotes requested
1 years of experience

Here at One Hour Heating & Air Conditioning of Mission Viejo, When homeowners want a reliable air conditioning and heating system that they don’t have to think about, they call One Hour Heating & Air Conditioning. We are the leading HVAC service provider in the Mission Viejo and the surrounding areas for a simple reason: we actually care about your comfort. At One Hour Heating & Air Conditioning® of Mission Viejo, we respect you, we respect your time, and, most importantly, we respect the trust that you put in us to keep your home comfortable. It’s why we back all of our work with a 100% customer satisfaction guarantee for two years, and it’s why we’re always on time—guaranteed. Our customers love what we do because we treat them like the neighbors they are to us. We back our work with a 100% satisfaction guarantee, provide StraightForwardPricing® guides for your benefit, and will pay you back for being even one minute late to an appointment.

Here at One Hour Heating & Air Conditioning of Mission Viejo, When homeowners want a reliable air conditioning and heating system that they don’t have to think about, they call One Hour Heating & Air Conditioning. We are the leading HVAC service provider in the Mission Viejo and the surrounding areas for a simple reason: we actually care about your comfort. At One Hour Heating & Air Conditioning® of Mission Viejo, we respect you, we respect your time, and, most importantly, we respect the trust that you put in us to keep your home comfortable. It’s why we back all of our work with a 100% customer satisfaction guarantee for two years, and it’s why we’re always on time—guaranteed. Our customers love what we do because we treat them like the neighbors they are to us. We back our work with a 100% satisfaction guarantee, provide StraightForwardPricing® guides for your benefit, and will pay you back for being even one minute late to an appointment.


Avatar for QNZ Mechanical

QNZ Mechanical

5.00(
5
)
Approved Pro

QNZ Mechanical

5.00(
5
)
Approved Pro
26 years of experience
Free onsite estimate

At QNZ Mechanical, we provide expert heating, cooling, and electrical solutions for both residential and commercial clients. We understand that comfort, safety, and efficiency are essential which is why our team is dedicated to delivering reliable, high-quality service for every project. From central AC and mini-split installations to advanced zoning systems, air purification, and emergency repairs, we handle it all. We also offer routine maintenance and flexible financing options, ensuring your systems run smoothly year round. With QNZ Mechanical, you can trust our experience, professionalism, and commitment to keeping your home or business comfortable and safe.

"Mike was very knowledgeable and his team was fast. I had my entire ac system replaced the following day with no issues. If you need an AC guy Mike with Qnz is the guy to call."

roberto c on November 2025

At QNZ Mechanical, we provide expert heating, cooling, and electrical solutions for both residential and commercial clients. We understand that comfort, safety, and efficiency are essential which is why our team is dedicated to delivering reliable, high-quality service for every project. From central AC and mini-split installations to advanced zoning systems, air purification, and emergency repairs, we handle it all. We also offer routine maintenance and flexible financing options, ensuring your systems run smoothly year round. With QNZ Mechanical, you can trust our experience, professionalism, and commitment to keeping your home or business comfortable and safe.

"Mike was very knowledgeable and his team was fast. I had my entire ac system replaced the following day with no issues. If you need an AC guy Mike with Qnz is the guy to call."

roberto c on November 2025


Avatar for HVAC Empire

HVAC Empire

5.00(
1
)
Approved Pro

HVAC Empire

5.00(
1
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
3 years of experience

We have a 75$ diagnosing fee. Detailed efficient dependable With over 6 years of experience, I take pride in my quality craftsmanship. We are owner operated, and believe in building long-term relationships with our clients by delivering honesty along with exceptional work. We pride our company on reliability, great communication, integrity, and customer service. We are experts in our trade and will do our best to keep you as educated as we can on your particular project. We work for our customers on their schedule, as to make it as convenient as possible for you! We look forward to working with you!

"Great service. Will not be disappointed"

Sabrina L on May 2025

We have a 75$ diagnosing fee. Detailed efficient dependable With over 6 years of experience, I take pride in my quality craftsmanship. We are owner operated, and believe in building long-term relationships with our clients by delivering honesty along with exceptional work. We pride our company on reliability, great communication, integrity, and customer service. We are experts in our trade and will do our best to keep you as educated as we can on your particular project. We work for our customers on their schedule, as to make it as convenient as possible for you! We look forward to working with you!

"Great service. Will not be disappointed"

Sabrina L on May 2025


Avatar for Personal Plumbing, Heating & Cooling

Personal Plumbing, Heating & Cooling

4.55(
320
)
Approved Pro

Personal Plumbing, Heating & Cooling

4.55(
320
)
Approved Pro
Customers say: Super punctual
42 local quotes requested
26 years of experience

Personal Plumbing Heating, Cooling & Electrical is a company that provides plumbing, Electrical and HVAC services for residential and commercial properties. We offer a range of services including installation, repair, and maintenance of plumbing, electrical and HVAC systems such as heating, air conditioning, pipes, water heaters, and fixtures. We also offer drain cleaning, repairs, and regular maintenance work. Our technicians are knowledgeable and highly trained. We always strive to find a solution and provide top notch customer service. As a Veteran owned and led company, we offer Veteran and senior discounts on most services.

"Took their time explaining the issues and the options available. "

Ian C on December 2025

Personal Plumbing Heating, Cooling & Electrical is a company that provides plumbing, Electrical and HVAC services for residential and commercial properties. We offer a range of services including installation, repair, and maintenance of plumbing, electrical and HVAC systems such as heating, air conditioning, pipes, water heaters, and fixtures. We also offer drain cleaning, repairs, and regular maintenance work. Our technicians are knowledgeable and highly trained. We always strive to find a solution and provide top notch customer service. As a Veteran owned and led company, we offer Veteran and senior discounts on most services.

"Took their time explaining the issues and the options available. "

Ian C on December 2025


Avatar for MSP Heating and Air, LLC

MSP Heating and Air, LLC

4.93(
286
)
Approved Pro

MSP Heating and Air, LLC

4.93(
286
)
Approved Pro
Customers say: True professional
Recommended by 95% of Angi customers
Recommended by 95% of HomeAdvisor customers
84 local quotes requested

We at MSP HEATING AND AIR focus on quality HVAC services over quantity. We use our years of experience and expertise, to complete your project with perfection. Customer service and honesty are the most important aspects of our business and your satisfaction is guaranteed! Please call us today for an estimate. We look forward to working with you! we keep your privacy

"Great service. Will use again for certain "

Mike L on September 2025

We at MSP HEATING AND AIR focus on quality HVAC services over quantity. We use our years of experience and expertise, to complete your project with perfection. Customer service and honesty are the most important aspects of our business and your satisfaction is guaranteed! Please call us today for an estimate. We look forward to working with you! we keep your privacy

"Great service. Will use again for certain "

Mike L on September 2025

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FAQs for thermostat installation and replacement projects in Lake Forest, CA

Smart thermostats may be worth it for many homeowners. They come with various features, including voice control and smartphone apps. Vacation mode can help lower energy usage when you’re out of town for an extended period. Alert warnings let you know about major spikes or drops in temperature. Smartphone apps can track energy usage, and smart thermostats can learn your routine over time to adjust your temperature and reduce wasted energy consumption automatically.

You typically do not need more than one smart thermostat. While it’s common to see multiple mechanical thermostats throughout a large home, multiple smart thermostats may try to override each other. This can lead to problems with the HVAC system. Ensure the unit you buy has the option for dual- or multi-zoned systems to avoid compatibility issues.

Installing a programmable or smart thermostat may save you $180 per year in utility costs. A big part of this comes from a smart thermostat’s ability to learn and adapt to your regular routines. With smartphone apps or web-based interfaces, you also have the option to control your thermostat when you’re not home.

The Lake Forest, CA homeowners’ guide to thermostat installations and replacements

From average costs to expert advice, get all the answers you need to get your job done.