Frequently asked questions

If you have any questions that you could not find the answer to on our FAQ list, feel free to call us at any time. We are here to make your purchase as easy and stress-free as possible.

What are the differences between a single stage furnace, a two-stage furnace, and a two-stage variable-speed furnace?

The “variable-speed” refers to the blower motor of a furnace while the “two-stage” refers to a furnace’s gas valve and burners. A single-stage furnace runs its blower motor and has a fixed gas valve to operate at one single speed at all times.

A two-stage furnace runs its blower motor at one steady speed at a time. The gas valve has two different stages, low fire and high fire. When the furnace first turns on it starts in the first stage, or low fire, and will run the furnace at about 70%-80% of the rated capacity of the furnace. The furnace will go to the second stage, or high fire, on one of two conditions. 1. When the thermostat needs to go higher than 2 degrees or 2. The furnace has been operating for longer than a certain amount of time.

The two-stage variable-speed furnace takes full advantage of both the gas valves high fire and low fire settings and the blower motors multiple speeds and has the highest efficiency possible on the market.

Which furnace is better?

Compared to a single-stage furnace, a two-stage furnace is definitely the better choice. The two-stage furnace operates in low fire longer, ultimately burning less fuel than a single-stage furnace. By using a longer, low output, heat cycle the two-stage furnace is able to minimize temperature swings in your home. Also, a fan running at a longer time at a lower speed increases the effectiveness of the system’s air filters, allowing them to capture and remove more contaminants.

The variable-speed furnace does everything the two-stage furnace does and more! Its advanced technology is able to constantly monitor and adjust its blower settings to account for things in your home that restrict airflow, such as your ductwork, furnace location and even a dirty air filter. Being able to constantly adjust the blower motor means your furnace runs much more efficiently than a single-stage or two-stage furnace so you save energy and money! Customers have reported saving as high as 30% on their electric bills after upgrading to a variable-speed furnace.

What brand furnace/AC is best?

When customers are asked which brands they believe are the best in the industry, they typically say one of three brands. Trane, Carrier, or Lennox. Trane tends to be the best overall. They are the leading name brand in the industry with the most cutting-edge technology. Trane are the ones leading the way on new and efficient methods of heating and cooling your home. By the time other brands are just releasing their first prototypes, Trane has already field-tested and perfected their system. Carrier moved their manufacturing plant to Mexico which has seen a steep decrease in quality control and while Lennox is still manufactured in the US, we will not install them under any circumstance based on their extremely common breakdowns.

All the furnace manufacturers offer a 10-year parts warranty after registering and nothing more. The installing contractor usually offers a 1-year labor warranty. While our economy line furnaces and air conditioners come with a 1-year labor warranty, our Trane systems come standard with a 5-year labor and some of our Trane models even come with a 1-year labor warranty!

Call Bast Heating & Cooling and we will give you a proposal on a new Trane system! We will come out to your home, listen to what you want, conduct proper measurements for sizing the correct furnace and AC and advise you to the best of our ability to make sure you are getting everything you need for a system to make your comfortable for years to come.

How much does a new system cost?

There are many factors that come into play when looking at new systems such as size, efficiency, brand, location and add-ons such as humidifiers, air cleaners, and UV lights to give you the best system for your needs.

Bast Heating & Cooling offers EXCELLENT financing options to make your dream home comfort system the best it can be! We offer 12 months 0% interest financing and also low monthly payment options to fit every customers needs!

Why choose Bast Heating & Cooling?

Three simple reasons. 1. No one in the industry beats our customer service. We have a perfect 5 star rating success rate so far and plan on keeping it that way. 2. We have had 0 call backs on any of our installs. We take pride in our work and do the job correct the first time and last but not least 3. We offer the longest and best warranty. Period. We offer a 10 year parts warranty on all models and on select models we offer Lifetime furnace replacement and a 10 year labor warranty. That’s right, 10 YEARS! That’s 9 years longer than most companies in the area and 5 years longer than even the best warranty we’ve ever seen in Pittsburgh!

Call us today to get a quote on the last furnace you’ll ever have to purchase! You can reach us 24 hours a day, 7 days a week, 365 days a year!

Do you work with Home Warranty Companies?

At this time, we DO work with quite a few different home warranty companies. We do work for American Home Shield, Home Security of America, Cross Country Home Services, Sears Home Services, and others. We also have contracts with a few local housing management companies where we service over 1,000 homes in the greater Pittsburgh area!

If we do not work with your home warranty company yet, feel free to let us know and let your home warranty company know about us! We are ever expanding and always wanting to help new customers!

How much does a service call cost?

Our typical service call is $99 for the diagnosis and covers the first hour of work. The cost of after hours calls (Monday through Friday between 5pm and 8am and weekends) are $325 for the diagnosis and covers the first hour of work.

Do you offer yearly maintenance contracts?

Yes, we do. Our service contracts are only $152 per year and include a furnace clean and check in the fall before it gets cold and an AC clean and check in the spring before the heat comes!

As an added bonus, customers who sign up for maintenance contracts get 10% off on all parts and labor and get priority scheduling!

Do you install humidifiers, air cleaners, or UV lights?

We install humidifiers, air cleaners, uv lights, and more! We have even installed whole house dehumidification systems for customers with high humidity issues. Some of our affiliates and partners include Reme Halo, Aprilaire, and Bosch.

What brand hot water tanks do you install?

We install A.O. Smith, Rheem, and Bradford White traditional hot water tanks. We also install Rannai tankless hot water heaters and Bosch point of use hot water heaters.

What is a variable-speed furnace?

The term “Variable Speed” actually refers to the blower motor inside the furnace or air handler. It’s an electronically commuted motor, or (ECM). ECM’s are DC motors that function using a built-in inverter and a magnet rotor, and as a result are able to achieve greater efficiency than most AC motors.

ECM’s are low-maintenance, energy efficient, and can reduce operating costs. The initial cost of a furnace with an ECM motor will be higher than a traditional furnace, or also known as a single stage furnace, but the typical payback on a variable speed furnace is about 3 years.

Unlike conventional fan motors, a variable speed blower motor runs at different speeds to precisely control the flow of heated or cooled air throughout your home. Better airflow control means a better balance of temperature and humidity.

Using advanced technology, it constantly monitors the data coming from your heating and cooling system and automatically makes adjustments necessary to meet your comfort needs. It varies the amount of circulated air, compensating for factors like dirty filters or blocked vents by increasing the fan speed.

As an added bonus, a variable speed motor gradually ramps up to full speed. This eliminates the sudden, noisy blast of air that’s associated with standard furnace motors. It also reduces the stress on the mounting hardware. In the cooling mode, it allows the air conditioner to remove more moisture from the air.

To put it simply, a variable-speed furnace delivers just the right amount of air for the right level of heating and cooling comfort and saves you about $300 a year in electric bills alone compared to a single stage furnace.

What is a two-speed furnace?

A two-stage furnace operates much more efficiently than a single-stage furnace. It provides the right amount of heat to efficiently satisfy your home and family’s needs. In addition, a two-stage furnace is much quieter since it doesn’t operate at 100% capacity every time it runs, and creates less carbon dioxide emissions for the environment.

If you are in the market for a new gas furnace, then without a doubt, a variable-speed, two-stage furnace would be your best choice! The same applies to heat pumps. Many are available with two-speed compressors and variable-speed air handlers for the ultimate in comfort and efficiency.

For most climates, the first stage operates the majority of the time, and runs at about 65% of the furnace’s full capacity. When the temperature outside becomes extremely cold and the first stage is not sufficient enough to heat your home, the second stage kicks on to provide the additional heat requirements. This allows warm air to be distributed into your home more evenly, which helps to reduce air fluctuations.

Two-stage furnaces also help to increase energy efficiency on moderate-temperature days since they will, in most cases, remain on the low stage. They also provide a higher level of comfort due to a steady flow of warm air on the coldest winter days.

“Variable-Speed” refers to the blower motor - How much air it moves through the duct work. “Two-Stage” refers to the gas valve and burners - basically how much heat it puts out.

Evaporator Coils and Formicary Corrosion

Formicary corrosion is a chemical reaction that occurs in copper based alloys. Formicary corrosion causes pin holes in the actual copper of the evaporator coil. While it is hard to see without magnification, you may see some gray, black, or blue discoloration on the copper’s surface where the corrosion is found.

Formicary corrosion is caused by a chemical reaction requiring three parts: Oxygen, water, and an organic acid. Organic acids, also found in VOCs, are found in many common household products. A VOC is a Volatile Organic Compound and can be found in building materials such as plywood, caulking, glue that is underneath flooring or behind wall paper, oil based paints, tobacco smoke, normal household cleaning solvents, and even makeup.

Oxygen is always present in your home and blowing past your evaporator coil and as warm air passes the cold evaporator coil it creates condensation (water) to form on the copper. As long as there is VOCs present, there is a very high probability that formicary corrosion has begun.

Formic and acetic acid can hurt humans and pets in amounts over 5 parts per million that you breathe in. The infected may experience irritation of the nose, eyes, throat, and upper respiratory tract. Higher concentrations can cause central nervous system effects and damage to the lungs and eyes.

So, how do you stop this from happening? To put it bluntly, with a copper coil, you can’t. The only way to prevent this is to call Bast Heating & Cooling and we can change out your copper evaporator coil with an aluminum coil and your problem with formicary corrosion is solved!

what bast customers are saying...

“Happy to find a trustworthy honest company that looks out for the customer.Brian came out on a Sunday evening to service us. Great work thank you for doing a great job ”

-Geri Huber

“Great experience.Brian diagnosed and fixed my a/c very quickly. Squeezed me in ahead of schedule on a Friday and I did not have to spend a weekend in a hot house. Very courteous and professional. Highly recommend!”


“Brian is a life saver! We went through our home warranty. The first company they wanted to send out couldn't get to our house for 2 weeks! During a heat wave! After a few calls back and forth we got a sooner appointment with Bast. Brian came in the time frame promised. Within 25 minutes of Brian being there the sweet, sweet cold air that hasn't blown in our house for a week began blasting out of our vents. Not only was Brian a genuinely a good person he's an extremely efficient and hard worker. I'll never use another heating/cooling company again.”

-Katie R.

“Very professional.Communication was great and was on time and knew what he was doing. All around a great company to work with and to have work for me."

-Anthony G.

“[Professionalism] Brian was on time in the window he gave, he was very friendly and knowledgeable, he completed the service quickly and got my heart back up and running, would definitely use him in the future“

-Gary B.

“Great experience! It is nice to know that you can still have great local businesses to count on. Was right on time, professional and went above and beyond my expectations. Definitely will recommend.”

-Bekki R.

“[prices were very reasonable] &Brian was able to come over and get my AC back up and running. The prices were very reasonable as well. I would highly recommend his company for and of your heating and cooling needs!!”

-Josh S.

“Very professional, knowledgeable, and efficient. They diagnosed our problem, and replaced our A/C unit the next day.”

-Terry C.

“I am so happy with my service from Max at Bast. He came, diagnosed the problem, got the part and had it fixed all in 24 hours. He was professional and communicative in solving all the problems. One of the best service professionals I've dealt with.”

-Jamie P.

“Very happy with Brian and Max. My old furnace needed some repairs. Replaced 2 parts and checked everything out. Very reasonably priced. My house is nice and toasty, ready for winter. Thank you so much guys! Would definitely recommend Bast Heating and Cooling!“

-Kelly B.D.

“Brian is very professional, knowledgeable and prompt. We’ve needed him twice now, and it’s always a quick and easy experience from scheduling to fixing the issue. Thanks again!”

-Jessica R.H.

“Brian did a great job fixing my AC unit. Very dedicated to his customers!!”

-Erik A.

“Brian is quick to respond, very knowledgeable, reliable, and affordable and most important of all, he is HONEST! You can't go wrong hiring him.”

-Cindy F.