Heating Cooling HVAC Buyers GuideHVAC Consumers Buyers Guide | Heating & Cooling - The average homeowner or business owner does not know very much about HVAC systems. Therefore, when it comes to buying an HVAC System when it comes time to replace their comfort and conditioning system they simply want an HVAC contractor who will perform the work. Do the work for a reasonable cost and do it right. Finally, to help you with all this we wrote the HVAC Consumers Buyers Guide to help you.

Therefore, how do you find a good contractor that will install your new HVAC system correctly for a reasonable price? Let us explore the possibilities and rules to follow about how a smart homeowner or business owner approaches this and wins.

HVAC Consumers Buyers Guide | Heating & Cooling – The Basics Of Seeking and Finding a Good Contractor

Buying Heating and Cooling Systems for Consumers - energy-efficiency-home-energy-savings1First rule of thumb is to ask people you know about good contractors they have dealt with in the past. Usually, you can get some great leads from good contractors this way. Another method of finding a good contractor is to check online review sites. Sites such as Angie’s List and/or the Better Business Bureau.

This will give you a good idea of how well the contractors do with customers. It will also let you know if you have a problem during or after the work is completed, will the contractor work with you to resolve the problem. Any good HVAC contractor worth his/her salt will always bend over backward to make the customer happy.

As long as the customer is reasonable and the problem is related to the contractor’s quality of work or materials. That includes the equipment you are buying from them.

Homework for Success

2Do your homework and call at least three HVAC contractors when you are getting the heating and cooling system replaced. This is important even if you have a regular and trusted HVAC contractor. It will allow you to see how different contractors approach their sales. Additionally, if your trusted and regular company is taking you for granted or not. Each contractor has their way of cutting corners, so give the contractor a check and see if yours takes you for granted because you are a regular customer.

Load Calculations

HVAC Consumers Buyers Guide

3Any contractor replacing your HVAC heating and cooling system will do a Manual J load calculation on your home or business to make 100% sure the HVAC heating and cooling system they sell to you is correctly sized. No matter what type of system you have, you need a load calculation for the system. Many contractors will try to cut corners on this to save time and sell you a replacement system that is the same size as the old system.

Who knows if the old system was sized properly? Get a load calculation to make sure the new system will be the right size. If the contractor does not offer to make the load calculation, then use another contractor because they are guessing, and you do not want to guess when making a major purchase like this. Many contractors will do a load calculation but not share it with you until you sign their contract.

Manual J HVAC Sizing
HVAC Consumers Buyers Guide

3.1Manual J is a scientific approach to HVAC equipment sizing. It is not difficult for a trained professional to size the home for HVAC equipment. Software is available to make the task easier for anyone to perform a load calculation. The rule of thumb used in the past, and still used by some contractors, is installing the new system based on the size of the old system. Here are some reasons why you should not do that:

  • The house may have been upgraded with new windows and doors.
  • Weatherstripping and insulation values may have changed since the old system was installed. Either for the better or the worst.
  • A house addition may have been added
  • The old system may be inadequate for conditioning certain areas of the home. A big example of this is rooms over a garage.
  • The roofing color may have changed. Yes, this is a factor. It goes with trees surrounding the house for shading. Radiant heat is a factor, and those things contribute to radiant heat.

The manual J takes into consideration the following factors:

  • Number of occupants
  • Duct location - is it in a conditioned or unconditioned space
  • Infiltration - is the house tight or drafty
  • Orientation of the house to the sun
  • Insulation values of the house construction
  • Indoor and outdoor design temperatures. Each geographical region has an average temperature for both winter and summer. Indoor design temperatures are important for the desired average indoor temperature along with humidity conditions. Humidity plays a big role in the comfort and is a part of latent heat loading.
  • Design areas - e.g., a room with many windows needs different design considerations than an inner room with no windows.
  • Elevation - since air is thinner in the mountains at higher elevations the system may need to be upsized by 10% or more for heating.

It is important to get this right. Buying a system that has too much overcapacity can have negative effects on your home. First, it will not be energy efficient. Second, it will cost more. And finally, it could cause problems with humidity and temperature. Sizing is crucial. Some jurisdictions will require the contractor to submit a load calculation with the application for a permit. In that regard, someone is looking over the contractor’s shoulder to ensure they comply with this necessary action.

Contractors Perspective on Sizing

From a contractor’s perspective, many want to get it right. If they install an inadequate system, it will lead to complaints and other problems. Many tend to install a system slightly larger than what the load calculation gives them for figures. In the software, some of the input numbers can be fudged to give them this result. Just be aware that you want a contractor who knows what they are doing when it comes to the phase of the installation. And this usually occurs before the contract is signed.

Additionally, the contractors know the Manual J is black and white. It does not take into consideration some other variables for real-world application. If the customer does not have the budget to replace the ductwork when it really needs to be replaced this causes some issues.

I have turned down jobs for this reason because I know I could not get the system right as it should be done. I have a contractor friend who has also turned down jobs for this reason. If you know, before starting the job, that you can’t get the proper amount of airflow through the evaporator coil then the system will likely have big problems.

After everything is said and done and I walk away from a job after it’s completed, I know without any doubt the customer has a good system that will provide them with many years of comfort. Provided they maintain the system properly.

Manual D and the New HVAC System

3.2Manual D comes into play when you change the size of the system and require new ductwork. Manual D takes into account the size of the ductwork and how much air you need to deliver to each room to satisfy the load. If you are changing the size of your HVAC system you will likely need to change the size of your duct system. I’ve seen the most god-awful duct designs that are truly inadequate and cause problems. 

Manufacturers publish specification sheets for their equipment. Located in the specification sheet for an air conditioner or heat pump. The first thing a designer looks at is the amount of air needed to satisfy the load in every conditioned space. Then they look at all the sizes and types of ductwork they can use to hit that number provided for in the specification sheet for the evaporator coil.

To meet warranty requirements, the contractor must have the pressure specified in the specification sheet. This is why ductwork is important in the overall design. It also affects comfort and unit performance. In other words, if they are out of the ballpark on the pressure, you will not get efficiency or comfort. Your new equipment will also likely not live that long.

The best, and most expensive ductwork, is hard round. This type of ductwork delivers the least amount of friction or turbulence inside the duct. However, it needs to be sized correctly to function properly. That goes with any type of duct system.

More Than Just One Thing

HVAC Consumers Buyers Guide

4Just because you are getting a new system does not mean everything will be good after installation. A good example of this is your ductwork. If you get a new high efficient system and the old ductwork leaks, then the new high efficient system will not be so efficient. A good HVAC contractor will check all this for you and make recommendations. They will also show you the problem areas and explain to you why it would be a good idea to replace or repair the ductwork along with the new system.

Additionally, if the size of your system changes, the size of the ductwork will also need to change.

Lastly, if you have an old R-22 system that is being replaced, insist that a new line set be installed. Some contractors try to cut corners and use the old line set. That can be bad for you in two ways:

  1. The oil from an R-22 system is different than the oil in the R-410A system. Oil migrates throughout the system, including the line set. Residual oil from the R-22 system can have a detrimental effect on your new system.
  2. It is likely the engineering for the new system requires a larger line set for the R-410A system.

Additional Recommendations

HVAC Consumers Buyers Guide

5Other recommendations a good HVAC contractor will do for their customer is to look at the air handler and condenser. Maybe relocate the units to better ideal locations to increase efficiency and reduce noise levels in or near occupied areas. A condenser located near a patio can easily be relocated to another location, so it will not make noise near the patio allowing you to be comfortable when relaxing on the patio. Other things, such as moving the condenser to a location in the shade can help efficiency.

Warranties - Manufacturer and Contractor

6Offering extended warranties and a new thermostat. That, along with the contractor’s company warranty, one-year parts, and labor. These are extras and make the contractor look good by standing behind the product and workmanship. These are things they are selling to you. If a contractor offers this to you in writing, they are possibly much better than the contractor who does not offer these things.

Third-Party Testing of the Final Installation

7HVAC Consumers Buyers Guide - This is not too common but it should be. It is becoming more common in commercial contracting. It is a third-party testing company to come in after the installation is complete. They go over the system and make sure it is operating properly along with installation workmanship & practices checked.


HVAC Consumers Buyers Guide | Heating & Cooling8HVAC Consumers Buyers Guide - Lastly, we encourage you to read the reviews of the many brands of heating and cooling equipment here at High Performance HVAC. You may also check other review sites to check on popular brands of HVAC equipment. However, I have been doing reviews on my site for several years.

It is a common occurrence for negative reviews to be more prevalent than positive reviews. Take the consumer posted opinions with a grain of salt. Why? You may ask? Besides, all the details listed above, that many people miss, or don’t know how many people go for the lowest bidder, or never do their homework to find a good heating and cooling contractor to install their new system? How many of those had the system installed correctly and by code? I would make a bet that many of those people who leave angry reviews about the brand are not pointing their anger in the right place.

Many times that should be with the contractor who likely installed the heating and cooling equipment improperly. Or they got cousin Billy Bob who used to work for a contractor many moons ago to install the system when cousin Billy Bob never really knew what he was doing in the first place. There are many variables to this issue. As a technician in the field for many years, I have seen it before.

HVAC Consumers Buyers Guide | Heating & Cooling

All these things will help you recognize a good HVAC contractor. A good contractor from a contractor that is simply trying to sell you something for a quick buck. The contractor should be genuinely interested in selling you quality work and equipment they trust and know to be good. Follow some basic rules when buying heating & cooling systems and this major purchase can go smoothly.

High Performance

HVAC Consumers Buyers Guide | Heating & Cooling