Selecting the right contractor to install the heating and air-conditioning system in your home!
By Andy Simms
Technical Analyst, Efficiency First California
First start with overall questions: is the contractor a Home Performance Contractor, Is the contractor licensed and is the license active. Check the California contractor’s license board ‘do they carry liability and workmen’s compensation insurance and if so what are the limits? Check their references, past clients and better business bureau and check the financial stability of the company. Ask if the contractor is able to work around children, pets and your schedule, does he clean up the job site every day. How does the contractor structure job payments and how do they handle change orders? Are you and the contractor a good fit? What I mean is that the contractor is going to be working in your home and will your personalities get along, do you have confidence in that person? What is the contractors experience in heating and air-conditioning systems and does he hold any specialty certifications in HVAC.
Understanding the language of the HVAC industry: SEER, EER, COP, AFUE and BTU. Let’s look at seer first. The SEER rating of a unit is the cooling output during a typical cooling-season divided by the total electric energy input during the same period. The higher the unit's SEER rating the more energy efficient it is. Now let’s look at EER, The Energy Efficiency Ratio (EER) of a particular cooling device is the ratio of output cooling (in Btu/hr) to input electrical power (in watts) at a given operating point. A SEER of 13 is approximately equivalent to an EER of 11, and a COP of 3.43, which means that 3.43 units of heat energy are removed from indoors per unit of work energy used to run the air conditioner or heat pump.
The AFUE represents the actual, season-long, average efficiency of a Gas fired furnace. It is a ratio of useful energy output to energy input, expressed as a percentage. For example, a 90% AFUE for a gas furnace means it outputs 90 BTUs of useful heating for every 100 BTUs of Natural Gas input (where the rest may be wasted heat in the exhaust). A higher AFUE means higher efficiency.
Now that you have your head spinning around all you need to know is that all of these ratings are US government standards and that the testing on the appliance was performed in a laboratory and does not represent the efficiency of the unit after it is installed in the home.
The installation of the HVAC system: Remember the efficiency rating that was given to the equipment was established in a lab and after the equipment is installed in the field it can lose between 30 and 50 percent capacity depending on how the contractor installs the system in the home. This is why it is important to select a Home Performance Contractor that is an expert in the installation of heating and air-conditioning systems or he uses a HVAC subcontractor that is an expert.
Questions to ask your contractor: how will you select and size the heating and air-conditioning system for my home? Will you be reusing or replacing my ducts and if you replace my ducts are you going to relocate the registers and replace the register grills. Will you be using Manual J, D, T and S to size the system? And what type of quality control and testing systems do you have in place to make sure that the system that is installed performs to its maximum capability?
Homeowner tips when dealing with your contractor
Rule #1 Always get a load calculation.
Rule #2 Always get a detailed proposal and agreement, in writing, before the work starts.
Rule #3 Always get a building permit.
Rule #4 Always meet the building inspector and get a signed permit upon job completion.
Rule #5 always make the final payment to your contractor after the work is complete and the final inspection
Excerpted from “Contractor to Consumer; the Truth About Heating, Air Conditioning, and Home Comfort Systems” recently written by Joe Gorman of JP Gorman, Inc., Rocklin, CA.
What is a Home Performance with ENERGY STAR®Contractor?
Our CBPCA contractors have gone through extensive training in building science to learn how the house works as a system. Typically, a Home Performance contractor will already have many years experience as a general contractor, insulation or heating, ventilation, air conditioning (HVAC) company or as a consultant, for instance. Our coursework includes in-depth analysis and rigorous hands on experience with the diagnostic equipment and the home’s appliances.
Many contractors fix only the problems they think are most obvious. If a homeowner complains of uncomfortably hot rooms, a HVAC contractor might recommend upgrading to a larger air conditioner. If a house gets too cold during the winter, a contractor might recommend installing a larger furnace. Unfortunately, some HVAC contractors will install the largest, “most efficient” system which may actually be too large for your house, thereby reducing or eliminating any energy savings.
Additionally, these quick-fix solutions aren’t likely to solve your basic comfort issues, nor will they necessarily improve energy efficiency. Such temperature extremes are often symptoms of underlying problems, such as leaky ducts or inadequate insulation which may cause your entire house to under-perform.
Instead of offering a quick-fix, our Home Performance Contractors use a comprehensive whole-house approach to identifying and fixing comfort and energy efficiency problems in your home. The CBPCA Home Performance Contractor employs building science principles and uses sophisticated diagnostic equipment to detect the cause of home performance related problems, much like your mechanic who will run a diagnostic on your car. This systematic approach removes all the usual guesswork and enables our contractors to quickly and accurately address your home’s performance issues.