The great debate continues on the proper setpoint of a thermostat while on vacation or work. It seems like everyone and their mother has their favorite standpoint… some say no more than 5 degrees, others say the higher the better, so which is right?
Before I reveal the proper setback temperature in Arizona, let me make the disclaimer that my job is to help reduce homeowner’s utility bills, and I am a lifelong student and love the building science arena. During college, I dove into the exhilarating subject of psychometrics and aerospace classes, which is the basis for of how we stay comfortable in homes and how heat pumps work to accomplish this goal.
I’ve been in many discussions (sometimes very passionate) about this topic with my air conditioning friends and like you, have done a little research on this topic. I am also doubtful of friends of friends that have worked at an air conditioning company for the last 20 years or even air conditioning techs that proudly say the thermostat should be set no more than 5 degrees from your normal setpoint. That is simply not true, and here is why:
Your heat pump takes 5 – 10 minutes to run at its highest efficiency, and when it is constantly cycling on and off you are using a lot more energy than if the heat pump was continually running. So, if the thermostat is bumped up to 83 degrees while you are at work, and you set it to 78 when you come home, the heat pump does not have as much heat to remove as a 88 degree house and will run less to get to 78.
Plus if your air conditioning system is like 90% of the ACs in Phoenix, it is oversized and will remove the heat even faster than designed. Now, it is a good idea to pre-set the thermostat lower an hour before you come home so it does not take as long to cool your home at 88 degrees. SRP also addresses this old wives’ tale and has a great Q&A here.
Also check out Energy Savers tips on thermostat settings.
Feel free to post your comments and thoughts below and let’s save some energy!
This is a great post by our Arizona Energy Auditor Michael Calderwood, one of the sharpest energy auditors in the valley. Everyone should be aware of people you let in your home who are not certified to the things they recommend. They may talk a good game, but these scams hurt you more often than not, both in the quality of work and your pocketbook to use these people. Enjoy!
#1 First & foremost - An true energy audit should be unbiased and not product specific. If your APS or SRP energy auditor recommends products like radiant barrier, windows or solar these are red flags that you are not getting a true energy audit. We have gone into many homes that have had energy audits done by companies that clearly missed the low hanging fruit of recommendations and instead offered to seal 20 canned lights and put a radiant barrier in a home for almost $8,000. If radiant barriers, canned light sealing or new windows are a major aspect of your auditors recommendations or sales proposals, it's time to politely show your rep to the door and look elseware.
#2 Taking care of business - Be sure that the energy auditor/inspector of choice has the minimum insurance, bonds, licenses and credentials. The minimum requirements for participating in most local programs are:
#3 Proper approach - Make sure the company you are considering takes a whole house approach. They should perform a comprehensive energy audit and also have the resources and capability to perform a full spectrum of appropriate efficiency retrofits. The energy auditor/inspector may cover all aspects from audit/inspection to retrofit, or work closely with certified and authorized partners to handle everything.
We emphasize this point because there are product specific contractors in existence who may use the efficiency audit and audit program platforms to sell their specific products and services regardless of a real or appropriate need.
The bottom line is if you call a company that doesn't specialize and perform a whole house approach to energy auditing and repairs then you may likely be calling out a sales person for a specific product. Ask about the whole house approach to energy efficiency when you call for an energy audit/inspection.
#4 The right tools for the job - The energy auditor should have the right tools for the job. The big question is, "Do they include infrared photos and scanning in the program rate?" If they are charging extra that's a big "NO HIRE" from where we stand. Infrared should be included. Chances are, if they include infrared, they most like have the other tools necessary. However, here is a list of other "must have" equipment items:
#5 No shortcuts - There are certain tasks that are required to be completed for proper energy audit performance and certification. Here they are:
#7 Ask the hard questions - Look, it's your house and your money, you are hiring a professional to be a professional. Let them do what they do. That is why you asked them out. But before hiring, here are some questions you should be able to get solid answers to.
#8 Slow down we just met - Signing documents... You may be required to sign a utility company rebate form and/or a general agreement prior to the inspection. However, some companies may try to get you to sign a contract that states youmust use their company after the audit if you decide to get any repairs done. Be sure that you are signing for audit only and that you are free to use who you want for the repairs - This enables you to get competitive bids, negotiate and make intelligent and qualified decisions.
#9 You paid for it, it's yours - Be sure you own the final report, data and images. The final report is part of what you are paying for. If you decide not to use the auditor's services for the retrofit, then you can supply a copy of reports, data and images to another contractor and skip getting/paying for a second inspection.
FIND YOUR HOME TYPE
Sign Up For Your Home Energy Audit
©2009 – 2017
All Rights Reserved