What can cause high electric bills?
Updated: Jun 8, 2019
It happens to everyone. You come home from work, walk inside after getting the mail only to open your electric bill and find it shockingly high. If you have a high electric bill in the winter, and you heat your Columbus, Indiana home with an electric heat pump, there's a good chance there is a problem with it. Normally the heat pump system is the last thing you would think of because the house has been warm right? WRONG! Just because the house has been warm doesn't mean the system is working properly, it could mean that it's working harder. Often times heat pump problems go unnoticed, then a high electric bill results in a call to the electric company who then comes out with their version of an energy audit. They normally say at this point that everything appears to be normal, however they also suggest you have your heating system checked.
This article is in no way meant to diagnose your heat pump system, only a qualified repair technician can do that. This article is simply to provide the average home owner with a better understanding of their heating system, and to help them make better informed decisions.
Your system will run more often the colder it gets. This is because the colder it gets outside, the faster the temperature of your home can drop triggering the heat pump system to come on. But often a heat pump isn't working as well as it should be, or there is a malfunction going unnoticed causing it's efficiency to suffer. These are the problems that cause a home owner to have higher than normal electric bills. There are a number of things that can effect efficiency, or mislead you into believing that your heat pump is working properly while in fact it's gobbling the power and draining your wallet. Problems such as a failed compressor, low charge, or a blockage in the refrigerant system can easily go unnoticed. A problem such as one of these can occur and you never know it because when you look out at your heat pump everything seems to be running. You hear some noise, the fan is running, and the house is warm. Failed compressors won't pump refrigerant, and thus don't provide any heat to the home. Restrictions in the refrigerant circuit or charge issues such as, to little or to much refrigerant ( Yes there is such a thing as to much refrigerant) Can cause your system capacity to be low. These are just to name a few problems that can cause your auxiliary (backup) heat to run more often and/or for longer cycles. And this results in high electric bills.
A heat pump is two to four times more efficient than your backup auxiliary heat. If your heat pump compressor fails, or a problem exists in the refrigerant circuits, or air delivery system your back up heat comes on more often. Back up heat ranges between 5kw-25kw (10,000 - 25,000 watts) but averages around 15kw for most homes. The common set up in this example will typically utilize 10kw for the back up heat to supplement the system for things such as adjusting the thermostat setting more than a couple degrees. The other 5kw is used to temper cool air when the heat pump reverses it's cycle and switches to defrost. There is no way to take the resistance heat out of the equation but we can reduce the amount of time it needs to be used. Heat pumps are very good at maintaining a temperature, but they are not very effective at RAISING the temperature. That's where the resistance heat comes in. With all the controls, safeties, and limits used in your heat pump system a home owner is limited to what they can do to check or correct a problem with a their heat pump. It is always a good idea if the operation of your heat pump is in question that you call a professional like the folks at Shield Comfort Heating and Cooling Checking such a complex system consisting of numerous controls, safeties, wiring, and high pressure gas require the use of specialized tools. There are a few things however that can be done by a homeowner to help them decide rather or not they should call a repairman.
1) Check the thermostat. I know it sounds elementary, but it's surprising how many times a home owner will mistakenly set the thermostat to EM.Heat instead of Heat mode. This setting bypasses the heat pump all together and uses straight electric heat. Always make certain that you set your thermostat to HEAT, and not EM.Heat. EMERGENCY HEAT, is what that setting is for and it's intended really for that purpose alone.
2) Check your filter. Dirty filters are the source of a lot of nightmares. If your air filter is plugged or heavily loaded down with dirt and other IAQ issues (wondering what IAQ is? find out here. IAQ) your system can't "breath" Properly. The filter will actually slow down the amount of air circulating between the home and the air handler unit. The lack of "air turnover" creates a scenario where the system simply can not keep up with it's load. Not only that, but a plugged filter can also cause much more serious issues and break downs. Restricted air flow also translates to higher compressor operating pressure which leads to compressor burn out or shorted winding. This is a VERY expensive repair which normally indicates it is a good time to think about overall replacement of the system if the system is out of warranty.
3) Turn your thermostat up and give it a few minutes. Then have a look out side and see if your heat pump is running. If it isn't, now is the time to start checking breakers. If you do find a breaker tripped its a good idea to stop there and call a professional from Shield Comfort Heating and Cooling. A tripped breaker may just be innocent coincidence resulting from a surge or brown out. But normally it is an indicator of a serious malfunction somewhere in the system. It's best to let a professional with the education, training and the tools to sort out. Shield Comfort Heating and Cooling offers service in several areas. You can check here, under the Locations tab to see if you live in one of those areas. It is always best to error on the side of caution when dealing with something such as a tripped breaker.
4) Take it's temperature! With a good thermometer, check the return air temperature, and the supply air temperature while the system is heating. You should see between a 15 to 20 degree difference. Note that if the aux backup heat is operating the difference in temperature could be greater.
5) Check the pipes. The outside unit is connected to the inside furnace/air handler by two copper refrigerant lines. One is larger, about 3/4" or so depending on the equipment size, and is insulated with a black foam material. The other is smaller and normally not insulated, and is about 3/8". If the heat pump is running the larger pipe, in the insulation should be very warm. !!CAUTION!! Be careful in checking this! If there is a problem in the refrigerant circuit or air delivery system this pipe can be hot enough to sustain a burn. For this reason we do not recommend simply grabbing the pipe, but use other means to check the warmth or temperature of it. If this pipe is excessively hot, (more than 109 degrees) Check your filter. If the filter is good it's best at this point to call a qualified repair technician. If the pipe is cold, and the outdoor unit is operating, the system may be in defrost, wait 5 minutes or so and recheck. If after the waiting period the larger pipe is still cold, and the smaller pipe is also cold, this likely indicates a malfunction with control system. At this point it's advisable to call a qualified repair technician as the controls are quite complex and require many specialized tools to diagnose. If the pipes are both the same temperature than either the heat pump is not running, or there is a major problem.
As stated, this article is in no way intended to diagnose your system. Only a technician can diagnose, and repair your system properly and return it to a good operational state. But hopefully this article has cleared up some questions and gave you the ability to make a more informed decision about calling in a pro. If you feel it's time to make that call you can click the links below to contact Shield Comfort Heating & Cooling via, email, text, phone, or the convenient contact form.#