Aux heat still doesn't start until the difference between set temp and current temp is 4 degrees. Auxiliary heating turns on automatically to help heat your home more quickly if the temperature drops suddenly. The Nest itself lights up red, indicating that it's aware that it should be using emergency heat. The important thing to remember is that “AUX” heat is fast and dependable but it’s also more expensive than heat … Only run your system in this mode when you truly need it to avoid damaging your central system. When your system reverses itself to defrost the coils, it automatically turns on the radiation strips in order to keep providing your home with warm air. **Note that if your Emergency Heat light is on but your thermostat is NOT set to Emergency Heat, this is an indicator there’s a problem with your heat pump and you should call for advice and service.**. Nest thermostat Heat Pump Balance settings are for systems that have a heat pump and auxiliary (AUX) heat. Emergency Heat is typically triggered when it is 35°F and below outside. Both “auxiliary” and “emergency” heat have to do with the operation of these electrical strips. **Note that if your Emergency Heat light is on but your thermostat is NOT set to Emergency Heat, this is an indicator there’s a problem with your heat pump and you should call for advice and service. Heat Pump Aux Heat vs. If the walls of your home are too cold and your heat pump is not powerful enough, AUX heat may be needed in order to make up the degrees. The E wire normally connects to the ecobee’s W1 terminal. How to minimize the use of auxiliary heat with a heat-pump on your ecobee thermostat Question: We have a heat pump and recently installed an ecobee thermostat. So the signal will either come from the White Wite on W2 or the brown wire on E to turn on the heat strips. At this point, refrigerant gets so cold outside that compressing it becomes nearly impossible, and thus it can’t absorb what little heat is left. Emergency Heat, also known as “auxiliary heat”, is the second stage of heat that your thermostat runs on when the temperature is too cold for your heat pump to extract heat from the outside. So while the heat does turn on at a 2 degree difference, it will blow cool air from that point until the 4 degree swing is met. HEAT" or "EMERGENCY HEAT" instead of "HEATING" (as appropriate) when it is using the electric heating coils. If there's a wire in the W1 connector, make sure it says AUX heat. Once the ice on the heat pump has mostly melted, the heat pump goes back to normal and AUX heat turns off. For those who operate such equipments just now, perhaps you should know the difference between the two rather than just operate on the device blindly. This should only be run when absolutely necessary to avoid damage to your central heating system. But the house just doesn't warm up until it gets above freezing, indicating that the emergency heat is never coming on. In case your heat pump isn't working correctly, you can select to always use alt heat.This video introduces 2 method to force alt heat to turn on.1. For example, if your house is not warm and it’s because something has happened to your outdoor unit, then it’s time to turn Emergency Heat on and call for service. Supplemental heating sources are known as “second-stage” or “back-up” heating. Exactly as the name implies, in emergency situations only. If you look at the backside of Nest Thermostat, you can see labels (O/B , AUX/E) – which means this thermostat is compatible with heat pumps (O/B) and also compatible for heat pumps with aux/emergency heating (AUX/E). So a convenient way to check if a thermostat model is compatible with heat pumps is to check its wiring labels. Air-source heat pumps work on a novel principle: instead of directly producing the heat that you need to keep warm through the winter, the heat pump will find heat energy in the outside air and bring it into your home, using refrigerant as the medium of heat exchange.. Sign Up for Our Brand-New Parks Newsletter. Emergency Heat is when you use your supplemental heat (2nd stage) by itself, without the use of your heat pump (1st stage heat). These supplemental heating sources are things such as the electric resistance heating at the indoor unit, gas, oil or even hot-water back-up systems. The thermostat will sense this and turn on electric heat strips automatically turning on the “AUX” heat light. Your auxiliary heat supplements your heat pump’s heat––it doesn’t replace it. Call Parks Heating & Cooling today at (704) 313-1443 or contact us online to schedule a heating service with our team. However, during cold weather this cycle can actually build frost on your outdoor coil. AUX/AUX1 and AUX2. Otherwise, just keep your thermostat set on “heat.” There is no temperature to switch it over to emergency heat, even if your heat pump is running constantly due to cold weather. Because consumers have many more auxiliary heat options to work with for augmenting heat pumps, this allows them to experience a winter or two in a milder climate zone without the feature before committing to the extra investment, whichever one it may be. Moving heat- In heat mode, your heat pump is like an air conditioner working in reverse to pull heat from the outside to inside your home (the opposite of how it works in cooling mode). Emergency Heat Hello, It's going to be really cold here in Alabama the next few nights and I'm trying to decide what is the best approach to handle the cold nights. Heat pumps need a supplemental heating source. The emergency heat setting has to be manually switched on and should only be used in temperatures below 30 degrees. I'm getting an E33 error, and Nest thermostat is telling me that I can only have one auxiliary heat wire. Virtually all heat pump stats, no matter the age, have both an Emergency switch and an automatic Aux mode (although with older stats, the control logic that activates Aux may be poorly implemented). We are always here to help as much as we can! Simple: during this period, your system turns on a series of electrical radiant heat strips that can still provide you with heat, but while consuming more energy. Essentially, your central heater and air conditioner are the same system, only the direction of refrigerant flow is reversed to heat your home as opposed to cooling it. What Is the Difference Between Auxiliary Heat & Emergency Heat. If you’ve taken even a slightly longer glance at your thermostat, you may have noticed it has a couple of extra heat settings: one called “auxiliary heat” and one called “emergency heat.” While most people know these two settings exist, few people actually know the difference between them. When do I use it? The Thermostat will turn on the heat strips (1) when the temp difference is more than 2-3 degrees (white wire to W2). Continuing to run a heater in these conditions could do tremendous damage to it, so you need to shut it off. The Emergency Heat setting locks out the heat pump and forces the auxiliary heat source (in Minneapolis homes, it’s most likely a gas furnace) to provide 100% of the home’s heating. The outlet temperature with and without Aux heat depends on outdoor temp, wattage of electric heat strips and CFM setting. What is it? So on this blog, the experts at Parks Heating & Cooling take a look at both of them and explain the important differences between the two. Please call to get service when this happens. After making these settings, the Nest "home screen" (showing the current temperature and whether it's heating" will show "AUX. It does not support virtually any other kind of heat pump, such as a 1-stage heat pump with separate 2-stage furnace heating (dual fuel) or a 2-stage heat pump with/without AUX heat. Auxiliary heat is the electric heat strip in your air handler that is supplemental heat. This indicates that Nest is using its "avoid aux. Generally, the NTE will use the heat pump if it needs to heat three degrees or less and auxiliary heating if it needs to heat up four or more degrees. In the usage of a standard heat pump, users often encounter the terms heat and emergency heat. Emergency heat is the same thing as auxiliary heat. They will work in tandem when the temperatures drop to those cold numbers. I have a 20 year old Carrier 3 ton split unit. The diagram on Nest indicates that W1 and W2 are Aux heat, and OB is "heat pump". Heat pump systems have two units - one outside the home and one inside the home. Auxiliary heat uses electric resistance heating, which is much less efficient than your heat pump. *The Nest Thermostat E supports a single stage heat pump with/without AUX heat and a single stage heat pump with separate single stage furnace heating (dual fuel). EM heat is an option on your thermostat that you can manually turn on to activate backup heating. And that’s not necessarily a good thing. The emergency heat setting has to be manually switched on and should only be used in temperatures below 30 degrees. AUX heat turns on to keep you warm. From what I've been reading, W1 is primary heat, W2 is Aux heat and O B is for the reversing valve. This will provide additional heat as needed. It does need to be noted, if your thermostat stays in “Aux Heat” even when temperatures outside rises, you should call to have it serviced. ** Auxiliary Heat. Note: In some cases, your heat pump’s AUX heat could be a gas furnace, but since Phoenix typically has mild winters, some AZ homeowners will have electric resistance as their AUX heat. First “Auxiliary Heat”, “Strip Heat”, “Emergency Heat”, “ Radiant Heat ” are all used to reference the same heating mechanism; your electric heat strips that come with a heat pump. Emergency heating needs to be turned on manually under Settings > Equipment and that will always use your Emergency/Auxiliary heating instead of your heat … Important Notes on Nest Thermostats. It’s used when there’s something wrong with your “first stage” heat. The Emergency Heat Switch on a Heat Pump confuses a lot of people. Emergency heat should only be used on very cold days when the heat pump is unable to keep the house warm. Especially when the weather is below 40 degrees. Aux on the thermostat stands for auxiliary heat. © 2019 AAA-1 HVAC | Site by Possible Zone Marketing. You’d only use this setting when the heat pump malfunctions or is damaged and fails to provide heat . This is when the outside is around 35-40 degrees and the indoor temperature is around three degrees cooler than the thermostat setting. heat pump balance doesn't seem to do anything other than raise the outside temp level that the aux heat is able to kick in. Auxiliary heating turns on automatically to help heat your home more quickly if the temperature drops suddenly. Having Emergency Heat on can and will be more expensive to run. The unit outside your home is a heat pump and the unit inside the home is the auxiliary heating system. and (2) When the thermostat is set to Emergency Heat only (brown wire on E). While they do allow you to continue to get the heat you need in your home to stay both comfortable and healthy, they do cost quite a bit more to run for longer periods of time, which is why they’re a less desirable option. Electric heat strip - This electric heat strip is auxiliary heating (or “aux heat” as it shows up on your thermostat). Thus,when your heater has been on for a few hours, your system will have to defrost itself in order to continue functioning. Both of these heat modes are designed to work in extremely cold temperatures, and choosing the wrong one could have potentially bad consequences for your heater and for your home in general. Your heat pump only is the “first stage” heating. It has run almost continually the last few nights when the … This is why it is only used in an emergency situation. But what happens when you still need heat? Auxiliary heat/ Emergency heat helps the heat pump keep up when cold outside or the temperature differential on the thermostat is large. In order to further understand what these modes do, it’s important to know how a central heater works. No-frills heat pump systems without the auxiliary heat capability sometimes make that feature an add-later option. However, bear in mind that you will be using a considerable amount of extra energy in doing so, thus the name “emergency” being attached to it. When you have temperatures that cold, even the slightest amounts of water vapor in the air can condense and freeze, resulting in frost on your outdoor coil that can result in your entire heater freezing over. Both systems are actually controlled by the device’s thermostat. If you have a heat pump, it is best to increase your heat setting by only two degrees at a time to prevent your auxiliary heat from operating. When the temperature inside your home drops about two or three degrees below the temperature the thermostat is set to, auxiliary heating kicks on to help warm your home more quickly. Different systems and thermostats have different ways of determining when the second-stage heat comes on to assist the heat pump, but it is always done automatically. AUX heat can cost about 2 to 5 times as much as running your heat pump. I assume that the heat pump's "emergency heat" (or maybe "auxiliary heat"?) Knowing the difference between your heat pump’s auxiliary heat and emergency heat will help address the question from above. AUX heat can also start if the pump can’t handle the outside heat on cold winter nights. This allows you to continue to receive heat without the risk of damaging your outdoor heat pump system. Here's the long and short of it. Heat vs Emergency Heat. Therefore, a heating system stuck in AUX heat will run up an energy bill. heat except when really needed" intelligent algorithm. This happens sometimes when it’s colder than average and on the verge of extreme temperature drop like Nashville experienced this last spring. You can choose how much expensive AUX heat your system will use when your heat is running. Types of AUX heat (and why it matters) Heat pumps have 2 forms of AUX heat: Electric resistance (default) Gas furnace; The electric resistance option is like the electric coils you see inside your toaster. Yes, as ridiculous as it may sound, your heater can literally freeze, usually at temperatures of around 40 degrees Fahrenheit or below. Do I turn it on when it’s really cold? When turned on, your compressor and heat pump shut off entirely and your radiation heat strips in your system turn on. This is known as running on “auxiliary heat.” Generally, this can’t be controlled manually, but is instead switched over to automatically when your system either senses that it has been running for too long, or too much ice has built up on the outdoor coil and it needs to begin a defrost cycle. When you turn on Emergency heat, this will only turn on the indoor unit and back-up heat. EM heat is NOT the same thing as AUX heat: AUX heat signifies that your heat pump has automatically switched over to backup heating because temperatures are too low. Emergency Heat is when you use your “second-stage” (supplemental heat)  by itself without using your “first stage” (heat pump). Most of the time, you won’t even notice the switch has happened unless you look at your thermostat and see that the “AUX” light is turned on. Auixiliary Heat will turn on automatically when heat can no longer efficiently transfer heat from the outside air to heat pump. This way, your compressor creates heat by pressurizing your refrigerant before sending it into your home, and then your expansion chamber cools it again when it’s sent back outside. Difference Between Auxiliary Heat and Emergency Heat. I guess the only difference is that AUX is an ‘indicator’ on your thermostat that you are running the heat strips when the switch is set to HEAT. The Auxiliary heat gets automatically turned on by your HVAC system to supplement the heat pump output when your system can’t keep up. However, at temperatures in the 20s and 30s or below, your heat pump may not be able to produce heat at all because there simply won’t be enough in the ambient air to extract. So when should you use your Emergency Heat? If you have any questions, please don’t hesitate to call us! Generally at temperatures below 40 degrees, your system needs to run defrost cycles every few hours to operate. When turned on, the heat pump shuts off entirely, allowing you to receive heat without damaging your outdoor heat pump system. The refrigerant that reaches your coil in this instance is extremely cold, which allows it to still find a way to absorb heat even when the temperature drops to near-freezing temperatures. isn't being activated, because of a wiring problem. I have a Lennox heat pump with electric emergency/aux heat, I also have a humidifier. During freezing weather, the outdoor heat pump will be too cold to quickly heat your home, which is when the auxiliary heating system would kick on. Now I keep on getting alerts that the Aux heat is running. All these are great questions! This is what the “emergency” heat setting is for. We’re available 24/7/365! Auixiliary Heat will turn on automatically when heat can no longer efficiently transfer heat from the outside air to heat pump. That means it has to reverse the flow of refrigerant again in order to allow the hot fluid to flow through your coil and melt off any condensed or frozen snow or ice. And in that case, you should also call a professional for help.. You don’t have to connect your Nest thermostat to your Wi-Fi network. In this video we go over the heat pump balance feature in the programming of the NEST thermostat. Both of these wires are needed for Emergency Heat. 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