Early Testing at the Emerson Residential Advanced Technologies (RAT) Lab

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1 not only provides comfort in every room of the home, but also extends the life of the HVAC system. Through testing in an Emerson lab, data collected with the Emerson ComfortGuard, and data collected through, we ve demonstrated that is healthier for the HVAC system than a standard thermostat. Early Testing at the Emerson Residential Advanced Technologies (RAT) Lab During Emerson s investment due diligence, in early 2015, the Emerson team installed a full beta system in the Emerson RAT lab in St. Louis. The lab is a small home inside of a lab that can apply heating and cooling loads to individual rooms within the home. The test home system had 7 vents and 5 sensors. The beta vents were made in our lab by hand and had significantly worse airflow characteristics than our current designs. However, despite the beta system s shortcomings, Emerson was impressed with the system s ability to maintain each room s setpoint. In studying s efficacy, Emerson utilized their ComfortGuard product to monitor the HVAC system. ComfortGuard monitors real time supply voltage, supply current, supply air temperature, return air temperature, suction line temperature, liquid line temperature, and duct static pressure. The purpose of ComfortGuard is to collect data to assess the health of the HVAC and prevent failures. Emerson reported to us that caused no measurable impact on power consumption, system wear, or supply air static. Here are some quotes from Emerson s senior leadership after the completion of their testing: Install was very simple great! First impression was cool we were able to get close to room set points (test 1). We never had any issues with the systems physically working (opening and closing). -Jeff Arensnmeier, Senior Staff Scientist I asked engineering if there were any power fluctuations during that testing and they said everything looked good from a performance standpoint. -Steve Cox, Vice President Business Development This successful test was a key component of Emerson s due diligence before leading our Series A financing. There were no more technical questions before investing. Customer X s ComfortGuard In order to validate that extends the life of the HVAC system, we leveraged one of our customers who already had ComfortGuard installed in their HVAC system months before they installed. She gave us full access to her ComfortGuard data so that we could further study the impact of the system. Her home is representative of our average customer home, and has 7 rooms and 16 vents. She lives in Michigan, and during the time period studied there were days when she required both heat and cooling. We ve done a direct A-B comparison of before and after. This data is based on the first half of April 2016 without installed, and the second half of April with installed. This ComfortGuard system monitors fan current consumption, fan voltage supply, supply air temperature, and return air temperature. Page 1 of 6

2 ECOVENT EXTENDS Below is the before and after comparison of fan current draw. The results are striking for a few reasons: significantly reduced runtime significantly reduced short-cycling of the system The data proves that current draw was nearly identical before and after These three points demonstrate ways that can extend the life of an HVAC system. The high peaks in this chart are where ComfortGuard caught the blower start-up current draw peak. Fan Current Draw Comparison Current (A@~225V) Fan Current Draw without Fan Current Draw with /26/16 12: 00 AM 3/31/16 12: 00 AM 4/5/ 16 12:00 AM 4/10/16 12: 00 AM 4/15/16 12: 00 AM 4/20/16 12: 00 AM 4/25/16 12: 00 AM 4/30/16 12: 00 AM 5/5/ 16 12:00 AM Date Figure 1: has no effect on fan current draw. The following charts show supply air temperature for heat and cooling. A similar pattern is seen. Temperature (Heat) Temperature (F) 131 Temperature Before Temperature after /31/16 12:00 AM 4/5/16 12:00 AM 4/10/16 12:00 AM 4/15/16 12:00 AM 4/20/16 12:00 AM 4/25/16 12:00 AM 4/30/16 12:00 AM Date Figure 2: has no impact on heating supply air temperature. Page 2 of 6

3 Temperature (F) ECOVENT EXTENDS Temperature (Cool) 3/31/16 12:00 AM 4/5/16 12:00 AM 4/10/16 12:00 AM 4/15/16 12:00 AM 4/20/16 12:0 0 AM 4/25/16 12:00 AM 4/30/16 12:00 AM Date Temperature Before Temperature After Figure 3: has no impact on cooling supply air temperature. Table 1 summarizes system performance before and after. Table 1: is does not negatively impact HVAC systems. Before After Average Fan Current Draw (Heat, A) Average Fan Current Draw (Cooling, A) Average Heat Cycle Time (min) Average Cooling Cycle Time (min) Temp (Heat, F) Temp (Cool, F) Allows More Airflow vents have been designed to allow more airflow for a given pressure drop than most traditional stamped metal vents. This allows to close vents while maintaining the original airflow through the system. Figure 4 shows an example of the airflow properties of our vents. Page 3 of 6

4 Figure 4: Vents Allow More Air Allowing maximum airflow matters for different reasons in different systems. In a constant speed PSC fan configuration, the fan will always apply the same pressure, but volume flow rate will be reduced in the face of more obstruction. That means obstructions won t damage the fan, but they can cause a heat exchanger to overheat or freeze. A constant volume fan behaves differently; it will ramp up pressure to keep the volume flow rate constant. That causes more wear on the fan, and potentially more leakage in the ducting. is keenly aware of volumetric flow rate and its importance in safely closing registers in an HVAC system. We have also written a white paper on the subject included in this package. Short Cycling Kills HVAC Systems Prevents It Beyond limiting airflow, the fastest way to damage an HVAC system is short cycling. Short run times and short off times between cycles can damage an HVAC system in different ways. Short run times can damage bearings by starving the compressor of oil. Short off times also prevent the oil in the system from stabilizing where it s needed. Short cycling can cause the conditions in the system to change faster than the expansion valve can regulate the refrigerant. Short cycling causes premature wear on the motor, which increases the likelihood of a short forming in the windings. Short cycling is one of the fastest ways to destroy an otherwise properly installed HVAC system. There are many causes of short cycling. One of the most common causes is poor thermostat placement. Half of the problem is that thermostats can only measure temperature in one location in the home. This is exacerbated when it is installed in a location that cools faster than the rest of the house, or it may be near a vent, a return, or Page 4 of 6

5 on a different floor from the rest of the thermal load. By design, the thermostat is fundamentally limited by only detecting the temperature at one point. prevents short cycling in several ways. First, s control algorithm has integrated timers to prevent short cycling that are backed up by timers built into the thermostat. However, in most systems does not rely on the timers. decides to condition a space based on a calculation using sensor readings throughout the home instead of at a single point. In many homes, we have seen HVAC systems controlled only by the thermostat continuously short cycle. With activated, the cycle times lengthened to much healthier levels, thereby increasing comfort and efficiency while protecting the health of the HVAC equipment. The Figure 5 below shows a thermostat operating on the edge of short cycles. A value of 0 means the system is off and 2 means the system is cooling. This system averaged run times of 10 minutes with some cycles as short as 3 minutes. The times between cycles also averaged 10 minutes, but with a predominance of 8 minute rests with a minimum of Thermostat Operational Mode Figure 5: Normal Thermostats Induce Short Cycling Figure 6 below shows conditioning the space with a much healthier run schedule averaging 69 minute run cycles and 166 minutes between cycles. Page 5 of 6

6 Thermostat Operational Mode Figure 6: Prevents Short Cycling increases system life by accounting for the conditioning needs of the whole home and preventing short cycling that occurs with traditional thermostats. Table 2 below shows s impact. This increases the operational lifetime and efficiency of the HVAC system while keeping the home more comfortable. Table 2: Extends System Life by Preventing Short Cycling Before After Average Heat Cycle Time (min) Average Cooling Cycle Time (min) not only provides comfort in every room of the home, but also extends the life of the HVAC system. We ve demonstrated that is healthier for the HVAC system than a standard thermostat through testing in Emerson s lab, data collected by the Emerson ComfortGuard, and data collected through in customer s homes. The analysis presented here is just the tip of the iceberg when it comes to data insights that can be garnered by. The team is uniquely qualified and experienced in signal detection and data analytics to turn temperature and pressure data gathered throughout the home into actionable insights that no other system or device in existence can deliver. Page 6 of 6