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The Elio: HVAC Testing Update | Elio Momentum v76

E-Series Progress- HVAC Testing Update

Earlier this year, we outlined our plans for the E-Series vehicles and the role that each vehicle will play in the testing and validation of our design. In September,we reported that one of our E-Series vehicles, the E1D, was in transit to our heating, air conditioning, and ventilation (HVAC) supplier, RedDOT, for testing. Today, we’re excited to share the first round of testing and E1D’s performance in some extreme conditions.

To test their customer’s HVAC systems, RedDOT uses a full-vehicle environmental chamber that is 48 feet long, 18 feet high, and 18 feet wide. The chamber can create environments of scorching heat, artic cold temperatures and a relative humidity ranging from 20% to 95%. Recently, this chamber tested the E-Series’ air conditioning, heating, and defrost systems.


To validate the Elio’s A/C system, we begin with extreme conditions. The temperature for the environmental chamber, with the E1D inside, was set at a sweltering 110 degrees Fahrenheit at 40% relative humidity. The vehicle was essentially drenched in heat for 24 hours, and for good measure, a bank of heat lamps using 700 W/m² was aimed at a 30% downward angle to replicate the real-world solar effect. Now, the test can begin and the A/C can go to work.

The A/C test tells our engineers everything they need to know about the distribution of air flow throughout the cabin of the vehicle. From this test, we can ensure that the A/C adequately provides cooling to both the driver and passenger. We also conduct this testing using a 3-level method. That is, ensuring that the head, midsection, and feet of the occupants are cooled equally. This ensures that the driver’s brow is as dry as their feet. The results of the A/C testing were in line with our expectations. Now, our engineers can make further refinements to the vehicle for an optimum cabin experience.


The testing of the E-Series heating system was the polar opposite of the A/C tests. For many of us, the thought of starting and heating a vehicle in the dead of winter is an unpleasant prospect. To test the heater, the environmental chamber is cooled to temperatures just below 0 degrees Fahrenheit and soaked overnight. Then, the vehicle’s heater is cranked on to heat the E1D. The heat testing offers similar findings to the A/C testing: air flow, distribution to driver and passenger, and the 3-level method. The temperature inside the E1D rose to comfortable temperatures quickly, similar to most vehicles on the road today.

Defrost: As a part of our HVAC testing, the defrost of the Elio was also tested. The test was conducted following the Society of Automotive Engineers (SAE) standard J902.

In the above photo, you’ll find a RedDOT employee making marks on the windshield to chart the actual defrost pattern. Ultimately, the defrost pattern will match the 95-percentile driver eye position. The engineers are very satisfied with the first round of defrost pattern testing.

Testing the E-Series vehicles is both an exciting and vital phase in our journey. It allows us to validate our design and ensure that we are producing the best possible vehicle. The initial testing of the HVAC system of the E1D is right in line with our expectations and allows our engineers to improve the vehicle based on our findings. The testing of these vehicles represents major progress and will lead to an even better final product.

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