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<body class='hmmessage'><div dir='ltr'>Hi TRNsys community,<br><br>I am comparing Gas & Electric tankless water heater using the same component (Type 940). According to the description of the type, Electric tankless water heater is simulated by setting the efficiency to 1. When I plot the outlet temperature for both gas & electric heaters, some oscillations occur at the beginning of the first water draw for each day (7 days simulation) only for gas heater (efficiency set to 0.8). I tried to change the deadband, it is not affecting the results. But when I reduce the efficiency of the device, the amplitude of the oscillations increase. Why isn't this happening for the electric heater, i.e. when the efficiency is set to 1 ? Is it just from how the type was designed ?<br><br>Please find attached the file of the simulation and the corresponding weather data. The concerned plots are "Tout" of the 1st and 2nd graphs.<br>Thank you in advance.<br><br>Yours Sincerely,<br>Anas MAJDOULI<br> </div></body>
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