I think I recall some discussion about implementing deadbands into thermostat controls, but I don’t think it happened. It may not work well with other simulations of equipment energy use, but I don’t know that for sure. A heating temperature
control works by turning on the heat, overheating past setpoint before turning off, and then coasting below setpoint before turning back on. Cooling works the opposite way. You can implement this type of control using EMS programs. You need to know some
computer programming and find the correct points to monitor and control. Your EMS program can either control heating and cooling directly or manipulate the setpoints up or down based on the room air temperature, which is artificially well mixed in E+. Ned Lyon, P.E. (MA, WV) SIMPSON GUMPERTZ & HEGER
From: EnergyPlus_Support@xxxxxxxxxxxxxxx <EnergyPlus_Support@xxxxxxxxxxxxxxx>
My temperature setpoint schedules follow one setpoint for heating and one for cooling which were provided by the project team that built the houses. I would like to model the deadband
around those setpoints. For example, if a heating setpoint were 74F and there was a temperature deadband of 3F, the HVAC would not turn on until indoor temperature reached 77F. I would like for the indoor temperature of my model to fluctuate some instead of staying exactly at setpoint.
And I am using real weather data that was measured in the backyard of one of the houses. Thanks, Evan From:
Jim Dirkes Jim@xxxxxxxxx [EnergyPlus_Support]
A few thoughts..... I'm not sure what sort of deadband you're trying to model, but...
James V Dirkes II, PE, BEMP, BCxP
Team Lead - Building Performance
616 450 8653
Foresight Management
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40% of the value the 99% enjoy is created by 1% of the people. From:
EnergyPlus_Support@xxxxxxxxxxxxxxx <EnergyPlus_Support@xxxxxxxxxxxxxxx> on behalf of Evan Jones
evan_jones0212@xxxxxxxxxxxx [EnergyPlus_Support] <EnergyPlus_Support@xxxxxxxxxxxxxxx>
Hello, I have developed a E+ models of a few houses with differing heatpumps. Two variable capacity, a 1-stage, and a 2-stage. The latter two were installed in 2010, and had a thermostat with
a very large temperature deadband. I am having difficulty reducing my HVAC power error to within 15% at a monthly level during shoulder months like April and October. I have found that it is mostly due to measured indoor
temperatures deviating from the temperature setpoint within a wide deadband. In my EnergyPlus models, the indoor temperature stays strictly at the set point with no deviation. For some days, the deadband in the actual homes allows the HVAC to simply stay off
and for the temperature to fluctuate inside, while in my EnergyPlus model both heating and cooling turns on throughout the day so that the indoor temperature remains at setpoint.
This problem is exacerbated by the 1- or 2- stage heat pumps. Since they are worse at keeping indoor temperatures steadily at setpoint than variable capacity heat pumps, their errors
become much higher and are evident in more months. I have done some research into the issue and found that it is caused by EnergyPlus’s method of modeling HVACs in a roughly equivalent way using part load curves. I am hoping that there
is a way around this. Thank you very much for your help. __._,_.___ Posted by: "Edward G. Lyon" <EGLyon@xxxxxxx> EnergyPlus support is found at: http://energyplus.helpserve.com or send a message to energyplus-support@xxxxxxxx The EnergyPlus web site is found at: http://www.energyplus.net/ The group web site is: http://groups.yahoo.com/group/EnergyPlus_Support/ Attachments are currently allowed but be mindful that not everyone has a high speed connection. Limit attachments to small files. EnergyPlus Documentation is searchable. Open EPlusMainMenu.pdf under the Documentation link and press the "search" button. __,_._,___ |