I have come across this and it is possible to deal with some of these issues with advanced EMS. Use the HeatExchanger:AirtoAir:SensibleAndLatent model with supply outlet temperature control. Then modulate the outlet setpoint using EMS to engage the HX or not. Then use EMS actuator to modify the “Fan Pressure Rise” control when bypassing the HX.
From: EnergyPlus_Support@xxxxxxxxxxxxxxx [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx] On Behalf Of Jean marais
Sent: Thursday, July 11, 2013 11:38 PM
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Subject: [EnergyPlus_Support] Heat recovery device recovers heat when off
v7.2
Dear Collegues,
For the second time a client is asking me why the heat recovery device is recovering heat when the availibility schedule for the object is indeed scheduled off.
I have looked at the file and it is true.
1) co-insidently, I believe a plate air air heat recovery devise should not have an availibility schedule...the air must pass through the devise unless it is bypassed. Bypass at the moment, is possible only when used together with economizer control switched on. This also works to stop the heat exchanger exchanging heat as it is bypassed when within economizer limits. However, in practise, the bypass is normally on the exhaust stream AND a very significant energy reduction from the normal fan operation is expected, due to the significant pressure reduction when the air does not battle its way through the heat exchanger. Equipment data sheets also have this info to input. I would like the plate model (and possibly generally all heat recovery air devices) to
a) be reworked either eliminating the availibility schedule or making it effective AND updating the documentation
b) include inputs for pressure reductions when in bypass operation AND to be reflected as a saving in the reports AND to possibly include a seperate controller that may or may not couple with the oda damper controller
2) has anyone else come across this issue? Is it restrict
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