Hello All:
It is my understanding from reading the DOE2.2 Vol.3 Topic Manual that the system type "IU" - induction unit - can be used to simulate an active chilled beam system, without creating a separate eQuest DOA system. How have you or others gone about configuring such a system? I'd appreciate knowing your cautions/recommendations.
Other eQuest email threads have indicated that the heat from zone EA/RA streams is not recognized by a DOAS's energy recovery device when using a dual system configuration, DOAS & OA-FROM-SYSTEM. And that an exceptional calculation would be needed to justify such heat recovery. In the interest of capturing exhaust air heat, it seems logical to use the system side parameters for the OA unit and the sub-zone heating/cooling capacities for the chilled beams. What then would be the advantage of creating two systems (DOAS & OA-FROM-SYSTEM)?
Instead of creating a separate eQuest system for a 100% OA system, I am attempting to use the IU system configuration to simulate an active chilled beam system with 100%OA and capture the EA stream heat with an enthalpy wheel component assignment. Please see the below BDL input and hourly report of the enthalpy wheel heat recovery.
Thanks in advance for any recommendations,
Jonathan R. Smith AIA LEED?AP
BDL input: Typical system /sub-zone
..
"ERV-1 (IU)" = SYSTEM
TYPE = IU
HEAT-SOURCE = HOT-WATER
BASEBOARD-SOURCE = HOT-WATER
RETURN-AIR-PATH = DUCT
MAX-SUPPLY-T = 72
HEAT-SET-T = 72
MIN-SUPPLY-T = 55
MAX-HUMIDITY = 55
ECONO-LIMIT-T = 65
ECONO-LOW-LIMIT = 45
SUPPLY-FLOW = 6020
RETURN-FLOW = 6020
MIN-OUTSIDE-AIR = 1
MIN-AIR-SCH = "S1 Sys1 (FC) MinOA Sch"
OA-CONTROL = FIXED
RECOVER-EXHAUST = YES
FAN-SCHEDULE = "S1 Sys1 (FC) Fan Sch"
SUPPLY-DELTA-T = 5
SUPPLY-KW/FLOW = 0.00186
RETURN-DELTA-T = 5
RETURN-KW/FLOW = 0.00186
NIGHT-CYCLE-CTRL = CYCLE-ON-ANY
RETURN-FAN-LOC = RELIEF
INDUCTION-RATIO = 2.7
HW-VALVE-TYPE = TWO-WAY
HW-LOOP = "Hot Water Loop"
CHW-VALVE-TYPE = TWO-WAY
CHW-LOOP = "Chilled Water Loop"
BBRD-LOOP = "Hot Water Loop"
HEATING-CAPACITY = -300000
EVAP-CL-TYPE = DIRECT
DESICCANT = SOL-VENT-AIR-1
DESC-HEAT-SOURCE = GAS-HYDRONIC
ERV-RECOVER-TYPE = ENTHALPY-WHEEL
ERV-OA-FLOW = 6020
ERV-RUN-CTRL = OA-EXHAUST-DH
OA-EXHAUST-DH = 12.313
ERV-RECOVER-MODE = OA-HEAT/COOL
ERV-TEMP-CTRL = FIXED-SETPT
OA-HEAT-SETPT-T = 70
OA-COOL-SETPT-T = 80
ERV-CAP-CTRL = MODULATE-HX
..
"EL1 South Perim Zn (G.S7)" = ZONE
TYPE = CONDITIONED
MIN-FLOW-RATIO = 1
HEATING-CAPACITY = -366530
BASEBOARD-RATING = -100000
FLOW/AREA = 0.1
OA-FLOW/PER = 9
DESIGN-HEAT-T = 72
HEAT-TEMP-SCH = "S1 Sys1 (FC) Heat Sch"
DESIGN-COOL-T = 75
COOL-TEMP-SCH = "S1 Sys1 (FC) Cool Sch"
BASEBOARD-CTRL = THERMOSTATIC
SIZING-OPTION = ADJUST-LOADS
SPACE = "127 Cafeteria"
..
Hourly Report for Typical IU System:
Month
Day
Hour
Temp of air leaving heat coil - hot deck temp (deg F)
ERV Outdoor air temperature entering HX, after preheat (?F)
ERV Outdoor air temperature leaving HX (to mixed air plenum) (?F)
1
4
9
72
25
58.7408
1
4
10
72
25
59.4445
1
4
11
72
27
59.8008
1
4
12
72
29
60.6705
1
4
13
72
31
61.3672
1
4
14
72
31
61.2842
1
4
15
72
31
61.1658
1
4
16
72
31
61.1586
1
4
17
72
30
60.9037
Jonathan R. Smith AIA LEED?AP
