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Inputing C-factor in eQuest

I'm modeling an apartment building that has toilet and bathroom exhaust and no mechanical supply for the apartments. Make-up air comes from trickle vents.

I have been thinking about the best way to do this, that is whether:

  • I should assign this to a zonal exhaust fan (EXHAUST-FLOW), or
  • I should specify the CFM exhausted as an outdoor air flow (OUTSIDE-AIR-FLOW).

I think the OUTSIDE-AIR-FLOW would be the least problematic if I only had to deal with the baseline, but in my proposed building I only have baseboards for heating, so this wouldn't work.

First, am I correct in the above statements?

Second, if I do specify an exhaust fan in the following way: FAN-CONTROL = CONSTANT-VOLUME EXHAUST-FLOW = 50 EXHAUST-FAN-SCH = "Fraction Always 1 Yr" EXHAUST-SOURCE = INFILTRATION

  • Will eQuest actually take into account that 50 CFM of outside air should be added (through infiltration) as a load?
  • Will eQuest also take that into account for the sizing of my zonal equipment?
  • Finally, will it interact in any way with the infiltration defined under Internal Loads for the Space?

Inputing C-factor in eQuestHow do you model exhaust fans in eQuest?

I'm modeling an apartment building that has toilet and bathroom exhaust and no mechanical supply for the apartments. Make-up air comes from trickle vents.

I have been thinking about the best way to do this, that is whether:

  • I should assign this to a zonal exhaust fan (EXHAUST-FLOW), or
  • I should specify the CFM exhausted as an outdoor air flow (OUTSIDE-AIR-FLOW).

I think the OUTSIDE-AIR-FLOW would be the least problematic if I only had to deal with the baseline, but in my proposed building I only have baseboards for heating, so this wouldn't work.

First, am I correct in the above statements?

Second, if I do specify an exhaust fan in the following way: FAN-CONTROL = CONSTANT-VOLUME EXHAUST-FLOW = 50 EXHAUST-FAN-SCH = "Fraction Always 1 Yr" EXHAUST-SOURCE = INFILTRATION

  • Will eQuest actually take into account that 50 CFM of outside air should be added (through infiltration) as a load?
  • Will eQuest also take that into account for the sizing of my zonal equipment?
  • Finally, will it interact in any way with the infiltration defined under Internal Loads for the Space?

How do you model exhaust fans in eQuest?

I'm modeling an apartment building that has toilet and bathroom exhaust and no mechanical supply for the apartments. Make-up air comes from trickle vents.

I have been thinking about the best way to do this, that is whether:

  • I should assign this to a zonal exhaust fan (EXHAUST-FLOW), or
  • I should specify the CFM exhausted as an outdoor air flow (OUTSIDE-AIR-FLOW).

I think the OUTSIDE-AIR-FLOW would be the least problematic if I only had to deal with the baseline, but in my proposed building I only have baseboards for heating, so this wouldn't work.

First, am I correct in the above statements?

Second, if I do specify an exhaust fan in the following way: FAN-CONTROL = CONSTANT-VOLUME EXHAUST-FLOW = 50 EXHAUST-FAN-SCH = "Fraction Always 1 Yr" EXHAUST-SOURCE = INFILTRATION

  • Will eQuest actually take into account that 50 CFM of outside air should be added (through infiltration) as a load?
  • Will eQuest also take that into account for the sizing of my zonal equipment?
  • Finally, will it interact in any way with the infiltration defined under Internal Loads for the Space?