ASHRAE 90.1 - Few Questions

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Dear all,

I have a few questions regarding ASHRAE 90.1 compliance and I really
hope someone can answer me :-)

My project is a school, and I'm using system 7 (VAV with reheat)

1. "G3.1.2.4 Fan System Operation. Supply and return fans shall
operate continuously whenever spaces are occupied and shall be cycled to
meet heating and cooling loads during unoccupied hours."

I understand that I should turn on the "Night Cycle" feature of the
fans. Is this enough?

2. "G3.1.2.8 Design Air Flow Rates. System design supply air flow
rates for the baseline bldg design shall be used on a supply
air-to-room-air temperature difference of 20F"

My interpretation is that if I have the set point temperature for a zone
to be 70F, I input the "Zone entering minimum supply temp" to 50F. Is
this correct? Does this mean that I should leave eQUEST to determine the
supply flow rates, and only enter the design supply flow rates in the
proposed scenario?

3. "G3.1.3.11 Heat Rejection. "...The tower shall be controlled to
maintain a 70F leaving water temp where weather permits, floating up to
leaving water temperature at design conditions."

Someone mentioned to me to go to the condenser water loop, controls tab,
and select Load Reset, with the Setpoint Temp 70F. Is this correct?

4. "G3.1.3.12 Supply Air Temp. Reset. Supply air temp shall be
reset based on zone demand from the design temp difference to a 10F temp
difference under minimum load conditions.

Can someone please explain how can I accomplish this?

5. "VAV Minimum Flow Setpoints. Minimum volume setpoints for VAV
reheat boxes shall be 0.4cfm/ft2 of floor area served

What do they mean by this? Where can I enter it?

Thank you all for your continuous support! Without you I wouldn't have
reached this final stage of my project!

Many thanks,

Omar Katanan

Omar Katanani's picture
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Joined: 2011-09-30
Reputation: 0

Dear all,

I have a few questions regarding ASHRAE 90.1 compliance and I really
hope someone can answer me :-)

My project is a school, and I'm using system 7 (VAV with reheat)

1. "G3.1.2.4 Fan System Operation. Supply and return fans shall
operate continuously whenever spaces are occupied and shall be cycled to
meet heating and cooling loads during unoccupied hours."

I understand that I should turn on the "Night Cycle" feature of the
fans. Is this enough?

2. "G3.1.2.8 Design Air Flow Rates. System design supply air flow
rates for the baseline bldg design shall be used on a supply
air-to-room-air temperature difference of 20F"

My interpretation is that if I have the set point temperature for a zone
to be 70F, I input the "Zone entering minimum supply temp" to 50F. Is
this correct? Does this mean that I should leave eQUEST to determine the
supply flow rates, and only enter the design supply flow rates in the
proposed scenario?

3. "G3.1.3.11 Heat Rejection. "...The tower shall be controlled to
maintain a 70F leaving water temp where weather permits, floating up to
leaving water temperature at design conditions."

Someone mentioned to me to go to the condenser water loop, controls tab,
and select Load Reset, with the Setpoint Temp 70F. Is this correct?

4. "G3.1.3.12 Supply Air Temp. Reset. Supply air temp shall be
reset based on zone demand from the design temp difference to a 10F temp
difference under minimum load conditions.

Can someone please explain how can I accomplish this?

5. "VAV Minimum Flow Setpoints. Minimum volume setpoints for VAV
reheat boxes shall be 0.4cfm/ft2 of floor area served

What do they mean by this? Where can I enter it?

Thank you all for your continuous support! Without you I wouldn't have
reached this final stage of my project!

Many thanks,

Omar Katanani

Omar Katanani's picture
Offline
Joined: 2011-09-30
Reputation: 0