12405B22R0014-Amendment 02 - Questions and Answers.pdf

12405B22R0014 – Amendment 02 - Questions and Answers

1. Is each room/Lab the units are serving operating to satisfactory room temps and humidity levels? Each room operating at the same inside temperature (72-73 F) and humidity levels around 50% - 55% to both units.

2. Will the replacement AHU’s utilize the current piping and ductwork in their current locations?

Yes, use same piping and ductwork.

a. Please provide current header sizes for each supply and return lines for each coil.

Header supply and return 2” and 1” line.

3. The “Statement of Work” mentioned 2 filter sizes, 2” MERV 8 & 4” MERV 13, for the replacement AHU’s. Current AHU’s have installed 2” MERV 8 & 12” rigid cartridge filters. Please confirm the 4” MERV 13 will be sufficient filtration for the room being served. AHU #9: Pre- 24x24*2 Final- 24x24x12(one inch lip); AHU #10: Pre 1-12x24x2, 1-24x24x2 Final- 12x24x12, 24x24x12 (one inch lip)

4. During the site visit it was noticed the water piping serving each AHU was ran in series from the Post cool coil to the pre cool coil. Please provide those water temps and GPM’s listed above to fully understand how the units need to operate without change to current set up. Chilled water temp is at 45 F 63 gpm.

5. Typically, Labs are required to operate at specific humidly levels. How are the current units controlling this? Dehumidify at 55%.

6. The current units are approximately 20 years old. Over the years ASHRAE design conditions have steadily increased for EAT of outside air. Has this been accounted for in the current or replacement units? Upgrade to current standards due to units age.

7. Replacement AHU’s can be designed with NTM double wall aluminum doors with windows and marine lights in airside service locations. Is this a feature that service would like for us to incorporate? Both AHU are small units, no need for double wall aluminum doors and marine lights inside service locations.

8. What is the current electrical load for AHU 9 (480VAC 25A 3 phase) and 10 (481VAC 20A 3 phase).

a. Will replacement AHU’s be required to operate at the same load? Same load capacity