630A4-26-401 MRI AHU Modification

36C24226R0060 Amendment 5 630A4-26-401 MRI AHU Modification 8. Question -Hallway Fan Coil Units-The contract documents indicate (6) 18,000 BTU/h chilled water surface-mounted fan coil units in the hallway. We have concerns with this configuration: the surface-mounted units would protrude into the corridor, presenting both an aesthetic issue and a potential head-strike hazard for pedestrians. We propose substituting ceiling-mounted fan coil units in lieu of the surface-mounted units. Please advise which of the following options is acceptable:

VA Response: Option A would be acceptable if there is no additional cost to the VA. Six ceiling mounted units would provide both the desired level of equipment redundancy and distributed air flow equivalent to the contract design wall mounted units. An 18,000 btu wall mounted evaporator fan unit requires a minimum of 6 inches of clearance below the ceiling for proper air flow. As the evaporator fan coil unit is approximately 12-14 inches high, in an 8 foot high corridor (96 inches clear), there would be a minimum of 76 inches clearance under the evaporator fan unit, or 6 foot 3 inches. If the corridor is higher than 8 feet then the clearance would increase.

Option A: Provide (6) ceiling-mounted fan coil units at 18,000 BTU/h each; note that due to ceiling constraints, the units cannot be equally spaced along the corridor.

Option B: Provide (3) ceiling-mounted fan coil units of higher capacity, sized to provide equivalent total cooling capacity, spaced evenly along the corridor.