RFI Update 10-7-26.pdf

TECHNICAL QUESTIONS AND SOLICITATION #: 36C77626R0104

RESPONSES TRACKING SHEET PROJECT TITLE:

502-21-222 EHRM Infrastructure Upgrades

Pineville, LA

# CONTRACTOR QUESTION VA RESPONSE

194 Building 45 is presently out of service, and it is our understanding that this is because of mold concerns within the building. Can you confirm what measures should be taken to address mold under this project?

Assume for bidding purposes that mold will be present but not disturbed over the course of the work. Contractor is required to wear appropriate PPE during installation work.

99 C-304-Note #8-contractor shall bore or tunnel under existing structure to install new duct bank at Bldg #13. We cannot find the profile at Bldg#13.

Contractor shall assume, for bidding purposes, that directional drilling for this run shall be at a depth no greater than six (6) feet below grade.

151 225-Foot Refrigerant Piping Requirement: MP601 states, “Allowable refrigerant piping length shall be a minimum of 225 feet.” Please confirm the intent is that the selected equipment must be capable of an allowable refrigerant piping length of at least 225 feet, and not that each installed line set is required to be a minimum of 225 feet. Also confirm equivalent-length and vertical-lift limitations are to be based on the selected manufacturer's requirements.

As a follow up question, does the basis of design equipment meet this requirement?

Confirmed. The note refers to the allowable refrigerant piping length of the selected equipment; it does not require each installed line set to be a minimum of 225 feet. Line sets shall be installed at the lengths required by the actual routing. Equivalent length, vertical lift (height difference), and number-of-bends limitations shall be per the selected manufacturer's published requirements. The revised basis of design (Mitsubishi P-Series, R-454B) has a maximum allowable piping length of 165 feet and a maximum height difference of 100 feet; installed piping shall not exceed the selected manufacturer's limits.

158 The HVAC units scheduled call for 410 A refrigerant, however this has been phased out and is no longer available. Units with the new 454 refrigerant do not fit the design layout and in all cases require a separate additional power circuit to the indoor units. The design assumed the units would be powered form the outdoor units by a power/com wire. Will the VA please provide an updated selection for these units?

The basis of design is revised to the Mitsubishi P-Series R-454B wall-mounted split systems: PKA-AK36NL indoor / PUZ-AK36NL outdoor (3-ton) and PKA-AK24NL indoor / PUZ-AH24NL outdoor (2-ton).

These indoor units are powered from the outdoor unit through the indoor-outdoor interconnect (S1-S2, 208/230V), so a separate power circuit to the indoor units is not required. 2-ton units remain on the 2-pole 30A, 208V circuits shown on the plans. All 3-ton units shall be a 2-pole 50A, 208V breaker with (3) #8 AWG and (1) #10 AWG equipment ground in 1" conduit.

# CONTRACTOR QUESTION VA RESPONSE

159 Daikin is listed as the basis of design for the mini split units. They have advised that they no longer produce a 3-ton indoor ceiling suspended model. They advised installing two (2) 1 ½ ton wall mount units. Due to the 225 ft line set required, these will also require power at the interior unit. Will the VA please confirm an updated model number or alternate solution for these mini-split units?

Provide one (1) Mitsubishi PCA-AK36NL 3-ton ceiling-suspended indoor unit with PUY-AK36NL outdoor unit in lieu of the Daikin 3-ton ceiling-suspended unit. Two (2) 1-1/2-ton wall-mounted units are not required. Power this unit from a 2-pole 50A, 208V breaker with (3) #8 AWG and (1) #10 AWG equipment ground in 1" conduit.