503-19-112 Replace Steam System Bid RFI Responses_7.19.23.pdf

PRE-BID RFI RESPONSES JULY 19, 2023

1. The pipe insulation required by Specification Section 23 07 11 is very likely much thicker than the existing insulation.

a. Have provisions been made to physically fit the new thicker pipe insulation in the same spaces as the existing?

Intent is for new piping to follow pathways of existing piping. However, routing on plans is generally diagrammatic to show design intent. Refer to specification 23 22 13 paragraph 3.1.B.

2. If the existing piping is not pitched per the specification requirements will the new piping have to be?

a. If yes, who will be responsible for utility relocations and potential ceiling height adjustments?

New piping shall be pitched per specifications. Steam may be drip-trapped and re-lifted where necessary to maintain elevation. Coordinate starting heights to stay above ceiling and allow for offsets as required to avoid interferences. Refer also to specification 23 22 13 paragraph 3.1.B. Where interferences are otherwise unavoidable without lifting condensate, relocate conflicting utilities as required. Allow in bid for up to 200 LF of electrical/data conduit relocations and 100 LF of air duct offsets as needed.

3. It appears duct modifications may be required for many existing air terminal units to tie in the new slot diffusers.

a. Are any utilities going to need to be relocated?

b. Is there physical space to fit the new ductwork?

c. Who is responsible for utility relocation?

d. What are the required duct sizes?

i. Detail indicates branch runouts are to match diffuser neck sizes; however, there are multiple branch runouts on single ducts with no size listed.

Refer to specification 23 31 00 paragraph 3.1.B. New branches serving 1 new LSD-1: 6” dia; 2 new LSD-1:

8” dia; 3 new LSD-1: 10” dia. Equivalent rectangular sizes are acceptable for new branches serving multiple diffusers. Individual 6” runouts from existing main are acceptable, as conditions allow, at contractor’s option.

4. It appears the piping is required to be replaced thru the existing ceilings.

a. Who is responsible for any utilities/equipment that must be relocated for this work to take place?

Refer to question 2

5. Previous experience tells us there will be existing steam valves that will not close properly.

a. Who is responsible for replacing non-functional existing valves?

Intent is to replace existing steam system including valves.

6. Previous experience tells us hot water radiant ceiling panels provide less heat than the existing steam radiators.

a. Who is responsible if spaces are not able to maintain the appropriate temperature upon project completion?

Radiant panels are supplemental to the VAV heat which was added after the original existing steam radiators.

7. What capacity is required for each radiant ceiling panel?

Radiant panels shall provide minimum 230 BTU/H per SF at a mean water temperature of 190°F.

8. Sheet GC001:

a. Phasing Schedule does not allow much work to be accomplished during each shift with ceilings having to be removed and utilities relocated to start work and then the space having to be returned to previous occupied conditions by the end of the shift.

i. Has this been considered in the Period of Performance?

VA to confirm.

ii. Are any occupants able to be relocated to allow areas to become construction sites for more than just 8-15 hour, or weekend shifts?

VA to confirm.

b. Phasing General Note I - Which two weeks of the year will the JCAHO inspection be?

VA to confirm.

c. Sterilizer maximum allowable downtime is only 4 hours.

i. Is there a limit on the number of times the sterilizers can be down for 4 hours?

VA to confirm.

ii. Can sterilizer equipment data be provided to determine cost for rental clean steam generator?

There are two large sterilizers “Steris Amsco Century V-148H Prevac Steam Sterilizer” and two washer/disinfectors “Steris Reliance Genfore”. The washer/disinfectors, though not shown on current plans, are located on the plan west wall of room 3E04 and must be reconnected to the new steam and condensate mains shown to the large sterilizers.

9. Sheet GC101:

a. MEDIUM PRESSURE STEAM BASEMENT MAIN PIPING PHASING PLAN – Requires a new parallel 6” MPS main be installed adjacent to the existing.

i. Is there physical space to install this main?

1. Sheet MP103 – Shows new 6” MPS, 4” LPS & 4” PC in the same location as many 3”, 4”, 5” & 6” existing to remain pipes.

a. Is there physical space for the new piping?

ii. Who is responsible for any equipment or utilities that may have to be relocated?

New pipes were intended to follow pathways of demo’d pipes (3, 4, 5, 6” pipes noted are not existing to remain). Refer to previous RFI responses regarding field adjustments and offsets as required to achieve general layout intent.

10. Sheet MD601:

a. Keynote 2 indicates steam radiator digital valve controls are to be migrated to the new hydronic radiant ceiling panels.

i. Do the existing valves have the proper Cv to appropriately control the new radiant ceiling panels?

The control I/O point is to be migrated, the physical controls (valve, wiring, conduit) are to be new per plan notes. Below keynote is typical for new radiant ceiling panels.

11. Sheet MP303:

a. There is an “X” on the 4” dia MPS (tagged “MSV”) line to the domestic water heaters.

i. Does this “X” symbol represent a pipe anchor?

Yes

ii. Is an anchor required for the 6” MSV line?

Floor penetration serves as an anchor in this plane.

iii. If this is an anchor, locations shown on plan will not work with the distances on the expansion loop detail.

1. Where are the guides to be installed?

Refer to detail 11 on M-502 and general note 3 therein.

iv. There are other “X”s throughout the plans.

1. Are anchors required at each location?

Refer to symbols legend

v. Can a plan be provided with anchor locations identified?

Anchor locations are indicated per the symbols legend

b. Is “MLPS” low pressure steam?

Refer to HVAC piping symbols on M-002

12. Sheet MP112:

a. The new pipes up thru the bldg are larger than existing.

i. Will the equipment function properly if deduct alternate 1 is accepted?

Equipment will function as existing.

b. Keynote 4 indicates “TYP 5”

i. There appears to only be 4 pipes. Are we missing one?

4 is correct.

13. On GC101 Main piping phasing plan, to maintain steam while installing new line the branch connections are they the 6” mains only?

Question is not clear

14. The piping tagged MSV would that piping fall under medium pressure steam or vent piping. On drawing MP303 the 4” MSV is suppling medium pressure steam to the existing domestic water heaters and is not vent piping. The 5” MSV piping is from the SV. Do you want this piping galvanized as stated in specifications.

MSV is steam vent piping. The 4” MSV on MP303 is venting the condensate pump receiver in BB12 from the south and pump receiver in BE01F from the north and then rising between the water heaters through the chase to the roof. Follow steam vent specifications.