PRE-PROPOSAL RFI RESONSES 657-27-107.pdf

657-27-107JC FCA - Replace Select Hot Water Heating Systems, JC Pre-Bid RFIs

Replace Select Hot Water Generating System Solicitation 36C25526R0166

Project 657-27-107JC Pre-Bid RFI’S

1. The attachment labeled “ATTACHMENT SPECIFICATIONS 36C25526R0166_1” does not contain the specifications. This looks to be the Design Manual. Please provide specifications for the project.

SEE ATTACHED

2. Statement of Work, Note 2, Bullet Point #5 states “Integrate controls, instrumentation, electrical wiring, and safety devices.” Please provide more details as to what will be required for “Controls”.

Automatic Controls Equipment Systems performs the control work at John Cochran. Should we reach out to Mike Kunstel @ (314) 603-2755 for more information? YES

3. The existing heat exchangers have integrated pumps build onto their “skids”. Will the new replacement exchangers require the same integration? YES. REMOVE & REPLACE ONE FOR ONE

4. Should the contractor plan on piping to the existing shutoff valves? YES

5. What is the steam pressure in the mechanical room? Will a PRV be needed? The steam pressure in the mechanical room is medium pressure, and the pressure is between 40 and 50 psi. A PRV will be needed.

6. Are Taxes to be included in the project? YES

7. Are equipment pads required for the new equipment? YES, please provide 4-inch concrete pad to all 4 Hot water generators.

8. Should the contractor plan on 2” fiberglass insulation for the piping? YES

9. What is the required leaving water temperature? 140 degree Fahrenheit. Please see the screenshot below

10. Can you Verify that this project home page is correct for the right NAISC Code 238220 Plumbing, Heating and Air-Conditioning Contractors? Yes

11. Design Manual as the project specification (Ref: CO email of 9/21/2026; Design Manual attachment (Vol. 2, Water Boilers, 7/1/2026)) On September 21, 2026 the Contracting Officer advised that the Design Manual serves as the project specification. The Manual is written for heating hot water boiler plants (burners, fuel systems, stacks, combustion air, dual fuel and N+1 plant capacity), while this project replaces four domestic hot water generators. Please identify which Design Manual sections the VA will enforce for this work, for example 2.3 (non-proprietary equipment), 6.1.3 (double-wall heat exchangers), 6.6.6 (expansion tanks), 11.1.3 and 11.4 (controls and BAS monitoring), 12.2 (testing and commissioning plan) and

12.3.3 (piping flushing). Please also confirm that the boiler-plant provisions (fuel, burners, stacks, combustion air, emergency generators and plant N+1 capacity) do not apply.

For domestic hot water (DHW) generators serving potable water, the governing document is the

Plumbing Design Manual (PG-18-10). It is attached here for ease of use. Enforce the following sections:

• Non-proprietary selection: Use non-proprietary equipment; specify salient characteristics and allow VA-approved equals.

• Double-wall heat exchangers: Required for DHW when using indirect steam or hot-water sources; follow IPC and PG-18-10 §4.2.

• Controls and BAS/ECC monitoring: Provide local gauges and BAS points; analog plus digital sensors are required, on emergency power (PG-18-10 §4.7.2).

12. Required capacity and performance (Ref: SOW §2; Drawing 01-ME-001 notes) The SOW and drawing give the capacity as "45 gallons" per generator. The existing units are AERCO B-Plus water heaters that appear to be steam-fired (heat exchanger nameplate dated 1990). Please state whether "45 gallons" refers to storage volume, output in GPM or a model designation. Please also provide the required performance for each new unit: flow rate (GPM) at the design temperature rise, entering and leaving water temperatures, and the steam supply pressure available at the units.

• The system must deliver 60 °C (140 °F) discharge, maintain a recirculating return ≥ 51.1 °C

(124 °F), and meet fixture delivery limits via point-of-use/ASSE valves (e.g., showers per ASSE 1016;

sinks per ASSE 1070). (PG-18-10 §4.2, §4.2.7)

• Provide thermal eradication capability: raise DHW to 170–180 °F at a reduced flow of ~30 gpm for system sanitization; include bypasses/mixing valve provisions. (PG-18-10 §4.2.3.1–.2; §4.5.5.1)

• Steam supply pressure (to steam-fired HX): Contractor shall field-verify plant steam conditions and size PRV/control packages accordingly; VA will provide plant data during submittals.

• “45 gallons” Treat any “45-gal” notation as storage capacity

13. Design responsibility and existing-condition data (Ref: Drawings 01-GI-001 and 01-ME-001) The drawings include no equipment schedule, piping design or layout for the new units. Is the contractor responsible for selecting, sizing and laying out the replacement equipment and piping (design-build)? If so, are PE-stamped submittals required? If not, will the VA issue a basis-of-design equipment schedule and details by amendment? Please also provide any record drawings or equipment data the VA has for the existing installation.

Please remove and replace 4 water generators and associated accessories. Plan on piping to the existing shutoff valves. Contractor is responsible for selection & layout of the hot water generators.

14. System served and equipment type (Ref: CLIN 0001; SOW; Design Manual 2.3 and 6.1.3) CLIN 0001 describes the units as "domestic hot water generators for heating." Please confirm that the four units serve the potable domestic hot water system (not space-heating hot water), that the replacements are to be steam-fired like the existing units, and that double-wall heat exchangers (Design Manual 6.1.3) are required. Please also confirm that equipment from any manufacturer meeting the salient characteristics is acceptable (Design Manual 2.3).

• Potable domestic hot water system — not space-heating. (Scope of PG-18-10

• Energy source: With a central plant present, PG-18-10 prefers indirect steam/hot water sources

(semi/instantaneous HX for DHW). (PG-18-10 §4.2.2)

• Double-wall HX: Required by IPC/PG-18-10 for potable DHW. (PG-18-10 §4.2)

• Non-proprietary equipment acceptable when meeting salient characteristics (Steam Manual §2.3;

principle applied here).

15. Ancillary equipment: replace or reuse (Ref: SOW §4 ("associated ancillary equipment")) Please identify which existing ancillary equipment is to be replaced and which is to be reused. This includes the steam pressure-reducing valve station, the steam traps, the condensate return unit (Domestic Pump CC Series, Model 154CC, seen at the site visit), expansion tanks, thermostatic mixing valves and hot water recirculation pumps.

Limit the scope of work up to the shut-off valve and use the following acceptance criteria based on

PG-18-10:

• Steam PRV station: Provide/verify PRV capacity and controls to meet DHW HX design

(PG-18-10 §4.11). Replace if existing cannot meet load, turndown, or control stability; include monitoring ports.

• Steam traps & condensate unit: Must match new HX load/pressure regime; replace or reconfigure if altered duty requires. Coordinate per plant/steam practices; retain if capacity and condition meet design. (Referenced as ancillary to the indirect HX arrangement.)

• Expansion tanks: Provide DHW expansion tanks sized and scheduled in design documents;

replace if existing does not meet new duty. (Appendix C equipment schedules)

• Thermostatic mixing valves: Required (ASSE 1017 for master; ASSE 1016/1070 at points of use), sized/located per PG-18-10 §4.2.7; replace legacy controls to meet temperature and thermal eradication needs.

• Hot-water recirculation pumps: Required in patient-care buildings; provide redundant lead/lag pumps and balancing per PG-18-10 §4.2.8–4.2.9; replace legacy pumps if they cannot meet velocity/temperature loss limits

16. Controls and BAS integration (Ref: SOW §2; Design Manual 11.1.3 and 11.4) Must the new generators be connected to the facility BAS/ECC? If so, which BAS platform and vendor serve Building 1, and which points are to be monitored? The existing AERCO controls use solenoid valves and a temperature switch, and the panel diagram also shows a control-air solenoid.

May the new units use electronic controls and actuators, and will control air remain available at this location?

• Required: Provide BAS/ECC integration and local instrumentation; analog and digital sensors on emergency power (PG-18-10 §4.7.2).

• Typical monitored points (per PG-18-10 and Legionella controls):

• DHW discharge temperature at HX outlet; high-temp alarm (+5 °F above 140 °F) for mixing valve failure.

• Recirc return temperature at end of loop; pump run/lead-lag status; alarms.

• Flow (recirc), local pressure/temperature test ports, and sampling points.

• If supplemental disinfection is used, oxidant residual sampling points and alarms. (PG-18-10

§4.5.1–4.5.4)

• Controls/actuators: Electronic controls and actuators are acceptable (non-proprietary).

“Control air” is not required by PG-18-10 and may be eliminated; design for electronic control

17. Hazardous materials (Ref: SOW §4; existing equipment and piping insulation)

(a) Does the VA have an asbestos and lead survey for Mechanical Room B001 and the piping and equipment to be disturbed? If so, please provide it. If not, should offerors include a survey and abatement in their price, or will suspect materials be handled by the VA or by contract modification if they are encountered? (b) If abatement is required, please confirm whether the contractor is to provide the VA Professional Industrial Hygienist (VPIH) for air monitoring and clearance. If the VA will provide the VPIH, please identify the firm so offerors can price its requirements.

The VA does not expect any HAZMAT in mechanical room B001.

18. Seismic restraint (Ref: Design Manual 2.2.5) Please confirm whether engineered seismic restraint of the new generators and piping, with PE-stamped calculations per Master Specification 13 05 41 and H-18-8, is required for this project.

Yes. Engineer and PE-stamp seismic restraint and calculations for DHW generators/piping per VA

H-18-8; use current VA Master Spec 13 05 31 Seismic Restraint Requirements (facility standard) for hardware and details. (PG-18-10 §2.7; spec references)

19. Emergency power (Ref: SOW §2 (electrical wiring)) Are the existing generators' power and control circuits fed from the facility's essential electrical system? Should the new units be connected to emergency power?

Yes. DHW heating equipment controls, monitors, and (in patient-care buildings) booster/recirculation pumps and meters shall be on emergency power per PG-18-10 §§4.2.3, 4.7.2, and 4.12.2(f).

20. Salvage (Ref: SOW §4) Does the VA want to keep any of the removed equipment or components? Or does all removed material become the contractor's property for recycling or disposal?

The VA does not want to keep any of the removed equipment or components

21. B. Location, Sequencing and Schedule

Room location (Ref: CLIN 0001; Drawing 01-ME-001) CLIN 0001 locates the work in Room B018-01-JC. Drawing 01-ME-001 locates it in Room B001-01- JC, in the sub-basement of Building 1. Please confirm the correct room.

The work is located in Room B001-01-JC, in the sub-basement of Building 1.

22. New unit locations and sequencing (Ref: SOW §2–§4; Drawing 01-ME-001) The SOW requires all four new generators to be installed and commissioned before the four existing units are removed, but Drawing 01-ME-001 shows no locations for the new units. Please identify where the new units are to be installed. Alternatively, may the contractor phase the work? That is:

remove out-of-service Generators 1 and 2, install and commission two new units in their place, then replace Generators 3 and 4, keeping domestic hot water service in operation throughout.

The contractor can phase the work. That is: remove out-of-service Generators 1 and 2, install and commission two new units in their place, then replace Generators 3 and 4, keeping domestic hot water service in operation throughout.

23. Working hours, shutdowns and temporary hot water (Ref: SOW §1; Security Requirements) Please state the normal working hours and the allowable steam and domestic hot water shutdown windows (duration, days and times, and notice required). Must tie-ins be performed after hours? If so, the Security Requirements call for a VA-employee escort. Will the VA provide escorts at no cost to the contractor? If temporary domestic hot water is needed during tie-ins, is that the contractor's responsibility?

• The normal working hours is from 08:00 am to 4:30 PM.

• Any shutdown should be requested 21 calendar days in advance

• Yes, must tie-ins be performed after hours. The VA will provide escorts at no cost to the contractor.

• The contractor is not required to provide temporary domestic hot water during tie-ins.

24. Access, rigging, staging and parking (Ref: SOW §2) Please identify the approved route and any restrictions for moving equipment to and from the sub-basement (freight elevator availability and capacity, door and hatch openings, floor loading). Please also designate contractor staging/laydown and parking areas.

• The VA does not provide any staging/laydown and parking areas

• The loading dock can be used

• The freight elevator has a capacity of 5,000 LB & can be used.