GWR Engineering, P.C. Consulting Engineers

GWR Engineering, P.C. Consulting Engineers

130 Quarter Mile Rd Charlotte, VT 05445 Tel: (802) 425-2825 [email protected]

USGBC LEED Accredited & ASHRAE High-Performance Building Design Certified Professional

CHAMPLAIN VALLEY UNION HIGH SCHOOL

ADMINISTRATION ERU SCOPE OF WORK MARCH 31, 2021

The following describes the scope of work and installation details for ADDING AN ERU TO THE OUTSIDE AIR SERVING ADMINISTRATION AHU. PROJECT OBJECTIVE SUMMARY & INFORMATION: The CHAMPLAIN VALLEY UNION SCHOOL, looking to increase energy efficiency and improve IAQ, desires to add Energy Recovery to the existing Administration HVAC AHU. This scope of work addresses specific system installations to achieve this result. The existing AHU is a 1993 installation. Controls were upgraded in 2004 with building renovations and then again in 2016, operating on the current school’s FMCS (by TCV). This is a 2500‐cfm supply and return ducted system with fixed OA ducted (12x8) to the return of the unit duct system. An existing MOD opens and closes base on occupancy scheduling for the unit. The owner desires to add an ERU with approximately 500 cfm capacity to achieve 20% OA for the Administration areas served. This new unit would reuse existing OA duct, detaching it from the current AHU RA connection and extending it for OA connection to ERU. Fresh Air from the ERU (tempered thru core) would be fed back into the Admin AHU Return Air duct (as OA was before). A new tap from the existing AHU RA would be required to feed RA to the ERU and a new EA duct will need to be installed, connecting to existing EA duct (for larger AHU) near exterior louver connection (25 feet east). The proposed unit’s size was selected to fit up through the pulldown stair access to this space on the upper level. Unit would be floor mounted on isolation pads. Power from existing panel “MP” in office directly below space will be required for the new ERU. New ERU would operate on current schedule used by Admin AHU for occupancy and reuse the existing OA MOD (add MOD for EA).

CVUHS ADMIN ERU -- March 31, 2021 Page 2


SCOPE OF WORK SUMMARY:

Furnish & install NEW ERU (as specified below). Field verify best location for ductwork configuration. There are 2 options for unit location that provide adequate accessibility. Final location can be at the discretion of the contractor to best suit their duct run priorities. Connect OA to existing OA, bypassing existing unit connection. Install new ductwork for ERU RA, EA & SA. See details below.

Access for existing ductwork is in open space as shown in the photo on the cover of this document. Field coordination for new DUCTWORK, ELECTRICAL WIRING AND CONTROLS will be required. No detailed duct or electrical plans will be provided by GWR, only conceptual pathways based on 2004 plans and site photos contained in this document. Bids shall include all work for a completely installation with new and reconnected duct, controls and wiring system.

Insulate new EA ductwork from ERU to exterior wall. Insulate ALL OA ductwork; new extended to ERU and existing 12x8 back to louver (Approximately 25’). RA & SA ductwork does not require insulation. All new ductwork to be sealed airtight. Seal ductwork before insulation.

ONLY TCV IS ALLOWED FOR CONTROL WORK ON THIS PROJECT. Their work will be directly to CVUHS and not part of the mechanical scope of work (except coordination as required and installation of EA MOD) REUSE – EXTEND AHU controls to accommodate new ERU controls and functions where practicable and possible. Reuse controllers as appropriate, add new as required for new unit and sequence of operation. Some temperature sensing is added. All new points to be set up on FMCS graphics with trending capabilities; modify existing ADMIN AHU graphics adding new equipment and control points. Provide ADD ALTERNATE 2 TO ADD NEW AFS for measuring OA & EA as part of controls for new unit. TAB shall measure and verify accuracy.

Furnish and install new electrical power wiring for the new ERU. Integral disconnect will be provided with new ERU. Unit to be tied into Admin AHU duct smoke shut down, to mimic AHU.

This unit will not require condensate drainage.

Start‐up units and complete startup documentation.

TAB for air flow profiles (+unit profile) of the ERU and all AHU OA/RA/SA & AHU PROFILE DATA. AHU results to be evaluated by GWR to determine extent of possible unit changes to achieve or exceed the total 2500 cfm (to 2004 design values) – or IF needed. ADD ALTERNATE 1: TAB to carry BREAKOUT cost for all administration termination TAB. Refer to last 2 pages of this document for Mechanical plans of those areas to be covered. ADD ALTERNATE 2: NEW AFS for measuring and reporting OA & EA shall be installed as part of controls for new unit. TAB shall measure and verify accuracy.

Provide Commissioning support with Engineer verifying installation and operation to these contract documents.

Training & Documentation. Provide training on maintenance of new unit. Provide O&M Manuals for unit and controls. Documentation to include AS‐BUILT CONTROL Drawings and SEQUENCES OF OPERATION for equipment installed.

Warrantee the installation for 1 year from date of Cx Verification the UPGRADED system is fully functional and approved for owner turnover (ALL ISSUES LOG ITEMS CLEARED!)



DETAILED SCOPE OF WORK:

1 – BUILDING USE & SCHEDULE This work needs to be completed by AUGUST 20, 2021. Space is available for construction activity on JUNE 21, 2021 [coordinate with owner]. Work will be contained primarily to the Mechanical space above office area. There will not be any students or faculty activity in these areas during this period. Building access will be controlled by the school’s facility personnel. All work activities on site must be coordinated and approved by the school. Social distancing may still be in effect therefore multiple trades in one space MAY not be allowed. Scheduling to achieve these limitations will be required by the Mechanical Contractor, the prime bidder for this project.

The existing Administration AHU system shall be maintained in operation as much as possible during this work. Coordinate with owner on unit shutdown to perform cut in work for new ducts or other work. The AHU serving the ADMIN cannot be shutdown without notice and approval of the owner! AHU is NOT recommended to be OFF if space is occupied with more than 4 or 5 occupants for more than 2 to 3 hours, assuming all occupants immunized (COVID), all others appropriately masked.

2 ‐ DEMOLITION: Remove the connection to AHU RA of the existing 12x8 OA duct [connected to north louver]. The 12x8 duct to be continued over and down to the ERU OA connection.

VIEW LOOKING UP FROM FLOOR. ARROW POINTS SOUTH, AROUND, OVER, AND DOWN TO ERU



IT IS THE CONTRACTOR’S RESPONSIBILITY TO FULLY REVIEW THE SITE CONDITIONS BEFORE SUBMITTING THIS BID.

3 – NEW ERU INSTALLATION: Furnish & Install ONE (1) new RENEWAIRE Model # EV450IN ERU AS SPECIFIED BELOW. Location is in mechanical space on floor (below) beside the AHU, above office, options shown below.

Furnish & Install specified ERU. Provide 1” thick neoprene vibration floor mounting pads. Final location and duct routing must be reviewed and approved by GWR & the owner. Obtain approval before fabrication order. See note in photo below concerning minimizing flow resistance with duct layout.

Furnish & Install all required ductwork for ERU OA, EA, RA & SA. Flex‐connection to unit. Seal new duct joints.

2 OPTIONS FOR UNIT LOCATION SHOWN ABOVE. FLOOR MOUNT ON VIBRATION ISOLATION PADS



Cut new 12x8 or equivalent size duct into the existing RA duct approximately where shown above and run to new ERU RA connection. A VD is not anticipated to be needed in this duct run as fan speed should be able to be adjusted, as necessary. However, furnish and install one in the ductwork.

Provide new 12x8 OR 12” diameter EA ductwork from unit up & through wall EAST to connect to EA duct @ louver on east exterior wall (approx 25’ east, 12’ up). Contractor shall review site before bid and carry all necessary labor, methods and duct fittings and duct to complete this connection. Duct sealed. Install MOD provided by TCV. Locate in Mechanical space, accessible. Insulate all EA duct from ERU to louver plenum conn.. FIELD SKETCH OF DUCT AT LOUVER PLENUM SHOWN:

CIRCLED AREA APPROXIMATE LOCATION FOR CONNECTION OF 12x8 OR 12” DIA EA DUCT.



ACCESS TO THIS DUCT AREA IS THROUGH A SMALL HOLE ABOVE WHERE ERU TO BE LOCATED:

EA DUCT IS LOWER DUCT, RUNS THRU WALL AND ABOUT 25’ TO LOUVER CONNECTION. THIS IS EA DUCT FROM A DIFFERENT UNIT WITH A DIFFERENT SCHEDULE FOR OPERATION.

RUN NEW 12” DIA OR 12X8 DUCT THRU THIS WALL SO AS NOT TO BLOCK THIS ACCESS.

Reuse existing OA duct connected to AHU RA. Break duct connection just past MOD before connection to AHU RA duct. Extend OA as new duct to ERU connection; 12X8 OR 12” diameter or equal.



Furnish and install new 12” duct from ERU SA connection to AHU RA duct connection. See concept on marked up photo above.

Insulate new outside & exhaust air ducts with 2” rigid or batt. RA & ERU SA ductwork to AHU ductwork connections does not require insulation. All ductwork to be sealed air tight.

Provide power as detailed below.

Provide controls as detailed below.

ERU SPECIFICATION:



MAINTAIN UNIT MAINTENANCE CLEARANCES WHEN LOCATING AND DUCTING UNIT.

CONTRACTOR TO DETERMINE IF 12X8 FLANGES OR 10” BEST SUITS THEIR INSTALLATION. NOTE:



4 – ELECTRICAL SCOPE PROVIDE NEW 208V/ 1 PH POWER TO NEW ERU FROM PANEL “MP” LOCATED IN WALL OF OFFICE DIRECTLY BELOW UNIT LOCATION. TWO SPARE SLOTS AVAILABLE IN THIS PANEL. IDENTIFY CIRCUIT DATA AT ERU DISCONNECT WITH PERMANENT LABEL. UPDATE PANEL SCHEDULE APPROPRIATELY.

5 – NEW CONTROLS: Note: Existing building FMCS is an Automated Logic system provided by TCV. Only TCV is approved to bid on this project, no alternates allowed. Only TCV shall furnish and install new control hardware and software. TCV WILL WORK DIRECTLY FOR CVUHS ON THIS PROJECT.

Web CTRL FMCS software is to be modified as required to provide new control functions to achieve final sequence of operations.

Furnish and install all control hardware and software for FMCS operation, trending, and alarming of the new ERU to achieve compliance with the new sequence of operation.

Upgrade existing graphics screen to include all controlled and monitored parameters for the new unit SYSTEM.



ERU SEQUENCE OF OPERATION: [subject to expansion based on reviews with TCV]

SCHEDULED OPERATION:

ERU SHALL OPERATE IN PARALLEL WITH THE AHU FOR THE ADMINISTRATION. LINK TO EXISTING SCHEDULING, NO CHANGES

OCCUPIED MODE:

ERU OA & EA MOD’S SHALL OPEN

ERU FANS SHALL BE ENABLED ON TO SPEED SET THRU TAB TO ACHIEVE 500 CFM.

MONITOR ERU OA, EA, RA & SA TEMPERATURES FOR TRENDING AND ERU EFFECTIVENESS CALCULATION.

DISPLAY ERU CALCULATED EFFECTIVENESS ON GRAPHICS SCREEN BASED ON CALCULATED RESULT FROM TEMPERATURE PROFILES. THIS EFFECTIVENESS IS ONLY VALID WITH UNIT RUNNING (ADD THIS NOTE TO SCREEN).

MONITOR/TREND/ALARM FAN CMD & STATUS; MOD CMD

MONITOR TREND AFS ON OA/EA AS ADD ALTERNATE

UNOCCUPIED MODE:

SAME AS AHU, MOD’S CLOSE & FANS ARE DISABLED. IN UNOCCUPIED MODE, SHOULD AHU BE CALLED ON FOR HEATING, ERU SHALL REMAIN DISABLED.

DAT CONTROL:

o THERE IS NONE, IT IS ONLY MONITORED. ALARM AND SHUT DOWN UNIT IF DAT FORM ERU DROPS BELOW 38F.

FREE COOLING:

THERE IS NO BYPASS ON THIS INSTALLATION. IT IS POSSIBLE TO DISABLE EA FAN SHOULD FREE COOLING BECOME AVAILABLE. HOWEVER, WITH A 500 TO 2500 RATIO, THE EFFECTIVENESS OF SUCH ID DEEM TOO LOW TO VALIDATE THE COST TO PROGRAM IN A FREE COOLING CYCLE AT THIS TIME. PROVIDE OWNER A COST TO DO SUCH SO IT CAN BE EVALUATED.

SAFETIES & ALARMS:

ALARM ON LOSS OF FAN STATUS AS ‘ON’ WITH ENABLE CMD

ALARM IF DAT DROPS BELOW 38F WEN ERU IS ENABLED.

TIE ERU FAN MOTOR ENABLE/POWER TO AHU SMOKE SHUT DOWN SIGNAL TO SHUT DOWN ERU SHOULD AHU BE SHUT DOWN ON DUCT SMOKE ALARM

TRENDING POINTS SET UP FOR COLLECTION AND TRENDS FOR 1 YEAR ON:

ALL 4 ERU TEMPERATURE PROFILES

ERU EFFECTIVENESS



SA & EA FAN CMD & STATUS

MOD CMD

AFS CFM AS ADD ALTERNATE

ADDITIONAL POINTS/SEQUENCES MAY BE ADDED AS REVIEWED THRU SHOP DRAWING PROCESS.

6 – STARTUP & COMMISSIONING: GWR Engineering proposes to oversee the implementation of this work and commission the system to verify their operation to the intent of this scope of work. Prepare the unit for startup and perform and document the startup following the installation manual and noted as follows:

PREFUNCTIONAL checks ‐ Installation verification: When the unit installation is completed and the contractor is ready to perform startup, contact the owner & engineer for verification of installation. DO NOT PERFORM STARTUP without this verification.

Once installation review has been made, any non‐conformances or deficiencies identified shall be corrected. Notify the engineer and owner of their corrections for final verification of installation and authorization to perform startup.

Once authorization for startup has been given, startup systems and controls (may be separate times) in coordination with engineer & owner on site following the installation/startup manual procedures.

The contractor shall complete (and provide the owner with a copy) a startup report that shall document the systems checks and functional operation verifications.

The contractor shall review with the owner all specific startup procedures and operations that involve the installed systems that may be of importance in operation or maintenance.

The owner shall sign off on an acceptance of installation form provide by the contractor indicating the date this review was performed and who the attending parties were on site for this procedure.

7 – CLOSEOUT & OWNER TURNOVER REQUIREMENTS:

Contractor to provide the following:

Documentation on the startup and owner acceptance of an operational demonstration.

Provide a complete set of Operations & Maintenance Manuals for all installed systems.

Contractor shall review the maintenance procedures on all equipment, devices and systems installed.

The contractor shall warrantee the work for a period of 1 year from the date of the acceptance document noted above. The contractor shall provide the owner with this warrantee document.

CONTROL SYSTEM shall have a complete review and verification of the required sequences of operation by GWR Engineering. Any deficiencies or Issues identified shall be corrected to the satisfaction of GWR Engineering before final payment on this project is made.



8 – BIDDING:

The school will be providing a bid document that WILL IDENTIFY THE REQUIREMENTS FOR INSURANCE AND SITE WORKING CONDITIONS.

BIDS WILL BE DUE ON APRIL 16, 2021 @ 2:30 PM (SEE SCHOOL DISTRICT BIDDING REQUIREMENT DOCUMENTS ASSOCIATED WITH THIS SCOPE OF WORK). ALL BIDS TO BE EMAILED TO Bill Root, CHRIS GIARD & TOM MONGEON.

THE BOARD WILL AWARD CONTRACT ON APRIL 23, 2021 based on compliance to bidding documents and pricing.

Provide a base bid that includes all work as identified above. There are no add alternates on this project currently.

IF the contractor wishes to provide additional work outside this scope, all these items must be listed separately for independent evaluation by the engineer and school.

9 – QUESTIONS:

Bill Root, PE at GWR can be contacted if there are technical questions, need for clarifications or explanation of anything in this scope of work.

10 – SITE VISIT: REQUIRED

SITE VISIT IS SCHEDULED FOR APRIL 7, 2021 @ 2:30. Respectfully submitted,

Bill Gordon (Bill) W. Root, Jr., P.E., HBDP, LEED AP, President

ASHRAE High-Performance Building Design Certified Professional

GWR Engineering, PC 130 Quarter Mile Rd Charlotte VT 05445 [email protected] 802-425-2825



ADMINISTRATION OFFICES – CFM TAB DATA FOR COST BREAKOUT



SECOND FLOOR PLAN – ASSUME 100 CFM EACH OUTLET

[Need to review 1993 plans to get these cfm values to match original design]

Documents

GWR Engineering, P.C. Consulting Engineers