ITEM 3.7 Ventilation system upgrade E WWTFof
Ot�co
MINNESOTA
DEPARTMENT INFORMATION
Request for
City Council Action
ORIGINATING DEPARTMENT
REQUESTOR:
MEETING DATE:
Utilities
Utility Manager Neidermeier
May 29, 2018
PRESENTER(s)
REVIEWED BY:
ITEM #:
Consent
City Administrator/Finance Director Flaherty
3.7
STRATEGIC VISION
MEETS:
THE CITY OF OTSEGO:
upgrade within the East Wastewater Treatment Facility Preliminary building.
Is a strong organization that is committed to leading the community through innovative
communication.
X
Has proactively expanded infrastructure to responsibly provide core services.
No
Is committed to delivery of quality emergency service responsive to community needs and
expectations in a cost-effective manner.
The 2018 Utility budget includes $50,000 to replace the Mechanical Air Unit (MAU) at the East Wastewater
Is a social community with diverse housing, service options, and employment opportunities.
expectancies. The MAU has required frequent repairs and is unable to satisfy air flow and exchanges for
Is a distinctive, connected community known for its beauty and natural surroundings.
AGENDA ITEM DETAILS
RECOMMENDATION:
Staff is recommending approval of the quote from Sentra-Sota Sheet Metal, Inc. for the ventilation system
upgrade within the East Wastewater Treatment Facility Preliminary building.
ARE YOU SEEKING APPROVAL OF A CONTRACT?
IS A PUBLIC HEARING REQUIRED?
No
No
BACKGROU ND/J USTI FICATI ON:
The 2018 Utility budget includes $50,000 to replace the Mechanical Air Unit (MAU) at the East Wastewater
Treatment Facility. The unit provides ventilation in the pretreatment building and has met life
expectancies. The MAU has required frequent repairs and is unable to satisfy air flow and exchanges for
the influent room and its harsh environment.
An evaluation of the Pretreatment Room was completed by Karges-Faulconbridge Inc. (KFI) Engineer Tom
Wentz and was received in January this year (attached). The memo identifies the need for MAU
replacement and was discussed at the March Public Works Subcommittee. Three quotes were sought, with
two being submitted by the May 18 deadline. The Engineer and staff are comfortable with the low quote
by Sentra-Sota Sheet Metal Inc. of $37,300.00 and recommend commencement of replacement.
SUPPORTING DOCUMENTS ATTACHED:
• Technical Memorandum — Karges-Faulconbridge, Inc.
• Quote — Sentra Sota Sheet Metal, Inc.
• Quote — Master Mechanical
POSSIBLE MOTION
PLEASE WORD MOTION AS YOU WOULD LIKE ITTO APPEAR IN THE MINUTES:
Motion to approve the Sentra-Sota Sheet Metal, Inc. quote for Mechanical Air Unit #1 replacement at the
East Wastewater Treatment Facility for $37,300.00.
BUDGET INFORMATION
FUNDING:
BUDGETED:
602 —sanitary Sewer Fund
Yes
Karges-Faulconbridge,Inc. Menginev".corn
Frrginoers
MEMORANDUM
Date:
January 8, 2018
To:
Scott Schaefer
From:
Tom Wentz
Re:
Otsego East WWTF
KFI Project Number:
17-386
Subject: Screen Room Ventilation Evaluation
The purpose of this memo is to provide a summary of our recent, November 21, 2017, site
observation of the Pretreatment Building —Screen Room mechanical heating and ventilation systems
as well as recommendations for improvements to the space heating and ventilation. During the visit
we reviewed the current operation and condition of the existing mechanical systems.
The Screen Room addition was built in 2001/02 as a part of a facility improvements project. The
room is approximately 1000 square feet, and 8,300 cubic feet.
A direct gas fired make-up air unit was installed to provide 1,400 cfm (10 AC/H) while operating at a
"high speed" mode and 700 cfm (5 AC/H) while operating at a "low speed". The maximum heating
capacity of the make-up air unit is 154.0 MBH which was designed to provide a 100 degree
temperature rise at full air flow. The speed of the unit was originally intended to be interlocked with
the space lighting circuit such that it would operate at the "high speed" mode when the space is
occupied and the lights turned on. Otherwise the system would operate at "low speed".
A carbon based odor control system was provided to treat the Screen room exhaust air at the same
"high and Low" air flow rate as the make-up air unit.
No supplemental heating was provided to the space when it was constructed.
General observations:
The ventilation system was initially set up for 2 -speed operation. It has been determined by
the WWTF staff that the low speed operation does not remove enough 1-12S from the space
and the 2 -speed operation was abandoned and the system operated at only a high speed
mode. The VFD has been manually set at 50 Hz for both the make-up air unit and the Oder
control unit. Air flow rates were not measured or adjusted at these operating speeds.
Review of the project Test & Balance reports show that these two systems were apparently
not measured or balanced.
11 Page
Otsego East WWTF— Pretreatment Building Heating and Ventilation
t F'Ilginoors
Karges-FaullConbridge,Inc. Merrghwers.com
- Observation was that there is substantially more exhaust air than supply air as the room was
at a very negative air pressure when observed. The room only needs to be slightly negative
in order to control and capture the escape of gases (142S). The extreme negative room air
pressure is impacting the quantity of infiltration of untempered (unheated) air around the
doors and through the connecting influent and effluent pipe systems.
- Generally the space is not receiving enough heat when the ventilation systems are operating
at high speed and has been experiencing some freeze ups during the past several years. The
make-up air unit is approximately 16 years old and while is generally good physical
appearance the average life expectancy for this type of equipment is 15-20 years. The
performance of the heating portion of the equipment may no longer be functioning as
intended or required. Further some of the system sensors appear to be corroded and may
not be functioning properly.
- The supply air duct between the make-up air unit and the building is not insulated.
- There are no covers over the water channels and at times there is a substantial amount of
aeration that was observed while the waste water was flowing.
- There is no redundant or back-up heating with -in the Screen Room.
- The Calgon Odor scrubber is working well but it is also 16 years old and is also past its
average life expectancy.
Discussion Items:
Based on current code requirements, NFPA 820, the space electrical rating is C1/D1 if
ventilated at less than 12 AC/H continuously. The space electrical rating can be reduced to
C1/D2 if ventilated continuously at 12 AC/H or higher. Even though the space rating can be
reduced it is generally not recommended to reduce the rating. The current codes require a
combustible gas detector to be provided in the space as well.
- The generation of 112S gas in the room is likely increased due to the splashing and aeration of
the waste stream as it flows through the various exposed portions of the channel in the
room.
Recommendations:
Provide a supplemental or backup heat source to the Screen Room. This is helpful if/when
the ventilation system were to be off for servicing or maintenance. The supplemental
heating can also provide extra heat to specific areas in the room more at risk for freezing.
During the site visit, it was observed that an explosion -proof 15 kW electric heater was
located in the adjacent electrical room, which at one time had been the plant influent
channel. This space is now interior and need very little heat. It was recommended to
relocate this electric unit heater into the Screen Room to provide for supplemental heat.
2 1 P a g e
Otsego East W WTF — Pretreatment Building Heating and Ventilation
Karges-Faulconbridge,Inc. I Mengineers.corn
V
Foyi �ool—s
Construction cost estimate to $1,250.
2. Insulate and jacket the supply air duct between the make-up air unit and the building. The
tempered air being supplied by the make-up air unit is losing heat.
Construction cost estimate to $2,500.
3. Remove and replace existing make-up air unit as it is past its average life expectancy. The
new unit should be sized to provide 12 AC/H (approximately 1,700 cfm) with a heating
capacity of 165.0 MBH. System to be provided with new controls and sensors.
Construction cost estimate to $25,000.
4. Rebalance the supply and exhaust air systems air flow rates to provide a slight negative room
air pressure.
Construction cost estimate to $1,500.
5. Provide covers over the water channels where possible to reduce the amount of off-gasing
directly into the room.
Construction cost estimate dependent on what is done.
6. Remove and replace existing carbon odor scrubbing unit as it is past its average life
expectancy. The new unit should be sized to match the supply air from the make-up air unit
at approximately 12 AC/H (1,700 cfm). System to be provided with new controls a new
Sound attenuated fan enclosure in lieu of the current site constructed enclosure. (See
attached information).
Construction cost estimate to $90,000.
31 Page
Otsego East WWTF — Pretreatment Building Heating and Ventilation
L
B
P
ECS V1 CARBON ADSORBER SYSTEM
MODEL: 60 SERIES V1-84-2000
CARBON CAPACITY:
115 Fe (3' BED DEPTH
BED VELOCITY:
52 FPM
EBRT:
3.46 SECONDS
SYSTEM PRESSURE DROP:
4.8" W.C.
FAN DATA
MODEL:
NYB RFE315
DESIGN:
2000 CFM ® 10" W.C.
MOTOR:
I 3-60-230/460V; 10 HP; FLA 14 AMPS
/
NOTES:
1, ALL FLANGES PER PS 15-69 UN LESS OTHERWISE NOTED
2. VESSEL CONSTRUCTION IS FRP
-RESItl SYSTEM IS A CLASS I FLAME RESISTANT VINYL ESTER
-ALL INTERNAL SURFACES HAVE A 100 -MIL COROSION BARRIER
-EXTERIOR SURFACESTO HAVE UV -INHIBITOR APPLIED
3.NOZZLE ORIENTATIONS ARE PLACED FOR CLARIFY AND CAN BE CHANGED TO FIT SITE
CONDITIONS
4. NEMA 4X MOTOR STARTER MOUNTED 3: FROM AIR STREAM.
5. DRAIN PORT MAY HAVE CONSTANT DRIP AND SHOULD BE PLUMBED AWAY FROM
THE SYSTEM WITH SIX-INCH WATER TRAP. IF FREEZING CONDITIONS MAY EXIST. THIS
EXTERNAL PIPING SHOULD BE INSULATED AND HEATTRACED (EXTREME CONDIIIONS)
6. IF THE ODOR CONTROL SYSTEM IS INSTALLED OUSIDE INA COLD CLIMATE. AND THE
INFLUENT AIR IS WARM / MOIST, A Z'THICK FACTORY APPLIED INSULATION SYSTEM IS
RECOMMENED
7. COLORS OPTIONS ARE GRAY, WHITE, OR TAN.
8. CONSULT ECS FOR MEDIA SELECTION. DIFFERENT CARBONS OR POLISHING AGENTS
ARE OFFERED BASED ON TREATMENT OBJECTNES AND CONCENTRATIONS WITH THE
INTENT TO OPTIMIZE MEDIA LIFE
ESTIMATED ASSEMBLED WEIGHTS:
EMPTY: 1659#
FLOODED: 15997#
OPERATING: 5354#
J
F
4.19in
SKID
HEIGHT
T
LOUVER
PRE -FILTER CAN BE
RELOCATED, BUT AIR FL(
MUST BE UPWARD OR
HORIZONTAL THROUGH
OPTIONAL ACCESSORIES:
-ECS SOUND ABSORB ENCLOSURE
ECS GUARDIAN PRE -FILTER
- EPDXY COATED STEEL SKID
File: 60S V 1-84-2000 V 1 System Pad Asy
TOLRA ¢Wumonaen: mc>ffs °enwry ometow a/a/zois
' TITLE:
°ECux :Ola TNG APiR.
AviR V1 -84 2000 CFM
uiG
A.
IGlsuicMc iFx: is
i�crc C.— `� ` C SIZE DWG. NO. REV
V1-84 A
SCALE: 1:36 SHEEf2OF5
E
A�
i
i
i
A�
MOTOR SIDE
B B
6:
AIR INLET SIDE
SECTION A -A
SECTION B -B
GENERAL NOTES:
• CONSTRUCTION
• WALLS VACUUM -FORMED WITH TWO LAYERS OF FRP OVER A
HONEY -COMB CORE
• RESIN, LINER, AND COLOR TO MATCH VI CONSTRUCTION
• SPLIT LINE TO BE CENTERED ON FAN HOUSING
• 2'OF ECS SOUND -ABSORB LINING ON ALL INTERNAL SURFACES
• STANDER FEATURES:
• TWO HINGED ACCESS DOORS WITH TOGGLE CLAMPS
• TWO ACOUSTICAL LOUVERS
• OPTIONAL FEATURES
• CUSS I DIV I EXHAUST FAN
• TEMPERATURE SWITCH
INTERNAL LIGHTE (AVAILABLE ON URGER ENCLOSURES)
In
ACCESS DOOR
DETAIL
File: 60S V 1-84-2000 Sound Enclosure
FILE:
Sound Enclosure
SIZE
B
DWG. NO. REV
SE -01 A
SCALE: 1:241 TSHEET30F5
D .f—
D�
168.00ln
4.191n
108.00in
�
4.191n JTSECTION D -D
I C
r0 15.411n I
SECTION C -C
SCALE I:12
k 012.00in
L
9
C
B
P
Part r Part Number
Housing ECS -GUARD -2
Combination Pad ECS-GFME-200Q
Differential Pressure Gauge ECS -DP -2015
REVISIONS
DESCRIPTION DATE APPROVED
mind Release 8/18/2015 1JG
2. Standard end connections are sized per ASTM 3982 / NBS PS 15-169 Table 2 parameters.
If alternate connection saes are necessary please specify when ordering.
3. ECS Guardian prefliers come standard with a mechanical differential pressure Indicator.
4. Pressure drop with clean pad at the design airflow will be .5" w.c.
5. Pressure drop with duty pad of the design airflow will be 1.25' w.c.
6. Performance: 99% removal of particles 10 micron or larger
7. For applications where moisture removal Is not desired an alternativeParticulate / grease
removal pad can be supplied. Contact ECS technical service for additional information.
8. Base drain connection should be piped away from the unit
9. Effluent piPIng should include a water trap to prevent hold-up of liquid due to negative
pressure In the prefilter housing. If freezing conditions exist this piping should be heat
traced and Insulated.
10. FRP housing Is manufactured using a vinyl ester resin system with a class 1 flame spread
rating. Al interior surfaces have a 100-m1 corrosion liner, exterior surfaces are gelcoated
and contain a UV Inhbitor. Standard colors are grey, white or tan.
Please specify when ordering
11. Client to advise Inlet CL helgght Men ordering
12.30" of clearance required at access door for pad removal
UrRESS OIlSR1iEESPK61H1: "A GAtE
m+ws+G+G eREn+r.+ass CAD F
oRAm DTagtow 8/18/2015File: ECSGFME2000.27X27 Asy
eRAOG¢ TRE:.r11+GULAR: 6L C Q@S1i OIOE APiR.
oA,.L Prefilter - 2000 cfm
MRFEPIACEGECUAL f +/JG MPR
rcrmwrW +oIEq.PiNCB�GfR+�
nffesoPruw+ inw� SIZE DWG. NO. REV
meEn'ca .wse+ry uux+ars>. ury rzR See Notes i�13S B
o�cnGnn+P>s uAvnw+E m
+ L r> a See Notes cuv+nor+nulTAL soLunot+s
+e.rt+as c oaevm+c SCALE 1:12LVE 46.65 SHEETS OFS
UNIT SPECIFICATIONS
Rep Job # Quote # Revision Date
6444 0 12/01/17
Job Name Tag #
Model: TA -109 NG HRH Otsego Waste Water Treatment Plant- Wentz Assoc MAU
Optional Eauipment Included:
Structural Unit Stand'
- Stand Type: Open Structural Steel
- Outside Air Intake Hood*
- Type: Hood/ Filter Combo
- Filters: 1" Cleanable
- Finish: G-90
- Discharge Damper & Actuator"
Type: Low Leak
Finish: G-90
Optional Controls Included:
- ETL Label (ANSI Z83.4 / CSA 3.7)
- Door Interlocked Non -Fused Disconnect
- Low Fire Start
- High Gas Pressure Switch
Low Temp Safety
- Inlet Ductstat
- Clogged Filter Switch I Switch w/ Light
- Occupied/Unoccupied Switch
- Operating Lights
Control Relay
- Contact I Relay contacts start exhaust fan (by others)
- Energized I Relay energized when airflow is proven
- Factory Mounted VFD wt Vent Package
- VFD Fuses / Circuit Breakers (By Others)
NOTE: Options Ending With `Are Shipped Loose For Job Site Installation
Base Unit Estimated Weiaht in Lbs.
TA -109 Unit Base 600
Liner I G-90 I Entire Airstream 105
Total: 705
Optional Equipment Estimated W61-ght in Lbs,.
Hood I Filter Combo 111" Cleanable I G-90 70
Discharge Damper I Low Leak I G-90 50
Total: 120
Grand Total Weight: 825
John J. Morgan Co. - Neill Gustafson For Submittal Use Only - NOT For Construction Page 2 of 7 12/1/2017 8:23:33 AM
UNIT DRAWING
Rep Job # Quote # Revision i
I Date
6444 0 12/01/17
Job Name Tag #
Model: TA -109 NG HRH Otsego Waste Water Treatment Plant- Wentz Assoc MAU
C
0
J
Overall Dimensions
A B C
62 38 30
Discharge Dimensions
D E F G
4 4 16 16
Intake Dimensions
H J K M
25 20 2 2
John J. Morgan Co. - Neill Gustafson For Submittal Use Only - NOT For Construction Page 3 of 7 12/1/2017 8:23:33 AM
Model: TA -109 NG HRH
Hood / Filter Combo Hood
ACCESSORY DRAWINGS
Rep Job # Quote # Revision Date
6444 0, 12/01/17
Job Name Tag #
Otsego Waste Water Treatment Plant - Wentz Assoc MAU
A B C D E F G H 1
25 20 51
Low Leak Discharge Damper
C 1
All,
A B C Q E F G H 1
16 16 12
John J. Morgan Co. - Neill Gustafson For Submittal Use Only - NOT For Construction Page 4 of 7 1211/2017 8:23:33 AM
�
��Riillliliil Rep Job # Quote # Revision Date
6444 0 12/01/17
Job Name Tag #
Model: TA -109 NG HRH Otsego Waste Water Treatment Plant - Wentz Assoc MAU
I -
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s
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�i Sit _... _.. -. y -,r -' "' r Y.. -,•,r7„ _ a.{ir
i
q ,,,-
Q 5.iq 10!7!? 1500 2000 2S4r.-
Flow(cfm) —;; ;tem — —— BHP ihpi
Component
Static Pressure
Unit
0.605
0.500
0.024
0.052
0.033
0.000
0.000
0.000
0.000
0,000
0.000
ESP
Hood / Louver
Filters
Dampers
Diffuser
Heating Coil
Cooling Coil
Evaporative Cooler
Energy Recovery Cell? Wheel
Custom Items
TSP: '
1,214
John J. Morgan Co. - Neill Gustafson For Submittal Use Only - NOT For Construction Page 5 of 7 12/1/2017 8:23:33 AM
Model: TA -109 NG HRH
Abbr.
Description
AH-#
Audible Alarm
CLK-#
Time Clock
DM-#
i Damper Actuator
FQ-#
Variable Frequency Drive
FS-#
i
Flame Safety Control
FU-#
Fuse
GA-#
' Graphic Display Adapter
GDS#
�i Graphic Display
GP-#
Gas Pressure Regulator
GT-#
Manual Shut-off Valve
LT-#
Indication Light
LTS-#
Low Temperature Safety
MC-#
Motor Speed Controller
MT-#
Blower Motor
OL-#
Motor Overload
P-#
Pressure Switch
PB-#
Power Distribution Block
Programmable Controller
PC-#
GAS TRAIN DIAGRAM:
Titan gas train starts here
I
rGT-
L,J
Shut-off valve, dripleg,
and union by others
'GEN. PARTS
LIST/GAS
TRAIN
Date
Rep Job #
Quote It Revision i
6444 0
12101/,17
Job Name:
Tag'#
Otsego Waste Water Treatment Plant - Wentz Assoc
MAU
Abbr.
Description
PS-#
Pressure Transmitter
PT-#
Potentiometer
R-#
Control Relay
SD-#
Smoke Detector
SR-#
Service Receptacle
ST-#
Motor Starter
SW-#
j'
Switch
T-#
I Temperature Stat
TC-#
Temperature Control
TD #
Temperature Select Dial
TDR-#
Timer Relay
TL-#
Temperature Limit
TR-#
Transformer
TS-#
Temperature Sensor
V-#
Safety Shut-off Valve
VF-#
Vestibule Vent Fan
VM-#
Modulating Valve
Denotes Control Cabinet Terminal Block and Wire Number
0 Denotes Remote Panel Terminal Block and Wire Number
---_ Denotes Field Wiring By Others
*P-3
*-
*V-3
*GP -1 ^V- VA , �GGT-3�V�-
PG -1 GP -2 V-1
John J. Morgan Co. - Neill Gustafson For Submittal Use Only - NOT For Construction Page 6 of 7 12/1/2017 8:23:33 AM
5/17/18
Kurt Neidermeier,
Otsego East Wastewater Treatment Facility
5850 Randolf Ave
Otsego Mn 55374
Project: Pretreatment Room Ventilation System Upgrade
3075 3�d Street South ■ PO Box 400
Waite Park, MN 56387
Office: 320-252-3992 ■ Fax: 320-252-5479
www.sentra-sota.com
We propose to furnish & install a new Make-up air unit as per plan drawings M1, M2, & M3,
Includes -
New Titan MUA per the equipment schedule.
Demolition.
Electrical wiring.
Control wiring.
Gas piping.
Two new supply air registers at new location.
Duct.
Insulation.
Start-up.
Test & Balance.
Base Bid = $37,300
Have seen 0 addendums.
Thank ou,
P &"z�jv
Jeff Bechtold
Commercial Heating, Ventilation, Air -Conditioning & Architectural Sheet Metal
Design -Build I HVAC I Plumbing I Piping I Service
May 18, 2018
PROJECT: Otsego East WWTF - Pretreatment Room Ventilation System Upgrade
We offer this MECHANICAL PROPOSAL based on plans and specs dated April 10, 2018 by KFI.
We acknowledge no Addendums.
Total Base Bid:
$ 55,700.00
The following bid division sections are included in the above proposal price:
• Mechanical, Electrical, Controls, T & B complete as shown on the drawings and Bid Scope
• No Fire Protection
• Startup and Owner Training will take place the same day
• Proposed Suppliers: Titan on MUA Units, ABB on VFD's, T&B on SS Grilles
• Proposed Subs: Approved Equal on Controls, EIM on Electrical, TABA on Balancing, NYCO
on Insulation
• Lead Time on MUA Units are 9-10 weeks after approval
The following items are not included in the above scope of work:
• General Condition Items
• Temporary Facilities such as heat, cool, power, etc.
• Overtime
• Bond
• Builders Risk
• Payment terms Net 30
• Mechanical Work
• Sprinkler Piping
Thank you for the opportunity to bid this work.
Sincerely,
MASTER MECHANICAL, INC.
Rob Lund
Phone: (651) 789-4944
1027 GEMINI ROAD I EAGAN, MINNESOTA 55121 I Office: 651.905.1600 I Fax: 651.905.1601
www.mastermechanical.com