HomeMy WebLinkAboutMechanical Plan Aquatic Bath Sept8GENERAL NOTES
1.All duct gauges and supports per 2021 International Mechanical Code and SMACNA Duct
Construction Manual.
2.Insulate supply and return duct work where not located in conditioned space with minimum R-6
Johns Manville Permacote Linacoustic R-300 liner or wrap. Insulate all outside air ducts with
minimum R-8 Johns Manville Permacote Linacoustic R-300 liner.
COMPLETION
Provide Test and Balance Report, Equipment Startup Test Reports, Operation and Maintenance Manuals,
and As-built Record Drawings, as applicable, to Owner upon Project Completion.
SCOPE OF WORK:
·Remove existing gas fired make-up air unit. Disconnect gas piping, ductwork, line voltage, and control wiring.
·Provide and install (1) Greenheck brand vertical discharge type gas fired make-up air unit. New unit to be rated at
4.7 mbtuh's and deliver approximate 58,000cfm of air at a 1.3 esp. with 40hp supply air fan motor controlled by
VFD drive.
·Provide boom truck and operator for removing existing unit and setting new unit. Provide metal recycling services
for removed make-up air unit.
·Reconnect 2psi gas piping system. Check for leaks and verify correct burner manifold gas pressure.
·Reconnect 460V-3phase electrical circuit.
·Tie new unit into existing concentrator unit.
·Fabricate and install new discharge supply air ducting to transition to existing ducting system. Seal exposed
ductwork with appropriate rated mastic.
·Provide air balancing services to verify total overall airflow is being delivered per design.
·CTS. Check, test, and start new make-up air unit to ensure it is operating properly.
·Provide one-year warranty on materials installed and workmanship.
·ASEI personnel to go through required Aquatic Bath safety training.
SEQUENCE OF OPERATIONS
Unit Controls
The unit shall be provided from the factory with:
·24VAC Transformer
·Terminal Strip
·Supply Fan VFD
·Factory mounted and wired outdoor air inlet damper with actuator
Microprocessor Controller
The microprocessor control shall be factory programmed, mounted,
wired and tested. Controller shall have a lighted LCD display and keypad
for changing set points and monitoring unit operation. The controller shall
be equipped with the following sensors:
·Outdoor air temperature sensor
·Supply discharge temperature sensor
Unit Start Command
A contact closure or jumper wire must be field wired between terminals R
and G to enable the unit. When terminal G is energized the unit shall operate
as described below. When terminal G is de-energized the unit is disabled.
Internal Time Clock (Schedule)
The microprocessor controller is equipped with an internal 7-day
programmable time clock, allowing the user to add up to seven different
occupancy schedules.
Occupied/Unoccupied Modes
The microprocessor controller offers the following modes for determining
occupancy:
·The internal time clock
·A remote contact (see wiring diagram for details)
The unit can be temporarily overridden to the occupied mode via a dry
contact or the keypad display. After the override time has expired (1 hr,
adj) the unit will return to the scheduled occupied/unoccupied mode.
Occupied Mode Unit Start-Up Sequence
·Unit enable input must be closed (contact closure between R and G).
·Initial delay, microprocessor controller initialization sequence.
·Factory mounted and wired outdoor air inlet damper actuator is powered open.
·Supply fan starts after adj. delay.
·Tempering operation begins (see modes below).
Supply Fan Sequence (Occupied)
The unit has been provided with a factory mounted variable frequency drive
(VFD). The variable frequency drive shall control the supply fan speed as
indicated by the following sequence:
Constant Volume:
The VFD shall be programmed from the factory for a constant supply fan
speed. This is to be adjusted for air balancing only and is not to be
modulated.
Heating Control
The heating will be locked out when the outside air is above the heating
lockout set point (65 F adj.). When enabled heating will be controlled as
follows:
Direct Gas Fired Heating
The microprocessor controller will modulate the direct gas burner to
maintain the active supply temperature set point.
Supply Temperature Set Point Control (Occupied)
The active supply temperature set point shall be adjusted (field selectable):
·Locally at the controller. Unoccupied Mode (Disabled)
·Supply Fan Is OFF
·Factory mounted and wired outdoor air inlet damper actuator is de-energized
and spring returns to the closed position.
Supply Air Low Limit
If the supply air temperature drops below 35 F (adj.) for 300 seconds (adj.),
the controller will de-energize the unit and generate an alarm.
Alarm Management
The microprocessor controller will monitor the unit status for alarm
conditions. Upon detecting an alarm, the controller will record the alarm
description, time, date, available temperatures, and unit status for user
review. A digital output is reserved for remote alarm indication.
Possible Alarms Include:
·Global Alarm Indication that one or more alarms are present.
·Outdoor Air Inlet Temperature Sensor Alarm Outdoor Air Inlet
Temperature Sensor Alarm: Failure of the outdoor air inlet temperature
sensor.
·Supply Air Discharge Temperature Sensor Alarm Failure of the supply
air discharge temperature sensor. Unit is shut down.
·Supply Air Low Limit Alarm Supply air has fallen below 35 F (adj.) for 300
seconds (adj.). Unit is shut down.
·Dirty Filter Alarm
Indicates the pressure across the filters has increased above the dirty
filter pressure switch setting (field adjustable)
·Direct Gas Burner Alarm Indicates an ignition controller flame failure
alarm. Requires manual reset at the unit.
·Supply Fan Alarm Indicates the supply fan failed to prove for a 30 second
(adj.) period.
SUPPLY
DUCT
Horizontal Discharge Gas-Fired Make-Up Air Unit Schedule
I.D. No.Mfr. & Model Type Area Served Input (MBH)Output (MBH)Efficiency CFM Minimum OSA
CFM
Motor
RPM Total S.P.Fan H.P.Voltage Ph.MCA
(Amps)
MOP
(Amps)Gas Connection Control Filter Frame Sones Op. Wt.Notes
MUAU-2 Greenheck VSU-230-H50 - Vertical Orientation Direct Gas Heat / No Cooling Production 5174.6 4760.6 92%58,000 100%1725 1.311 40.0 460 3 65.9 110 2-1/2"VFD 20"x25"x2" (42)80 5,691 lbs
SUPPLY
DUCT
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