nuair Enerboss 412C User manual

July 5/2011
Enerboss 400C Series Vertical Fan Coil
Specifications, Installation, Operation and Maintenance Manual

July 5/2011
1INSTALLATION .................................................................................... 3
Locating the Fan Coil......................................................................................... 31.1
Framing............................................................................................................... 31.2
Electrical Power Connection............................................................................. 31.3
Control and Electrical Connections.................................................................. 41.4
Plumbing............................................................................................................. 41.5
Ducting ................................................................................................................ 41.6
2COMMISSIONING................................................................................ 5
Supply Air Balancing......................................................................................... 52.1
HRV Balancing................................................................................................... 52.2
Water Side Commissioning............................................................................... 82.3
3OPERATING THE FAN COIL AND HRV/ERV................................. 8
General Description ........................................................................................... 8
3.1
Thermostat.......................................................................................................... 93.2
Dehumidistat Control (Optional)...................................................................... 93.3
24V Push Button Timers (Optional)............................................................... 103.4
Recommended Seasonal Settings.................................................................... 113.5
4MAINTENANCE.................................................................................. 12
Maintaining Return Filters and HRV/ERV Core......................................... 124.1
5WARRANTY.......................................................................................... 13
6TECHNICAL INFORMATION........................................................... 14
6.1 Nomenclature..................................................................................................... 14
6.2 Coil Data ............................................................................................................ 15
6.3 4-pipe Heating coil data ..................................................................................... 16
6.4 Fan Curves.......................................................................................................... 17
6.5 Outside Air at Low Speed.................................................................................. 18
6.6 Exhaust Air......................................................................................................... 18
6.7 HRV Efficiency.................................................................................................. 19
6.8 Sound Level Summary....................................................................................... 19
6.9 Shop Drawings................................................................................................... 19
6.10 Electrical......................................................................................................... 25
6.11 Operational States........................................................................................... 28

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1INSTALLATION
Locating the Fan Coil1.1
Clean the floor of debris where the fan coil is to be placed. With the fan coil tipped at the
top, feed the risers down to the unit below through the sleeves provided. Solder the
mating risers and insulate the remaining copper on the supply and return water risers.
Shim the fan coil plumb and level if necessary.
Framing1.2
Using nominal 2” studs, frame around the fan coil rough-in flange on the left, right, top
and bottom as shown below.
Electrical Power Connection1.3
Supply the fan coil with 120VAC terminating at the junction box provided inside the
unit. The table below outlines the breaker sizes needed.

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ELECTRICAL SPECIFICATIONS
Electrical Volts Watts MCA
No Electric Back up 120/1 400 15
1.5 kW Back up 120/1 1900 20
CONTROLS
POWER CONDUCTOR WIRES
THERMOSTAT 24 VAC 4 18 GA
DEHUMIDISTAT 24 VAC 2 18 GA
TIMERS 24 VAC 2 18 GA
TIMERS 24 VAC 3 18 GA
SPRING WOUND MECHANICAL COUNT DOWN
20-80% MAKE ON RISE
DESCRIPTION
HEAT COOL WITH FAN SWITCH
MOMENTARY PUSH BUTTON WIN20
Control and Electrical Connections1.4
Control wiring is 24 VAC. All controls terminate at a terminal strip inside the fan coil.
Thermostat connections (R,G,Y,W,C), High Ventilation Switch (Hum , 24V) and Dryer
interlock (Dryer SW), Push Button timers (24 V, Timer Sw, indicator).
Plumbing1.5
The coils come c/w drain and air bleed plugs on the headers. When charging the coils,
open the air bleed plug (top, return header) and manually open the control valve.
Ducting1.6
Supply Air1.6.1
Supply air options are: 1) Front, non-ducted. 2) Rear ducted 6x8 or rear ducted 14x8. 3)
Top ducted, 8” dia.
Return Air1.6.2
Return air options are front, back, left or right and are not typically ducted. A key
operated volume control return air damper supplied with the fan coil is necessary for
proper HRV balancing.
HRV Return Air (Exhaust Air from Building)1.6.3
At the top, front, left of the fan coil a 5” diameter collar is provided. The HRV return air
collar can be specified when ordering to be top or side and can be changed in the field by
swapping the cover plate and collar plate.
HRV Exhaust Air (Exhaust Air to Outside)1.6.4
At the top, rear, right of the fan coil a 5” diameter collar is provided. The exhaust air
collar can be specified when ordering to be top or side and can be changed in the field by
swapping the cover plate and collar plate.

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HRV Outside Air (Fresh Air from Outside)1.6.5
At the top, right, front of the fan coil a 5” diameter collar is provided. The outside air
collar can be specified when ordering to be top or side and can be changed in the field by
swapping the cover plate and collar plate.
2 COMMISSIONING
Supply Air Balancing2.1
The supply air motor is an ECM operating in constant cfm mode. Adding static will not
significantly reduce the total air flow as you would expect with a psc motor. On ducted
systems the amount of air at each grille can be regulated with dampers.
HRV Balancing
2.2
The HRV exhaust air can be adjusted in low and high speed using the control board and
the procedure that follows. The amount of outside air is adjusted using dampers. The
damper in the return air grille can be closed (partially) to increase outside air flow or
opened to decrease outside air flow. If outside air needs to be further reduced, a sliding
damper located in the HRV outside air compartment should be used.
When balancing the HRV:
-Close all windows, doors and
fireplace dampers.
-Turn off any exhaust systems
such as bathroom fans, range
hoods, central vacuums or
dryers.
There are three modes of
operation in which the HRV
needs to be balanced.
1) High speed (High ventilation
switch).
2) Low speed (thermostat fan
ON, no heat or cool calls).
3) Low ventilation with a call for heat or cooling.
Balancing Sequence:
High Speed Balancing –set supply and exhaust to the specified flows
Low speed balancing –Fan On. Reduce the higher flow to match the lower
Low speed with heat/cool call on –using the throttling damper, match the outside air
flow to that of the exhaust air.
Exhaust air
measuring
port
Fresh Air
measuring
port

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B
Balancing mode 12.1.1
High Speed Balancing:
With all dampers fully open and the exhaust fan speeds at
the factory setting, run the fan coil in high ventilation
mode. Using a hot wire anemometer or pitot tube and
micromanometer measure the air velocity (hot wire) or
velocity pressure (micromanometer) in the HRV return
and HRV outside air. The table below shows cfm values
for various meter readings.
2.3.1.1 Outside Air High Speed Adjustment
If the outside air flow is too low, gradually close
the return air grille damper (A) until the desired
OA flow is measured. If the outside air flow is too
high gradually close the outside air balancing
damper (B) until the OA flow is obtained.
Outside Air Return Air
Flow Velocity Pressure Velocity Pressure
CFM fpm inwc fpm inwc
30 238 0.0035 221 0.0030
40 317 0.0063 294 0.0054
50 397 0.0098 368 0.0084
60 476 0.0142 441 0.0122
70 556 0.0193 515 0.0166
80 635 0.0252 588 0.0216
90 714 0.0319 662 0.0274
100 794 0.0394 735 0.0338
110 873 0.0476 809 0.0409
120 952 0.0567 882 0.0487
Balancing
Ports

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2.3.1.2 Exhaust Air High Speed Adjustment
From the window in the HRV access door (C), locate the two blue
pots on the circuit board. The top pot adjusts the exhaust fan HIGH
speed. Turn clockwise to increase and counterclockwise to decrease
CFM. Adjust the exhaust flow rate to within 10% of the OA rate (step
2.2.1)
Balancing Mode 22.3.2
2.3.2.1 Low Speed Balancing
Measure and record the flow rate of the Outside Air with the fan coil
in low speed ventilation (fan On, thermostat system switch off) using
the same method described above. Note: No adjustment can be made
to this flow without affecting the high speed flow and repeating the
high speed balance.
Measure the exhaust air from building low speed flow.
Use the lower pot to adjust the exhaust fan LOW speed.
Turn clockwise to increase and counterclockwise to decrease CFM
Adjust until the flow matches that of the outside air.
Balancing Mode 32.3.3
2.3.3.1 Low Ventilation on a Call for
Heat
On a call for heat or cool the main fan motor
increases speed. To prevent over ventilating
during the call, a throttling damper (D) partially
closes the outside air opening. Several damper
stop points (E) are available on the throttling
damper assembly. 1) Measure the outside air
when the fan coil is in a call for heat and set the
stop to a more open position if more OA is
need for balance or a more closed position is
less OA is needed. 2) Adjust the OA flow
within 10% of the EA flow in low speed. The
exhaust air flow rate in a call for heat or
cooling should not change from that of low
ventilation mode.
A
C
D
E

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Water Side Commissioning2.3
The coil(s) must be fully charged and free of air. To determine the water flow through
the coil and the output of the unit measure the entering and leaving water temperatures
and the entering and leaving air temperatures with the fan coil in a call for heat ( or
cooling as appropriate). The water flow rate and unit output can be calculated with the
equations given.
C409 gpm = 0.7*{temperature change air (F)}/{temperature change water (F)}
C412 gpm = 0.9*{temperature change air (F)}/{temperature change water (F)}
C418 gpm = 1.0*{temperature change air (F)}/{temperature change water (F)}
C430 gpm = 1.8*{temperature change air (F)}/{temperature change water (F)}
C409 Btu/hr = temperature change air (F) *350
C412 Btu/hr = temperature change air (F) *450
C418 Btu/hr = temperature change air (F) *500
C430 Btu/hr = temperature change air (F) *900
3OPERATING THE FAN COIL AND HRV/ERV
General Description
3.1
The Enerboss Integrated Fan Coil has two fans:
The main fan circulates air in the space and also brings in fresh air from outdoors. A
smaller fan serves to exhaust air from the space (HRV exhaust).
Understanding Your Heat/Energy Recovery Ventilator (HRV/ERV)
The heat (energy) exchange system in the Enerboss provides ventilation air at a
prescribed rate to maintain a healthy, comfortable indoor environment while reclaiming
energy from the exhausted stale air.
3.1.1 How It Works
The HRV exhausts air from rooms in the home that produce the most odors, humidity,
VOC’s and other pollutants. This air is exhausted to the outdoors through a heat/energy
recovery core. At the same time, fresh air from outdoors is drawn into the HRV core
where the energy from the outgoing stale air is transferred to the incoming fresh air. The
conditioned fresh air is then blended with the circulating air of the heating/cooling system
and distributed to the living areas of the home through the supply ductwork (or direct
supply grills).
The Enerboss integrated HRV/ERV is a 2-speed system:

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When the thermostat switch is in Fan ON mode the HRV/ERV runs continuously on low
speed, increasing to high speed on call from a timer or optional dehumidistat.
When the thermostat switch is in Fan AUTO mode the HRV/ERV is in standby and will
provide low volume ventilation only on a call for heat, or will provide high speed
ventilation on call from an optional dehumidistat or timer .
Thermostat3.2
The thermostat should have as a minimum two switches:
A “system switch” controls the mode of operation (heat, cool or off), and a “fan switch”
controls fan operation (On or Auto).
System Switch3.2.1
System OFF: System does not react to heating or cooling.
System COOL: System is in cooling mode, fan coil comes on when room temperature
rises above set point.
System HEAT: System is in heatign mode, fan coil comes on when room temperature
drops below set point.
Fan Switch3.2.2
FAN AUTO (intermittent operation): The Enerboss will operate with a call for heating or
cooling or high ventilation from one of the remote controls. Fan operation will cease and
the unit will turn off once the call is satisfied. Low ventilation only occurs on a call for
heat or cool.
FAN ON (continuous): The Enerboss will constantly circulate air on low speed and
ventilate continuously in low volume. On a call for Heating or Cooling unit will go into
high speed cooling/heating and resume low speed after the thermostat is satisfied. On
call from a remote control the unit will go into high speed ventilation and resume low
speed after the remote is satisfied. This is the recommended setting for occupied spaces.
Dehumidistat Control (Optional)3.3
Excessive ambient humidity can be controlled with an optional wall mounted
dehumidistat. The dehumidistat will initiate high speed ventilation when the humidity
sensor detects humidity in the air around it to be higher than the dehumidistat set point.
In hi-speed ventilation the small exhaust fan will run at high speed and the main fan will
operate at high speed. The Enerboss will cease high speed ventilation when the humidity
sensor detects lower humidity than set point.
Note: Dehumidistat settings do not need to be changed frequently; usually once
when the weather starts to get hot and humid (late spring, early summer), and again
when the weather starts to get cool and dry (late fall, early winter).

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Typical seasonal settings for the dehumidistat dial are as follows:
Summer: 80% or OFF
Winter: 40-60%
Dehumidistat Wiring:
Use 2-Conductor low voltage wire. Connect to 24 VAC and Humidity
Dehumidistat Settings and Responses3.2.3
When Thermostat Fan Switch is ON
If indoor humidity is below dehumidistat set point the HRV runs in low speed. The HRV
fan and the main fan will operate in low.
If the indoor humidity rises above the dehumidistat set point the HRV runs in high speed.
The HRV fan and the main blower will operate in high until switch is disengaged.
When Thermostat Fan Setting - AUTO
If the indoor humidity is below the dehumidistat set point the main fan and HRV will be
off.
If the indoor humidity is above the dehumidistat set point the HRV runs in high speed.
The HRV fan and the main blower will operate in high speed.
24V Push Button Timers (Optional)3.4
Twenty minute timers (Part # WIN-20) may be located in bathrooms, kitchen or laundry
room for timed source control of humidity and odor. Engaging the timer sends the
ventilation system to high speed for twenty minutes to evacuate odor, excess humidity or
other indoor pollutants. Longer timed cycles can be obtained with mechanical timers.
Wiring
20 minute timers connect to: 24 VAC; Timer Switch and LED Indicator.
Mechanical timers connect to: 24 VAC and Humidity.
Timer Settings and Responses3.2.4
Thermostat Fan Setting - ON
The HRV fan and the main fan will operate in low. When the timer is ON the fan coil
will be in high ventilation mode. The HRV fan and the main blower will operate in high
until the switch is disengaged.
Thermostat Fan Setting - AUTO