Enerzone CAH 33-44-50 Maintenance and service guide

CAH SERIES
INSTALLATION & MAINTENANCE
MODELS
CAH 33-44-50
CAH 49-54-70

2
CAH VARIABLE SPEED AIR HANDLERS
DIMENSIONS............................................................................3
TECHNICAL SPECS.................................................................4
INSTALLATION DON’TS.................................................................... 5
INSTALLATION DO’S ......................................................................... 6
FREEZE STAT REQUIRED FOR AIR CONDITIONING................... 7
INSTALLATION INSTRUCTION ...........................................8
LOCATING THE AIR HANDLER ....................................................... 8
LINE AND CONTROL WIRING REQUIREMENTS.......................... 8
SUPPLY AND RETURN DUCT REQUIREMENTS........................... 9
THERMOSTAT SELECTION............................................................. 12
SELECTING FAN SPEEDS ................................................................ 12
BLOWER MOTOR WIRE SELECTION CHART.............................. 13
HOT WATER COIL PIPING............................................................... 14
OPERATION AND MAINTENANCE ...................................15
INITIAL START-UP............................................................................ 15
AIR FILTER......................................................................................... 18
BLOWER MOTOR.............................................................................. 18
CIRCULATION PUMP REPLACEMENT ......................................... 18
PUMP CONTROL: ..................................................................19
SEQUENCE OF OPERATION IN HEATING MODE:...................... 19
TROUBLESHOOTING...........................................................20
MOST LIKELY PROBLEMS AND CAUSES.................................... 20
FAULTY CIRCUIT BOARD:.................................................22
WIRING DIAGRAMS.............................................................23
REPLACEMENT PARTS LIST..............................................24

3
DIMENSIONS
MODEL
A
B
C
D
E
F
CAH 33-44-50
17”
23”
35.5”
12”
18”
11”
CAH 49-54-70
21.25”
23”
43.75”
16”
18”
17”
ALL MEASUREMENTS IN INCHES

4
TECHNICAL SPECS
MODEL
CAH 33-44-50
CAH 49-54-70
@ 600 CFM
37,000 *
-
@ 800 CFM
45,000 *
-
@ 1000 CFM
52,000 *
58,000 **
@1200 CFM
-
65,000 **
@1600 CFM
-
76,000 **
POWER
SUPPLY
120 VAC, 1PH,
60HZ
120 VAC, 1PH,
60HZ
TOTAL AMPS
5.5
9.5
MAXIMUM FUSE
15
15
TRANSFORMER
30 VA
30 VA
BLOWER
MOTOR
1/3HP ECM
3/4HP ECM
PUMP
3 SPEED
3 SPEED
WATER
CONNECTIONS
1/2"
1/2"
FILTER SIZE
12" x 20" x 1"
18" x 20" x 1"
*OUTPUT (BTU) @ 3GPM
** OUTPUT (BTU) @ 4GPM

5
INSTALLATION DO’S AND DON’TS
INSTALLATION DON’TS
Do Not use with piping that has been treated with chromates, boiler seal or other
chemicals.
Do Not add boiler treatment or any chemicals to equipment and related piping, since the
piping contains potable water for Domestic Use.
Do Not use with ferrous piping. The system should be installed with new piping that is
suitable for potable water, such as copper. DO Not use with PVC Piping.
Do Not use valves that may cause excessive restriction to water flow. Use Full Flow Ball
or Gate Valves Only.
Do Not use unit with any water heater not having a properly sized and installed
Temperature and Pressure (T&P) Relief Valve. Some water heaters include factory-
installed valves. Others must be field-installed. Follow the instructions of the water
heater manufacturer and local codes when installing the T&P valve.
Do Not alter the water heater controls, dip tube, relief valve fitting, etc.
Do Not install unit or connecting piping in any manner except as shown in this
instruction manual.
Do Not install a DX cooling Coil in close proximity to the Hot Water Coil. A DX
cooling coil should be a minimum 12 inches away from the Hot Water Coil and a freeze
stat must be installed on the DX coil to prevent freezing of the DX Coil which in turn
may freeze the Hot Water Coil and cause damage or water escape.
Use EXTREME CAUTION when fastening duct work to coil area. Screws should be
no longer that 3/8” and should be fastened into the flange rather than the face of the
unit. This will reduce the risk of puncturing the copper tubing on the coil.

6
INSTALLATION DO’S
Do flush out all supply and return water lines between the unit and the water heater after
installation and before start-up to eliminate flux, metal chips, sand, or any other
particulate matter just as you would with any other plumbing systems.
Do use only non-lead solder and flux agents.
Do remember to install a properly designed mixing valve to the domestic service should
the water heater be set as to deliver water at a temperature greater than 120 °F.
*SPECIAL NOTE*
SOME JURISDICTIONS may require a backflow preventer in the incoming cold water
line to the water heater. In such cases the Temperature and Pressure Valve of the water
heater may weep OR relieve due to expansion of the water when heated. Note that this
would occur even if this air handler were not installed. A small diaphragm-type thermal
expansion tank will normally eliminate the weeping condition. Please read and follow
the manufacturer’s instruction for installation of such tanks.
Further Note : The above DO’S and DON’TS apply to air heaters which are
installed with water heaters in a hydro-air application.
However, our air handlers can be installed on closed loop boiler systems as well. When
doing so, make sure you follow all locally approved codes and installation practices.
In keeping with our policy on continuous product improvement, we reserve the right to
make changes without prior notice.

7
FREEZE STAT REQUIRED FOR AIR CONDITIONING
A freeze stat MUST be installed for systems that have air conditioning to
minimize the chance of the hot water coil freezing during a call for
cooling. The freeze stat typically opens at 38˚F, closes at 60˚F, and is
wired to interrupt the A/C compressor operation.
Mount the freeze stat on the suction line of the cooling coil and wrap with
cork tape covering both the stat and the suction line.
If the freeze stat is not securely fastened and insulated to the suction line
the compressor may not shut off if the evaporator coil freezes up.

8
INSTALLATION INSTRUCTION
ENERZONE assumes no responsibility for the installation of equipment that is in
violation of any building code, plumbing code, or electrical code requirements. These
instructions give information specific to installation of CAH fan coil units only. For
other related equipment, refer to proper instructions supplied by others.
LOCATING THE AIR HANDLER
THE INSTALLER MUST COMPLY WITH ALL LOCAL AND
NATIONAL CODE REQUIREMENTS RELATING TO THE
INSTALLATION OF THIS EQUIPMENT. BUILDING CODES ARE
CONSTANTLY CHANGING.
THE INSTALLER IS RESPONSIBLE TO MEET THEM.
CAH units can be installed in multi-positional applications and all models comply with
zero clearance installation to combustible materials. Sufficient clearance must be
provided to allow access to electrical controls and to the blower motor assembly for
servicing. This clearance distance should be approximately the same as the depth of the
fan coil unit at a minimum.
LINE AND CONTROL WIRING REQUIREMENTS
All wiring must meet with local and national code requirements. Units are
provided with wiring diagrams and serial-plate data to provide information
required for necessary field wiring. Knockouts are provided on the
cabinet for connection of power supply. These fan coil units are provided
with a transformer for 24-volt control circuits. Electrical connections
should be made according to the electrical diagram located on the reverse
side of the electrical panel cover.

9
SUPPLY AND RETURN DUCT REQUIREMENTS
All duct work must adhere strictly to all local and national code
requirements. It is critical that the return air duct has the same free area as
the opening provided on the fan coil unit. If there is no ducted return,
installation codes may limit the unit to installation only in a single story
residence. Ducting should normally be sized for external static pressures
of 0.15 to 0.3 inches H2O total.
Figure 1 Figure 2
Figure 1: Correct way to duct plenum off of air handler whenever possible
in a new installation.
Figure 2: Incorrect way to duct plenum off of air handler.

10
Figure 3 Figure 4
Figure 3: Correct way to install duct work.
Figure 4: Incorrect way to install duct work

11
Typical Air Handler Schematic

12
THERMOSTAT SELECTION
Most standard 24VAC thermostats will work with the Enerzone CAH EC
Motor air handlers.
POWER SUPPLY: NON-POWER STEALING (Battery or 24 VAC
Voltage supply)
DISPLAY: ANALOG OR DIGITAL with or without
programmable set points.
NOTE : ENERZONE recommends hard wiring the thermostat to run off
the 24VAC transformer in place of using POWER STEALING
THERMOSTATS.
SELECTING FAN SPEEDS
Blower motor torque settings are
selected by moving the wires on the
motor tap selection tree located in the
blower mounted electrical box.
Use the Blower Motor Wire Selection
Chart in this manual to select the
proper wires for your application
HEAT / COOL FAN SPEED –select the appropriate motor tap wire to
plug into this terminal. This is the speed the motor will run for both
heating and cooling.
LOW CONTINUOUS FAN: select the appropriate motor tap wire to plug
into this terminal. This is the speed the motor will run when the
thermostat Fan switch is set to the ON position.
SPARE: Plug any unused motor tap wires onto this terminal.

13
BLOWER MOTOR WIRE SELECTION CHART
AIR HANDLER
MODEL
CAH 33-44-50
CAH 49-54-70
RED/TRACE
LOW CONTINUOUS
SPEED
LOW CONTINUOUS
SPEED
YELLOW/TRACE
600 CFM
1000 CFM
BLUE/TRACE
800 CFM
1200 CFM
PURPLE/TRACE
800 CFM BOOST
1200 CFM BOOST
BLACK/TRACE
1000 CFM
1600 CFM
EXAMPLE:
Model CAH 33-44-50
Blue/Trace wire onto the heat / cool fan speed Terminal
Unit will run at 800 cfm for both heating and cooling
(@0.4” external static)

14
HOT WATER COIL PIPING
The water coil connections are:
½” nominal (5/8”OD) copper on all models with internal pump factory
installed.
An air purge valve must be installed between the air handler outlet and the
return water isolation valve.
Flow stickers indicate the proper water flow direction.
Isolation valves must be placed in both the hot water supply and return
water lines to the hot water tank so that the CAH unit may be serviced or
repaired without causing excessive water discharge. All piping between
the water heater and the air handler should be copper and should never
exceed 100 feet of total equivalent piping. On runs over 60 feet
equivalent, it is recommended that ¾” nominal (7/8” OD) piping be used
to prevent excessive system pressure drop. Vertical rises should be kept
as short as possible. Where extended runs or large vertical rises are
required (greater than 5 feet) it is recommended that the installer consult
the factory for proper installation practices.
NOTE: It is not recommended to locate water piping in unconditioned
spaces.
All copper joints in the water lines must be made with low temperature,
non-lead solder. Due to the use of domestic hot water in the units, all
local and national plumbing codes relating to potable water must be
complied with for proper installation.

15
OPERATION AND MAINTENANCE
INITIAL START-UP
THE “DO’S AND DON’TS” PAGES ARE AN INTEGRAL PART
OF THE INSTALLATION INSTRUCTIONS. IT MUST BE READ
AND THOROUGHLY UNDERSTOOD PRIOR TO
ATTEMPTING TO INSTALL CAH AIR HANDLERS
Prior to start-up, inspect the blower to confirm the blower wheel turns
freely without interfering with the housing. Replace the service access
panel.
Note: The service access panel must be in place for the unit to operate
due to the “door switch”, which interrupts the power supply when the
access panel is not in place.
WARNING
To prevent pump damage, the air handler should not be operated
in heating mode until the user supplied/installed isolation valves have
been opened and the hot water coil and hot water lines have been purged
of air.
Heating Mode –Initial Operation
1. Fill the water heater (refer to water heater instruction). Open a
domestic hot water faucet while filling the water heater to vent
the air. When the tank is full and all of the air is purged close the
faucet.
2. Ignite the water heater (see water heater instructions) and set the
thermostat to 140 °F nominally, but never higher than 180 °F as
this is the maximum temperature this air handler is designed to
accommodate.
3. Purge the air from the hot water coil and the lines. Located inside
of each CAH hot water fan coil is an air purge valve. This valve
is necessary to enable air to be evacuated from the water lines.

16
To purge the air from the system once your installation is
complete do the following steps:
(A) Attach a hose to the air purge valve and run the hose to a
bucket or drain. This hose is a modified refrigeration
Schrader valve charging hose.
(B) Close the isolation valves on the hot water supply and
return.
(D) Open the hot water supply isolation valve and let the
water flow until all air is evacuated.
(E) Open the hot water return isolation valve and let the
water flow until all air is evacuated.
(F) All air is now purged from the system.
(G) Remove the hose to close off the air purge valve and
replace the brass cap.
(H) Open the hot water supply and return isolation valves to
allow water to flow through the system.
Note: it will often require purging several gallons of water so
either have a bucket available or an alternate means of discarding the
water.
4. Switch the room thermostat to the “heat” position and raise the
temperature setting to a position approximately five to ten
degrees above the room temperature. Note: The door switch
must be activated to operate the unit. The pump will energize
and begin circulating hot water through the coil. If the pump is
operating properly and the water temperature in the water heater
has reached the set point, then the hot water inlet at the fan coil
unit will be approximately the same temperature as the water
heater setting. If the pump is running but the hot water is not
circulating, repeat step 3 (purging air out of system).

17
5. The thermostat on the water heater should be adjusted so that the
water temperature entering the hot water coil is nominally at 140
°F (See DO’S and DON’TS section for mixing valve
requirement for higher temperatures), depending upon unit
selection temperature. Allow the system to operate long enough
for all temperatures to stabilize and recheck temperature setting.
Remember that the domestic supply water temperature should be
kept to 120 °F or lower by means of an appropriate mixing valve.

18
AIR FILTER
The air filter should be cleaned as often as necessary to prevent
restriction of air flow (every three months under normal conditions).
Always replace the filter with the same type as originally furnished.
BLOWER MOTOR
The Variable speed motor has sealed bearings and routine oiling is
not required or possible. The motor may be wiped down with a cloth or
blown out to remove any accumulated dirt and dust to help the motor cool.
To remove the blower and motor:
-turn off all power to the air handler.
-Disconnect the thermostat wiring from the 5 position terminal strip
on the blower mounted electrical box.
-Unplug the power supply MOLEX terminal from the top of the
blower mounted electrical box.
-Remove the two blower mount screws and slide blower and motor
from the unit.
CIRCULATION PUMP REPLACEMENT
Disconnect electrical power before servicing the unit.
To replace the circulating pump, close the isolation valves and relieve the
water pressure from within the heating loop. Remove the four hex head
screws that secure the pump head to its volute. Disconnect the pump’s
115VAC power lines from within the electrical control box and remove
the pump from the unit.
Reverse the above steps for re-assembly of the pump. Refer to initial
start-up procedure for instructions regarding purging air from the system.

19
PUMP CONTROL:
LOW VOLTAGE CONTROL BOARD
During the heating season the pump is controlled by the low voltage
circuit control board.
The control board also operates as an off season pump circulator to
eliminate stagnant water in the heat exchanger. This pump cycle will
operate for 1 minute every 12 hours after the last call for heat.
SEQUENCE OF OPERATION IN HEATING MODE:
1. When the thermostat calls for heat (W) the pump and blower motor
will run at the selected operating fan speed.
2. When the thermostat ends the call for heat (W) the pump and
blower turn off. The blower will continue running at the
continuous low speed if the thermostat is set to FAN-ON.
Note: Upon powering up
the air handler circuit
board starts a 15 second
initialization during which
the pump operates for 5
seconds.
Circuit board LED
illuminates when the
pump is operating during
heating and pump purge
cycles.

20
TROUBLESHOOTING
MOST LIKELY PROBLEMS AND CAUSES
Important: For system to operate properly power should be turned ON
and all shut-off valves/isolation valves must be open.
If Pump Does Not Run:
1. Circuit board controls operation of pump.
Check that pump LED is illuminated.
Check for 24VAC at pump terminal on circuit board.
If faulty refer to “Faulty Circuit Board” section.
2. Check line voltage wiring to pump. Check for 120 VAC at
pump relay and inside the pump electrical box.
Pump is Noisy:
Air may be trapped in the water circuit. Purge air from the system as
described under “start-up procedure”.
Insufficient or No Heat:
1. Air may still be trapped in heating loop. Purge air from the
system as described under “start-up procedure”.
2. Water heater thermostat not turned up high enough.
(Remember, higher than 120 °F = mixing valve for domestic
service).
3. Inlet and outlet piping connection at the air handler may be
reversed. See “Hot Water Piping”).
4. Water heater thermostat not calibrated properly.
5. Excessive pressure drop caused by restriction somewhere in the
hot water loop does not allow sufficient water to flow to air
handler.
6. Air handler not sized large enough for heat load.
7. Water heater not large enough to satisfy heat load.