Recirculation Mode - Giant Factories ANSI Z21.10.3 Owner's Manual

Recirculation Mode

The Giant water heater has the ability to control a recirculation
pump. Two modes are available, Economy and Comfort, which re-
circulate the water in the plumbing system to provide hot water
more quickly when a tap is opened.
Recirculation mode is for residential installations only. Recircu-
lation mode cannot be used with an air handler or with multiple
CONDUITE D'ALIMENTATION
COLD WATER SUPPLY LINE
EN EAU FROIDE
Giant water heaters.
The maximum Giant temperature setting while in recirculation
CHECK
CLAPET
ANTI-RETOUR
E- VALVE
mode is 140°F (60°C).
AL
RÉSERVOIR
THERMAL
UE
ON
EXPANSION THERMIQUE
Pump Requirements EXPANSION TANK
)
Voltage: 120V, 60 Hz CLAPET ANTI-RETOUR
Amperage: less than 2 amps
NOTE: The Giant PC board will be damaged if amperage ex-
ceeds 2 Amps.
CONDUITE DE
In-rush current: Less than 2.5 Amps.
RETOUR
(minimum 3/4")
Check valve: An integral flow check (IFC) valve is required. See
plumbing diagram.
Pump Size
de plomberie
The pump should be sized for 2.5 GPM at the pressure loss through
the tankless water heater and the supply and return plumbing in
the recirculation loop.
Installation
1) Turn off the electrical power supply by unplugging the power
Coupez le
cord or by turning off the electricity at the circuit breaker.
connecteur
raccordez les ls
2) Install the recirculation pump on the return line according
Fusible 4
ampères to the pump manufacturer's installation instructions. Install
Bleu
a check valve in the return line as shown in the Plumbing
POMPE PUMP
Diagram if one is not integrated into the pump.
Blanc
3) The wire harness for the recirculation pump is bundled with
the wire harness from the PC board. The connector has a
Raccordement électrique de la pompe
black and white wire with the label "Cut wire to connect to
pump". To do so, cut the connector, splice the wires, and
add 4-Amp fuse to the hot wire (black) of the pump. Connect
the ground wire from the pump to a screw at the base of
the water cabinet. Refer to the Pump Electrical Connection
Diagram. Follow Electrical Code and pump manufacturer's
recommendations.
4) Adjust the dip switch by moving the switch # 4 in the white
set of switches (SW2) to ON. For Economy mode, set the
switch # 8 in the white set of switches (SW2) to OFF (default).
For Comfort mode, set the switch # 8 in the white set of
switches (SW2) to ON.
5) Connect power to the water heater. Press the Power button
on the controller. The pump and water heater will turn on to
raise the recirculation loop temperature.
Table 25
Economy Mode
Comfort Mode
TECHNICAL DATA
Carte de
circuit
imprimé
Settings for SW2
(bank of white switches)
Switch # 4 Switch # 8
ON OFF
ON ON
Figure 40
POWER FOR
WATER HEATER
HOT WATER
SUPPLY LINE
POWER FOR TIMER
(minimum 3/4")
ELECTRICAL
CONNECTION
(POWER)
RECIRCULATION
LOOP
HOT WATER OUTLETS
Plumbing Diagram
Figure 41
4 Amp
Fuse
PUMP
Pump Electrical Connec on
Sequence of Operation
DIP switches (SW2 - white switches, #4, #8) should be set cor-
rectly for recirculation and mode. The Giant water heater should
be turned on.
Pump recirculation begins when the water heater is turned on. The
Giant inlet and outlet thermistors measure the water temperature.
The water heater produces hot water at the temperature setting. If
the inlet thermistor detects abnormal temperature, then diagnostic
code 51 is generated and the pump will turn off.
When the return water temperature reaches approximately 15°F
(8.3°C) below the temperature setting, the water heater and pump
will turn off.
The cycle will restart at the approximate time interval in the table
based on the temperature thermistor readings.
Economy Mode
The Economy mode operates as follows:
• Less energy consumed due to fewer pump cycles
• Assumes plumbing is insulated (minimal pipe heat loss)
• Pump cycles on every 31 to 79 minutes (see table).
38
COLD WATER SUPPLY LINE
CHECK
VALVE
THERMAL
EXPANSION TANK
CHECK VALVE
RETURN LINE
(minimum 3/4")
Cut connector
PC
and splice wires.
Board
BL
W