Waiwela WET-12 T User manual

ELECTRIC INSTANTANEOUS WATER HEATER
INSTALLATION GUIDE AND OWNERS MANUAL
IF YOU REQUIRE ANY HELP OR HAVE ANY QUESTIONS RELATING TO THE
INSTALLATION OR PERFORMANCE OF THIS HEATER, PLEASE CALL OUR
TECHNICAL SERVICE DEPARTMENT TOLLFREE : 1-800-543-6163.
HAVE THE INFORMATION LISTED BELOW BEFORE CALLING :
SERIAL NO. MODEL NO. WET-12 INSTALLATION DATE
WAIWELA “SERIES-TWO” WATER HEATERS
MODELS COVERED – WET-12 T, TC, T2 - 240/208 V
SPECIAL_________,______V
READ THE GENERAL SAFETY SECTION BEGINNING ON THE INSIDE COVER
AND THEN THIS ENTIRE MANUAL BEFORE INSTALLING OR OPERATING THIS
WATER HEATER. IF YOU DON’T FOLLOW THE SAFETY RULES, THE UNIT WILL
NOT OPERATE PROPERLY AND IT COULD CAUSE DEATH, SERIOUS BODILY
INJURY AND/OR PROPERTY DAMAGE. READ ALSO THE ENCLOSED
WARRANTY CARD. WARRANTY OF THIS WATER HEATER WILL DEPEND ON
PROPER INSTALLATION AND OPERATION. THE WARRANTY SHALL BE VOID IF
THE DESIGN HAS BEEN ALTERED IN ANY WAY WHATSOEVER. THE
MANUFACTURER OF THIS HEATER WILL NOT BE LIABLE FOR ANY DAMAGES
BECAUSE OF FAILURE TO COMPLY WITH THE INSTALLATION AND
OPERATING INSTRUCTIONS OUTLINED ON THE FOLLOWING PAGES.
THE INSTALLATION MUST CONFORM WITH THE INSTRUCTIONS IN THIS
MANUAL; ELECTRIC COMPANY RULES; AND THE LOCAL CODES, OR IN
THE ABSENCE OF LOCAL CODES, WITH THE LATEST EDITION OF THE
NATIONAL ELECTRICAL CODE. THIS PUBLICATION IS AVAILABLE FROM
YOUR LOCAL GOVERNMENT OR PUBLIC LIBRARY OR ELECTRIC COMPANY
OR BY WRITING UNDERWRITERS LABORATORIES, 333 PFINGSTEN ROAD
NORTHBROOK, IL, 60062.
WARNING
19/23/2008

GENERAL SAFETY
The “WaiWela Series Two” heater is specifically designed to take in cold water and heat it to
temperatures suitable for normal domestic usage up to a maximum of 125° F (52° C). To
obtain optimum performance and energy savings, the unit should be located as near as
possible to the point of use.
The unit is supplied with 3/4” NPT pipe connections. Under no circumstances use a blow
torch on pipe which is connected to the heater (serious damage to the electronic flow
switch will result). Carefully use Teflon tape, ensuring no debris enter the heater. Do not
use pipe dope.
Also, ensure that the pipes are clear of installation debris before fitting the heater.
THIS HEATER MUST HAVE ONE DEDICATED INDEPENDENT
CIRCUIT, USING CORRECTLY RATED WIRES AND CIRCUIT
BREAKER.
WARNING
IMPROPER INSTALLATION, ADJUSTMENT, ALTERATION, SERVICE OR MAINTENANCE
CAN CAUSE DEATH, SERIOUS BODILY INJURY OR PROPERTY DAMAGE. REFER TO
THIS MANUAL FOR ASSISTANCE OR CONSULT THE LOCAL ELECTRIC UTILITY FOR
FURTHER INFORMATION.
FAILURE TO GROUND THE SYSTEM MAY RESULT IN DEATH OR SERIOUS INJURY.
WARNING
WARNING
WATER HEATERS EQUIPPED FOR ONE VOLTAGE ONLY: THIS WATER HEATER IS
EQUIPPED FOR ONE VOLTAGE TYPE ONLY: CHECK THE RATING PLATE ON THE FRONT
COVER OF UNIT FOR THE CORRECT VOLTAGE. DO NOT USE THIS WATER HEATER WITH
ANY OTHER VOLTAGE OTHER THAN THE ONE SHOWN ON THE MODEL RATING PLATE.
FAILURE TO USE THE CORRECT VOLTAGE CAN CAUSE PROBLEMS WHICH CAN RESULT
IN DEATH, SERIOUS BODILY INJURY, OR PROPERTY DAMAGE. IF YOU HAVE ANY
QUESTIONS OR DOUBTS CONSULT WAIWELA OR YOUR ELECTRIC COMPANY.
WARNING
HAZARD OF ELECTRICAL SHOCK! BEFORE REMOVING THE COVER OR SERVICING THE
WATER HEATER, MAKE SURE THE ELECTRICAL SUPPLY TO THE WATER HEATER IS
TURNED “OFF”. FAILURE TO DO THIS COULD RESULT IN DEATH, SERIOUS BODILY INJURY,
OR PROPERTY DAMAGE.
2

MINIMUM - 8” CLEARANCE ABOVE UNIT
3
Figure 1
MOUNTING
HOLES
To independent
circuit breaker
serial #
LUG
TERMINALS
AT RELAYS
ELECTRICAL
HOOK-UP
240V/208V
L1 L2 L1 L2
GROUND
LUG
Factory installed jumpers from
L1 –L1 and L2 – L2

I. MOUNTING THE UNIT
1) The unit should be mounted as close to the point of use as possible. For example, directly
beneath the sink is ideal.
Do not install the heater above a faucet or “point of use” because the siphoning effect may
drain the heater which can cause premature element burn out.
2) This unit must only be mounted in a vertical position with the water fittings located at the
bottom of the unit. Mounting other than in the vertical position WILL cause element burn
out and cause permanent damage to the water heater.
3) The cold water inlet is on the right hand side and the hot water outlet is on the left hand side.
Under NO circumstances can these be reversed.
4) Leave a minimum of 8” above the unit for easy replacement of the element.
5) The heater should be fixed to the wall using screws in the four mounting holes at each corner
of the backplate.
NOTE: The heater should be installed below the level of all hot water outlets serviced by this
heater.
NOTE: PRESSURE AND TEMPERATURE RELIEF VALVE
These units are not required by UL to have a Pressure and Temperature Relief
Valve (PTRV). You should check with local codes to find out if one is required in your
area.
If local codes require the use of a temperature and pressure relief valve it should be
installed on the outlet hot water pipe before the outlet ball valve.
Cold
Installation directly beneath the
sink is ideal
WaiWela
Figure 2 Hot
4
TO SHOWER
HOT OUTLET COLD INLET

II. PLUMBING HOOK-UP
1) The unit is supplied with ¾’’ NPT fittings (Figure 3), USE THESE. DO NOT USE
PIPE DOPE AND DO NOT SOLDER TO THE INLET OR OUTLET.
2) Take care to ensure that the pipes are correctly aligned with the inlet and outlet bosses
in order to avoid excessive stress on the heater body molding.
NOTE: When soldering pipe joints remove heater from the wall. Serious damage can occur
if any soldering is done while pipes are connected to the heater.
Run water through the supply pipe to remove all debris from the pipe before connecting
the heater. Failure to do so could cause damage to the flow switch.
3) Install isolating valves (full flow ball valve type) on both inlet and outlet pipes. This allows unit
to be isolated for maintenance purposes. (Fig. 1)
4) When all plumbing is complete, fully check the system for water leaks at all the plumbing
connections. If a leak is present take corrective action. If
the leak is at a compression fitting, slowly
tighten the compression nut until it stops. Fully open both inlet and outlet BALL VALVES.
Run all the hot water outlets fed by this heater one at a time, for a minute or two, until the water
flow is continuous, free from “gulping” and from all visible air pockets.
HOT OUTLET
¾’’ NPT
FITTING
DO NOT SOLDER
COLD INLET
¾’’ NPT
FITTING
DO NOT SOLDER
NOTE:
ALL MOUNTING AND PLUMBING MUST BE COMPLETE BEFORE YOU
PROCEED WITH ELECTRICAL HOOK-UP.
TEST THE INSTALLATION FOR LEAKS BEFORE CONNECTING THE
ELECTRICAL SUPPLY.
4”
Figure 3
5

III. ELECTRICAL HOOK-UP
WARNING
BEFORE BEGINNING ANY WORK ON THE ELECTRICAL INSTALLATION,
BE SURE THE SWITCH AT MAIN BREAKER PANEL IS “OFF” TO AVOID
ANY DANGER OF ELECTRICAL SHOCK.
“Series-two” heaters are manufactured to the following specifications:
This unit must have its own independent circuit, using 1 SET of UL listed 2 conductor and
ground core copper wire cable of the appropriate size protected by 1 independent
correctly rated Double Pole breaker. (208, 220, 240 V, see Figures 4 and 5).
Wire entry into the unit must be made through the hole provided in the flange on the backplate.
The “live” wires should be connected to the slots in the terminal block marked L1 and L2. The
ground lead must be connected to the slot marked GND.
GROUND MUST BE BROUGHT TO THE “GROUND” AT THE CIRCUIT BREAKER PANEL.
DANGER
FAILURE TO GROUND THE SYSTEM MAY RESULT IN DEATH OR SERIOUS INJURY.
* Units rated for 240 V can operate at 220 V or 208V with reduced output.
The output will vary in accordance with the following ratios:
208 volts 220 volts 240 volts
.75 .84 1.0output ratio
volts
MODEL TYPE OUTPUT / kW VOLTAGE / V AMPERAGE
EX 120 11.5 *240 47.9 Amps
SPECIAL
ONON OFFOFF
1 independent
correctly rated Double pole
breaker (240/208 Volts)
Figure 4
Figure 5
6
Circuit Breaker Panel

IMPORTANT
BEFORE SWITCHING “ON” THE POWER AT THE MAIN CIRCUIT BREAKER PANEL
MAKE SURE THAT THE HOT WATER CIRCUIT IS FREE OF AIR POCKETS OR ELSE
PREMATURE FAILURE OF THE ELEMENT WILL OCCUR. TO DO THIS OPEN ALL HOT
WATER OUTLETS ONE AT A TIME FOR A MINUTE OR TWO UNTIL THE WATER FLOW
IS CONTINUOUS AND FREE FROM “GULPING” AND FREE FROM VISIBLE AIR POCKETS.
1) Open fully both inlet and outlet valves at the heater.
2) Open any hot water outlet in the system. If the outlet is a “single lever” mixer type turn to the
hottest position. Run for one minute to clear all the air from the system.
3) Slowly close OUTLET ball valve until the water flow from the faucet just starts to reduce.
NOTE: This process has two effects. One, any air in the system will be purged out. Two, the
heater units will be pressurized at the supply pressure. This will prevent the elements burning
when energized.(Note: Keep water flowing whilst carrying out the procedures outlined below.)
GO TO APPROPRIATE SECTION FOR YOUR MODEL
NOTE: For the following sections the first unit is the right hand heating module and the second
unit is the left hand heating module.
IV. COMMISSIONING YOUR HEATER
“T” MODELS
a) Switch on the power to the first unit. The power indicator light should illuminate.
b) Switch on the power to the second unit, again the power indicator light should illuminate.
Note: This light should pulse On and Off at first and after about 20 - 30 seconds it should
stay fully on.
c) Use the OUTLET ball valve to gradually reduce the water flow until the power indicator light
on the second unit begins to pulsate. The water temperature should now be approximately
125° F.
d) The thermostat is now set and the water temperature will always be the same when the
indicator light is pulsing.
e) Increasing water flow (above the flow rate at which the thermostatic control is no longer
effective) will reduce the water temperature.
“P2” MODELS
a) Switch on the power to the first unit. The power indicator light should illuminate.
b) Switch on the power to the second unit, again the power indicator light should illuminate.
c) Temperature is controlled on this unit by controlling the amount of water flowing through it.
e.g. The higher the water flow rate the lower the water temperature and vice-versa.
7

“TC and T2” MODELS
a) Switch on the power to the unit, the power indicator light should illuminate.
Note: This light should pulse On and Off at first and after about 20- 30 seconds it should
stay fully on.
b) Use the OUTLET ball valve to gradually reduce the water flow until the power indicator lights
on both units begin to pulsate. The water temperature should now be approximately
125° F.
For “T” , “TC”, and “T2” Models
If a lower temperature is required, turn the temperature adjustment screw(s) counter-clockwise
about 1/8 of a turn (See Figure 1). Wait 15-20 seconds and check the temperature at the fixture.
Repeat this process until the desired temperature has been achieved. (For T2 models try to adjust
both temperature adjustment screws by about the same amount so that the lights pulse at the same
rate.) If you have reduced the temperature considerably from the 125° F setting, you could now
open up the outlet ball valve slightly to achieve a higher rate of flow.
When the indicator light is on continuously, the unit is emitting full power. When it is pulsing, the
unit is modulating the power to achieve the temperature set by means of the temperature
adjustment screw.
ALL HEATERS
In order to obtain good control at “single lever” mixer type faucets (single spout) the cold water
supply to the faucet should be restricted to give approximately the same flow rate of cold water
to the faucet as the hot water coming from your WaiWela heater. The simplest method of doing
this is by partially closing the cold water valve under the sink.
MAXIMUM TEMPERATURE RISE CHART ( 0F )
OUTPUT 0.75 1 1.25 1.5 2 2.5 3
11.5 kW 104 78 62 52 39 31 26
8

TROUBLESHOOTING
SYMPTOM “A”: NO HEAT - INDICATOR LIGHT OFF
1) ELECTRIC SUPPLY IS OFF
Turn on the main circuit breaker.
2) NO OR LOW WATER FLOW
Ensure that the minimum flow rate to switch on your heater is met.
T, TC Models – 0.75gpm
T2 Models – 1.5gpm
P2 Models – 1.5gpm
Also check that the inlet filter screen is clear from any
debris. This is located in the brass inlet boss.
3) WATER CONNECTIONS ARE REVERSED
Cold water inlet = right side, hot water outlet = left side.
4) ELEMENT BURNED OUT
TURN OFF THE MAIN CIRCUIT BREAKER!
Using an ohmmeter test the resistance of the heating element
across the two threaded termination rods on top of the element.
The resistance reading should be under 10 ohms. If the resistance
is much greater than this value, call Waiwela for a replacement element.
5) ECO TRIPPED (High Limit Thermostat)
TURN OFF THE MAIN CIRCUIT BREAKER!
Reset by pushing in red button on each heater module.
SYMPTOM “B”: NO HEAT OR LOW TEMPERATURE WITH INDICATOR LIGHT ON
1) WATER FLOW TOO HIGH
Reduce the water flow by using an outlet ball valve. See page 8 for temperature rise at various
flow rates.
2) INCORRECT POWER SUPPLY
Make sure that the unit is connected to the voltage supply specified on the rating label on the
front cover of the unit and no other.
3) ELEMENT BURNED OUT
TURN OFF THE MAIN CIRCUIT BREAKER!
Repeat the steps from paragraph 4 above.
4)THERMOSTAT ADJUSTMENT SCREW NOT TURNED UP (Models “T”, “TC” and “T2” only.)
Turn both thermostat adjustment screws clockwise in small increments until the indicator light(s)
remains on. Take care not to force the screw past it’s stop position.
5) ECO TRIPPED (High Limit Thermostat)
See Paragraph 5 above.
9

Inlet isolating valve-
ball valve. (Always leave fully
open when unit is in service.)
REPLACEMENT HEATER
CORE ASSEMBLY
EX1000 – 5.75KW @240V
7 - Wire
EX 100G
8 - Wire
EX 284
WaiWela, 5350 Joliet St. #2 Denver, CO 80239 Tel: [phone]
To appropriate
circuit breaker
10
Triac - EX 18
WAIWELA REPLACEMENT PARTS DIAGRAM
CONTROL BOARDS
serial #
ECO (High Limit Thermostat)
Push to Reset
L1 L2
Temperature Adjustment Knob
L1 L2
To 2nd
module

6 – Wire + T/C
EX 284
EL/L (BLK) ELEMENT RING
TRIAC (BLK)
RELAY (ORG) TO ECO
7 - Wire
EX 100G
EL/L1 (BLK) ELEMENT RING
TRIAC GATE (BLK) POWER (BLK) L1 FROM RELAY LINE SIDE
T/C (BLU) T/C (BLU)
RELAY (ORG) TO ECO
EL/L2-N (RED or WHT) ELEMENT RING
T/C (BLU) 2 PIN CONNECTOR
RELAY (ORG) TO RELAY COIL
L1 POWER (BLK) FROM RELAY LINE SIDE
L2-N POWER (RED/WHT) FROM RELAY LINE SIDE
CIRCUIT BOARD DIAGRAM
11