Solar Water Heater With Electric Backup
Solar Saver® Heaters
SERVICE
MANUAL
Troubleshooting Guide
and Instructions for Service
(To be performed ONLY by
qualified service providers)
Models Covered
by This Manual:
S-SW2-60R6DS
S-SW2-75R6DS
S-SW2-115R6DS
Manual 238-47297-00A
Save this manual for future reference
GENERAL INFORMATION
Commonly Used Formulas
Single Phase Amps = Watts Example 4500W/240V = 18.75A
Volts
Watts = Amps x Volts
Example 18.75A x 240V = 4500W
2
Ohms = Volts2
Watts
Example (240V) / 4500W = 12.8 Ohms
Service Wire Configuration
240 VOLT
BLACK
GREEN
RED
Grounding
Ungrounded
Ungrounded
240
120
120
Wattage Limitation at 240 Volts
Solar Water Heater with Double Electric Element Backup Series (Non-Simultaneous operation)
Maximum
Wattage
Element
Upper/Lower
5,500/5,500
5,500
3
GENERAL INFORMATION
Surface Mounted Thermostats
Surface mounted thermostats are mounted into a bracket which holds the thermostat against the side of the tank.
Surface mounted thermostats respond to tank surface temperatures to sense a call for heat, set point temperature
settings and high limit (ECO) activation. It is important that the entire back surface of the thermostat is in full contact or
flush with the tank. Improperly mounted thermostat will lead to improper heater operation.
Manual
ECO (high limit)
Reset button
Temperature
control Dial
Upper thermostat
Surface Mount
With
ECO (high limit)
89T Series
Lower thermostat
Surface Mount
59T Series
Direct Immersion “Screw-in” Type Heating Element
1-½ Hex
Screw-in Flange
Terminal Block
Zinc Incoloy Sheath
Terminal Block
Screw
Element Rating Ink Stamped
on side of Terminal Block.
4
SEQUENCE OF OPERATION
Non-Simultaneous Operation
Non-Simultaneous Mode: Allows only one heating element to operate at a time. For example, when the tank is cold,
the upper element is energized first, heating the top of the tank. Only when the upper thermostat is satisfied, the upper
element is de-energized and power is directed to the lower thermostat, energizing the lower element and heating the
bottom portion of the tank until the lower thermostat is satisfied. As hot water is drawn off the tank, it is replaced with
cold water delivered through the dip tube to the bottom of the tank. When the tank cools at the lower thermostat level,
the thermostat will call for heat energizing the lower element. If enough hot water is drawn from the tank, the top portion
of the tank cools and the upper thermostat will call for heat, de-energizing the lower element and allowing only the top
element to energize until the upper thermostat is satisfied.
The lower thermostat in the solar water heater is located above the internal heat exchanger. This design allows the heat
exchanger to be in cooler water during short draws, providing more heat transfer from the solar heating system.
Solar water heaters with double electric element backup are designed to operate using a single operating mode detailed
as follows:
Sequence of Operation- Double Element, Non-Simultaneous Operation, Single Phase.
1
Line voltage is applied across terminals
L1 & L3 of the upper thermostat. ECO is
closed, so there is voltage at terminal L4
and to one side of the upper and lower
elements.
1
2
2
Tank is cold. Therefore, the thermostats are closed
at terminals T2 & 2 (calling for heat). The circuit is
complete through the upper thermostat only,
ECO
Closed
Thermostat closed
at terminal T2
allowing current to flow through the upper element.
Upper
T’stat
Upper
T’stat
When the upper thermostat is satisfied, it opens at
terminal T2, interrupting current flow through the
upper element. Terminal T4 closes, allowing voltage
to pass to terminal 1 of the lower thermostat. This
completes the circuit through the lower thermostat
and allows current flow through the lower element.
3
Upper
Element
Upper
Element
Thermostat closed
at terminal 2
Lower
T’stat
Lower
T’stat
4
5
When the lower thermostat is satisfied, it opens at
terminal 2, interrupting current flow through the
lower element. The system is now in stand-by mode
waiting for the next call for heat
Lower
Lower
Element
Element
The lower thermostat/element
combination will generally
3
4
5
cycle on and off more often
then the upper. In some cases,
such as a cold tank or in high
demand periods, the
Thermostat closed
Thermostat closed
upper thermostat will
at terminal T4
at terminal T2
call for heat (opening at
Upper
T’stat
Upper
T’stat
Upper
T’stat
terminal T4 and closing at
terminal T2) prior to the lower
thermostat being satisfied. This
will interrupt current flow
Upper
Element
Upper
Upper
Element
through the lower thermostat
Element
and element and allow current
to flow through the upper
Thermostat open
between terminals
1 and 2
Thermostat closed
between terminals
1 and 2
element only. When the upper
Lower
T’stat
Lower
T’stat
Lower
T’stat
thermostat is satisfied, it
resumes operation as
Lower
Element
described in sequence #3
Lower
Element
Lower
Element
above.
5
TROUBLESHOOTING
NOTICE
This Service Manual is for servicing the solar water heater. If other components of an
installed system requires service, those questions should be directed to the installer or
the specific component manufacturer.
Most common cause for improper electric backup operation can be linked to heating element failure.
When troubleshooting an electric backup solar water heater with the incidence of “No Hot Water” or “Insufficient Amount
of Hot Water”, it’s always a good idea to check the heating elements first following the procedure on page 9.
Common Heating Element Failures Are:
1. Dry Firing. Element may be partially submerged in water or most likely, completely exposed with no water in
the tank. In some cases sediment or lime build up around an element can eventually cause an air pocket, and
within seconds, result in a dry-fired element. At this point the element becomes inoperative. When element
replacement is required, be sure the tank is full of water prior to energizing the water heater.
2. Grounded Element. An element with a short circuit to ground will in most cases cause the circuit breaker in
the service panel to open or shut off. In some cases there may not be enough current draw for the circuit
breaker to open. This will allow the heating element to be in continuous operation resulting in over-heated
water, limited only by the ECO (Energy Cut Off) located in the thermostat. Repeated actuation of the ECO
reset button on the thermostat usually is the result of a grounded element.
3. Sediment build up. Slow hot water recovery can usually be traced back to sediment or lime build up around
the heating element. Sediment build up can also over time cause a dry-fired element.
Illustration 1, below shows a common “Screw-In” type heating element identifying certain features commonly referred
to throughout this manual.
1-½ Hex
Screw-in Flange
Terminal Block
Zinc Plated Incoloy Sheath
Terminal Block
Screw
Element Rating Ink Stamped
on side of Terminal Block.
Illustration 1
Typical Direct Immersion “Screw-In”
Type Heating Element
6
TROUBLESHOOTING
WARNING
Quick Step Plan to Hot Water
1. TURN OFF power to water heater and solar controller.
Check all wire connections to insure they are tight and
corrosion free.
High voltage exposure. Use caution when
making voltage checks to avoid personal injury.
NOTICE
This Service Manual is for servicing the solar water heater.
If other components of an installed system requires
service, those questions should be directed to the installer
or the specific component manufacturer.
2. Turn power “ON” and determine that service voltage is
present and the high limit (ECO) has not actuated
(see procedure on page 8).
3. Check for inoperative heating element (see procedure on page 9).
4. Check for proper thermostat operation (see procedures beginning on page 10). NOTE: Thermostat testing procedures
assume items 2 and 3 above are in working order.
SERVICE
CORRECTIVE ACTION
SYMPTOM
PROBABLE CAUSE
PROCEDURE
3. See Service Procedure
RE-II, Page 9.
4. See Service Procedure
RE-III, Page 10.
5. See Service Procedure
RE-I, Page 8.
6. Refer to Controller
manufacturer
1. No Power to heater.
2. Loose wire connections.
3. Inoperative upper heating element.
4. Inoperative upper thermostat.
5. Open ECO.
6. Inoperative solar controller or
connection.
1. Check fuses or circuit breakers in service panel.
2. Check all wire connections.
3. Check heating elements. Replace as needed.
4. Check thermostats operation. Replace as
needed.
5. Check ECO. Reset or replace thermostats as
needed.
6. Check for proper solar controller operation.
7. Check for proper circulator operation.
No Hot Water
7. Inoperative circulator in solar heating
system.
7. Refer to circulator
manufacturer
1. Check heating elements, replace as needed.
2. Increase thermostat setting.
3. Check thermostats, replace as needed.
4. Check all wire connection.
5. Remove heating elements and check for lime
build up.
1. Inoperative lower heating element.
2. Thermostats set to low.
1. See Service Procedure
RE-II, Page 9.
3. See Service Procedure
RE-III, Page 10.
5. See Service Procedure
RE-V, Page 13.
10. See Service Procedure
RE-VI, Page 14.
3. Inoperative thermostats.
4. Loose wire connection.
5. Sediment or lime build up on elements.
6. High demand period.
Not Enough Hot
Water
6. Reduce demand.
7. Undersized heater.
7. Replace with larger heater.
8. Temper water to heater.
9. Correct plumbing connections.
10. Check dip tube, replace as needed.
11. Review solar collector calculations and
orientation.
8. Very cold inlet water to heater.
9. Plumbing connections reversed.
10. Damaged dip tube.
11. Refer to solar collector
manufacturer.
11. Improper solar collector application.
1. Remove heating elements and check for
lime build up.
1. Sediment or lime build up on elements.
2. Loose wire connections.
1. See Service Procedure
RE-V, Page 13.
3. See Service Procedure
RE-III, Page 10.
Slow Hot Water
Recovery
2. Check all wire connections.
3. Inoperative thermostats.
3. Check thermostats, replace as needed.
4. Check terminal block of element for proper
voltage and wattage rating.
4. Derated heating element installed.
1. See Service Procedure
RE-IV, Page 12.
2. See Service Procedure
RE-II, Page 9.
4. See Service Procedure
RE-III, Page 10.
5. See Service Procedure
RE-I, Page 8.
1. Thermostat not in contact with tank.
2. Grounded heating elements.
3. Thermostat set to high.
1. Position thermostat flush with tank surface.
2. Check heating elements. Replace as needed.
3. Adjust thermostats to desired setting.
4. Check thermostats, replace as needed.
5. Check ECO, replace thermostat as needed.
6. Replace with larger heater.
Over Heated
Water or
Continues
Operation
4. Inoperative thermostats.
5. Inoperative ECO.
6. Undersized water heater.
7. Incorrectly adjusted mixing device.
7. Adjust mixing device.
8. Improperly programmed solar controller. 8. Refer to solar controller instructions.
7. Refer to included mixing
device instructions.
Noisy (singing or
hissing) Elements
1. Lime formation on elements.
1. Remove and clean heating elements.
Replace as needed.
1. See Service Procedure
RE-V, Page 13.
7
SERVICE PROCEDURE RE-I
Line Voltage & High Limit (ECO)
Testing
Line Voltage Testing
WARNING
High voltage exposure. Use caution when
making voltage checks to avoid personal injury.
1. Turn “OFF” power to water heater.
2. Remove access cover(s) from front of water
heater. Remove insulation and plastic cover
from thermostat.
ECO reset
button
3. Set multi-meter to volts AC.
4. Turn power “ON” to water heater.
5. Check voltage across terminals L1 & L3
of upper thermostat (see illustration 2).
A) Rated voltage IS present, power to the water
heater is okay.
B) Rated voltage NOT present, Check circuit breaker
at service panel.
Illustration 2
Illustration 3
High Limit (ECO) Testing
1. Check voltage across terminals L1 & L4 upper thermostat (see illustration 3).
A) Rated Voltage IS present, ECO is okay.
B) Rated voltage NOT present, proceed to step 2.
2. Turn power “OFF” to water heater and firmly press ECO reset button on thermostat. Turn power “ON” and recheck
voltage across terminals L1 & L4 of upper thermostat
(see illustration 3).
A) Rated voltage IS present, the ECO has previously opened indicating the water in the tank, at
some point did overheat, check the following:
1. Thermostat must be in full contact with tank.
2. Be sure heating elements are not shorted to ground (see page 9).
3. Proper thermostat operation (see procedures beginning on page 10).
B) Rated voltage NOT present, water in tank may be over heated.
1. If water is hot, turn “OFF” power to water heater and flow water through tank to cool below set point
of upper thermostat. Recheck voltage per step 1.
2. If water is cool, Replace upper thermostat.
8
SERVICE PROCEDURE RE-II
Heating Element Testing
Testing For Open Or Burned Out Element.
WARNING
High voltage exposure. Be sure power is turned
OFF to water heater prior to performing this
procedure.
Step 1. TURN OFF POWER TO WATER HEATER.
Step 2. Remove access covers from front of water
heater. Remove insulation and plastic cover
from thermostat.
Step 3. Disconnect wires from heating element.
Step 4. Set multi-meter to “ohms” setting.
Step 5. Touch probes of multi-meter to screw
terminals of heating element
(see illustration 4).
Meter Probe
Step 6. Reading should be 12.8 ohms ( 6%) for a 240
volt, 4500 watt element:
Ohms = Volts2
Watts
A reading outside the range using the formula
above ( 6%), indicates a bad element and the
element must be replaced.
Element Screw Terminals
Illustration 4
Testing For Heating Element Short Circuit To
Ground.
Step 1. TURN OFF POWER TO WATER HEATER.
Step 2. Remove access covers from front of water
heater. Remove insulation and plastic cover
from thermostat.
Step 3. Disconnect wires from heating element.
Step 4. Set multi-meter to “ohms” setting.
Element Screw Terminal
Meter Probe
Step 5. Touch one probe of multi-meter to either screw
terminal of heating element and the other on
the element flange (see illustration 5). There
should be no reading on the ohm meter. Any
reading indicates a grounded element and the
element must be replaced. Repeat this step for
the other screw terminal.
Element Flange
Illustration 5
9
SERVICE PROCEDURE RE-III
Thermostat Testing
WARNING
Double Element, Non-Simultaneous, Single Phase
Operation.
High voltage exposure. Use caution to avoid
personal injury during this procedure.
Water In Tank Is Cold With Power ON.
1. This procedure assumes line voltage, ECO and
elements are in working order.
2. Turn power “ON” to water heater.
3. Set multi-meter to “Volts AC”.
4. Check across terminals L4 and T2 of
upper thermostat (see illustration 6).
A) Rated voltage NOT present,
Recheck ECO. If ECO is okay,
replace thermostat.
B) Rated voltage IS present,
proceed to next step.
5. Check across element terminals
(see illustration 7).
A) Rated voltage NOT present,
check wire connections from
thermostat to element.
Illustration 6
Illustration 7
B) Rated voltage IS present,
Repeat element testing
see page 9.
Tank Does Not Deliver Enough Hot Water.
1. This procedure assumes line voltage, ECO and
elements are in working order.
2. Turn power “ON” to water heater and set multi-meter to “Volts AC”.
3. Adjust temperature setting of upper thermostat to the highest setting.
Water temperature in tank must be below thermostat setting for this test.
4. See illustration 6 above, check voltage across terminals L4 and T2 of upper
thermostat.
A) Rated voltage IS present, okay, upper thermostat is
calling for heat. Go to step 5 below.
B) Rated voltage NOT present, replace upper thermostat.
5. Adjust temperature setting of upper thermostat to the minimum setting.
Water temperature in tank must be above thermostat setting for this test.
6. Check voltage across terminals L4 and T4 of upper thermostat
(see illustration 8).
A) Rated voltage NOT present, replace upper thermostat.
Illustration 8
B) Rated voltage IS present, thermostat is okay. Go to step 7 on next page.
10
SERVICE PROCEDURE RE-III
Thermostat Testing
WARNING
Double Element, Non-Simultaneous, Single Phase
Operation (continued).
High voltage exposure. Use caution to avoid
personal injury during this procedure.
Not Enough Hot Water (continued).
7. Check voltage across terminal L4 of upper
thermostat and terminal 1 of lower thermostat
(see illustration 9).
A) Rated voltage NOT present,
- check wire connection between thermostats.
B) Rated voltage IS present, okay, go to step 8.
8. Adjust lower thermostat to highest setting. Water temperature in
tank must be below the lower thermostat setting for this test.
9. Check voltage across terminal L4 of upper
thermostat and terminal 2 of lower thermostat (see illustration 10).
A) Rated voltage NOT present, replace lower thermostat.
B) Rated voltage IS present, thermostat is ok.
WARNING
Be sure thermostats are reset to their original
temperature settings as found prior to
thermostat testing
Illustration 9
Water Temperature In Tank Is Above Thermostat Setting.
1. This procedure assumes line voltage, ECO and elements are in working
order.
2. Adjust upper and lower thermostats to the lowest setting.
3. Turn power “ON” to water heater and set multi-meter to “Volts AC”.
4. Check across terminals L4 and T2 of upper thermostat
(see illustration 6 on page 10).
A) Rated voltage IS present, replace upper thermostat.
B) Rated voltage NOT present, upper thermostat is okay. Go to step
5 below.
C) Lower than rated voltage IS present, recheck for grounded upper
element (see page 9).
5. Check across terminals L4 and 2 of lower thermostat (see illustration 10).
A) Rated voltage IS present, replace lower thermostat.
Illustration 10
B) Rated voltage NOT present, lower thermostat is okay.
C) Lower than rated voltage IS present, recheck for grounded lower
element (see page 9).
11
SERVICE PROCEDURE RE-IV
Thermostat Removal and Replacement
Thermostat Removal
WARNING
High voltage exposure. Be sure power is
“OFF” when performing this procedure.
1. Turn power “OFF” To water heater.
2. Remove access cover and insulation.
3. Remove plastic thermostat protector from thermostat.
4. Disconnect wires from thermostat terminals. It may be necessary to label wires for proper re-connection to
new thermostat.
5. Note thermostat temperature setting for proper setting of new thermostat.
6. Slide thermostat upwards and out of mounting bracket.
Thermostat Replacement
1. Use a stiff brush to remove any debris or loose scale from tank surface where new thermostat will be installed.
2. Slide new thermostat down into thermostat bracket until it snaps into place. IMPORTANT! Thermostat must set
completely flat or flush to tank surface. An improperly installed thermostat will cause improper water heater
operation.
3. Refer to the wire diagram located on the inside of the access cover and re-connect wires to the thermostat. Be
sure wire connections are snug and corrosion free. Do not over tighten, doing so may damage thermostat.
4. Set thermostat to the original thermostat setting found on the old thermostat.
5. Re-install plastic thermostat protector.
6. Re-install insulation and access cover.
7. Restore power to water heater and verify proper heater operation.
Tank Surface
Proper Thermostat mounting
flush with tank surface
Thermostat
Improper Thermostat mounting.
Thermostat not flush with tank surface
Thermostat
mounting
bracket
Front View
Thermostat Mounting
Side View
Improper Thermostat
Mounting
Side View
Proper Thermostat
Mounting
12
SERVICE PROCEDURE RE-V
Heating Element Removal
and Replacement
WARNING
High voltage exposure. Be sure power is
“OFF” when performing this procedure.
Heating Element Removal
1. Turn power “OFF” To water heater.
2. Turn off cold water supply to heater. Connect hose to drain
spigot of water heater and route to an open drain. Open
a nearby hot water faucet to vent heater for draining. Open
drain spigot of water heater and allow heater to drain
to a point below the elements.
WARNING
Heater components and stored water may be
HOT when performing the following steps in
this procedure. Take necessary precaution to
prevent personal injury.
3. Close drain spigot and remove hose.
4. Remove access cover and insulation.
5. Remove plastic thermostat protector from thermostat.
6. Disconnect wires from element terminals.
7. Remove element from tank using 1-½ deep well socket or appropriate wrench. Unscrew element counter-clockwise to
remove from tank.
8. Be sure to remove old element gasket from the tank. It is not recommended to be re-used.
Heating Element Replacement
1. Check element terminal block for proper electrical rating. NOTE: Some elements have dual ratings, be sure to check
all surfaces of the element terminal block (see illustration below).
2. Apply new element gasket to the new element. Be sure gasket is seated flat against element flange without rolls or
gaps (see illustration below).
3. Clean any debris from element fitting on tank. Lubricate element threads as needed with thread lubricant.
4. Thread new element clockwise into tank. Tighten element using 1-½ deep well socket or appropriate wrench. Do not
over tighten, over tightening may damage element gasket.
5. Reconnect wires to element, be sure wires are snug and corrosion free. Do not over tighten, doing so may damage
terminal block.
6. Resume water supply to heater, be sure tank is full of water and check for leaks.
7. Re-install plastic thermostat protector.
8. Re-install insulation and access cover.
9. To resume operation, BE SURE TANK IS FULL OF WATER and restore power to water heater. Verify proper heater
operation.
Element Rating.
Example: (4500 Watt, 240 Volt)
Date Code
Element Flange
Element Gasket Seated Flat Against
Element Flange Without Rolls or Gaps
Terminal
Block
Manufacturer Identification
13
SERVICE PROCEDURE RE-VI
Dip Tube and Anode Inspection and
Replacement
Dip Tube Inspection and Replacement
WARNING
Heater components and stored water may be HOT when performing the following steps in
this procedure. Take necessary precaution to prevent personal injury.
Step 1.
Turn power “OFF” to water heater.
Step 2.
Turn off cold water supply to heater. Connect hose to drain spigot of water heater and route to an open drain.
Open a nearby hot water faucet to vent heater for draining. Open drain spigot of water heater and allow
heater to drain to a point below the inlet connection nipple.
Step 3.
Step 4.
Step 5.
Close drain spigot and remove hose.
Disconnect inlet nipple from plumbing system.
With an appropriate wrench, remove inlet nipple/dip tube from the water heater. Use caution not to damage
nipple threads.
Step 6.
Visually inspect inlet nipple/dip tube. Inlet nipple/dip tube should be free of cracks and any blockage.
Hydro-jets located near the bottom of the dip tube should be open and free of any blockage.
Anti-siphon hole located approximately 6" from the bottom of nipple, should be free of any blockage.
Any damage such as cracks, restriction due to deformation or unintentional holes are not field repairable
and the inlet nipple/dip tube must be replaced.
Step 7.
Step 8.
Upon completion of inspection or subsequent replacement, reinstall inlet nipple/dip tube into heater. Connect
nipple to plumbing system, close spigot and remove drain hose, resume water supply and refill heater with
water.
To resume operation, BE SURE TANK IS FULL OF WATER and turn power “ON” to water heater.
Anode Inspection and Replacement
Step 1.
Step 2.
Turn power “OFF” to water heater.
Turn off cold water supply to heater. Connect hose to drain spigot of water heater and route to an open drain.
Open a nearby hot water faucet to vent heater for draining. Open drain spigot of water heater and allow
heater to drain to a point below the outlet connection nipple.
Step 3.
Step 4.
Step 5.
Close drain spigot and remove hose.
Disconnect outlet nipple from plumbing system.
With an appropriate wrench, remove outlet nipple/anode from the water heater. Use caution not to damage
nipple threads.
Step 6.
Step 7.
Step 8.
Visually inspect outlet nipple/anode. Outlet nipple/anode should show signs of depletion, this is normal.
If depletion is ½ of the original anode diameter (original diameter approximately ¾”), replacement is
recommended. If any of the steel core of the anode is exposed, replacement is recommended.
Upon completion of inspection or subsequent replacement, reinstall outlet nipple/anode into heater. Connect
nipple to plumbing system, close spigot and remove drain hose, resume water supply and refill heater with
water.
To resume operation, BE SURE HEATER IS FULL OF WATER and turn power “ON” to water heater.
14
Generic Parts List
1. Integrated Mixing Device
2. Hex Head Anode
3. Junction Box Cover
4. Cover Conduit/Ground
5. ¾" Plug
10. Heating Element
11. Thermostat Mounting Bracket
12. Thermostat w/High Limit (89T33)
13. Element Gasket
14. T&P Relief Valve
6. Hot Water Outlet/Anode
7. Cold Water Inlet Dip Tube
8. Access Cover
15. Lower Thermostat Protector (Small)
16. Thermostat (59T)
17. Brass Drain Valve
9. Thermostat Protector (Large)
18. Kit Dairy Barn Leg
15
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