SunEarth CASCADE 2 Installation, Operation And Maintenance Manual

SRCC OG--
SRCC OG
Installation, Operation and Maintenance Manual
Installation, Operation and Maintenance Manual
300 Certified Solar Water Heating System
300 Certified Solar Water Heating System
CASCADE 2
DOMESTIC SOLAR WATER
INSTALLATION, OPERATION AND MAINTENANCE MANUAL
The Cascade 2 domestic water heating system has gone through an extensive design, technical and per­formance review by the Solar Rating & Certification Corporation (SRCC). The installation of your Cascade 2 system is intended to be executed by properly licensed and experienced professional contractors in ac­cordance with SRCC Standard OG-300, “Operating Guidelines and Minimum Standards For Certifying”, and shall conform to applicable federal, state and local regulations, codes, ordinances and standards gov­erning the installation of solar water heating systems.
The solar energy system described by this manual, when properly installed and maintained, meets the minimum standards established by the SRCC. This certification does not imply endorsement or warranty of this product by the SRCC.
OG-300 system certification is granted to SunEarth by the SRCC. It may not be used for any commercial purpose without prior written consent of SunEarth. SunEarth must approve any deviation from the mate­rials and methods described in this manual in writing.
The Cascade 2 Drainback solar water heating systems can be protected against freeze damage to temperatures as low as -50ºF (-46ºC). This system should not be installed in areas within the continental United States where the annual ambient temperature has ever fallen below minus 50° Fahrenheit (-46° Celsius). The Cascade 2 Drainback system must be installed as specified in this manual to have effective freeze protection at these low temperatures.
Freeze tolerance limits are based upon an assumed set of environmental conditions. Extended periods of cold weather, including ambient air temperatures above the specified limit may cause freezing in exposed
parts of the system. It is the owner’s responsibility to protect the system in accordance with SunEarth’s
instructions if the ambient temperature approaches the specified freeze tolerance limit.
TABLE OF CONTENTS
1) Introduction ......................................................................... 1
2) System Description and Operation Principle ........................ 1
3) Installation RequirementsGeneral ..................................... 2
4) Installation RequirementsSpecific ..................................... 2
5) Start Up Procedures ........................................................... 13
6) Modes of System Operation ................................................ 13
7) System Shut Down and Isolation Procedures ..................... 14
8) Vacation procedures .......................................................... 14
9) Maintenance and Troubleshooting ...................................... 14
10)Cascade 2 System Component Parts ................................. 15
11)Estimated Component Life ................................................ 16
12)System Operating Parameters .......................................... 16
Appendix A. Approved Primary Components ........................... 18
Appendix C. System and Component Labels ........................... 22
Appendix F. SunEarth Collector Warranty Statement ............. 24
Appendix G. SRCC OG-300 Certified System Model Numbers . 26
Appendix H. Supplier and Service Contact Information ......... 27
IMPORTANT SAFETY INFORMATION
READ ALL INSTRUCTION BEFORE USING
DANGER!
!
WATER TEMPERATURE SETTING
Safety and energy conservation are factors to be considered when selecting a water temperature setting of the water heater’s thermostat. Water temperatures above 125°F can cause severe burns or death from scalding. Be sure to read and follow the warnings outlined on the label pictured below.
Time/Temperature Relaonship in Scalds
Temperature Time To Produce a Serious Burn
120°F More than 5 minutes 125°F 11/2 to 2 minutes 130°F About 30 seconds 135°F About 10 seconds 140°F Less than 5 seconds 145°F Less than 3 seconds 150°F 11/2 seconds 155°F About 1 second
Table courtesy of Shriners Burn Instute
The chart shown above may be used as a guide in determining the proper water temperature for your home.
!
DANGER! Burns from Hot Water and SteamUse
The electrical element booster thermostat has been factory set at 50°C (120°F) to reduce the risk of scald injury. Adjusting the thermostat to a higher setting is not recommended. Hotter wa­ter increases the potential for Hot Water Scalds.
!
DANGER!: Hoer water increase the potenal for hot Water SCALDS.
extreme care when opening relief valves, and filling storage tanks.
!
DANGER! Households with small children, disabled,
NOTICE: Mixing valves should be installed to reduce the point of use water temperature by mixing hot and col wa­ter in branch water lines. Contact a licensed installer or the local plumbing authority for further information.
The temperature of the water in the water heater can be regulat­ed by setting the temperature dial of the adjustable surface mounted thermostat located behind the jacket access panel.
or elderly persons may require a 120°F or lower thermostat setting to prevent con­tact with “HOT” water.
This thermostat controls the
water heater’s heating ele-
ment only. ( A separate thermostat should be uti­lized in monitoring the tem­perature from the collector).
To comply with safety regu­lations the thermostat is factory set at 120°F or less where local codes require.
IMPORTANT SAFETY INFORMATION
READ ALL INSTRUCTION BEFORE USING
WARNING!
!
For your safety, the information in this manual must be followed to minimize risk of fire or explosion, electric shock, or to prevent property damage, person­al injury, or loss of life.
Be sure to read and understand the entire installation, Operation and Mainte­nance manual before attempting to install or operate this water heating sys­tem. It may save you time and cost. Pay particular attention to the Safety in­structions. Failure to follow these warnings could result in serious bodily injury or death. Should you have problems understanding the instructions in this manual, or have any questions, STOP, and get help from a qualified service technician, or the local utility.
SAFETY PRECAUTIONS
!
Have the installer show you the location of the circuit breaker and how to shut it off if necessary. Turn off the circuit breaker if the water heater has been subjected to over­heating, fire, flood, or physical damage or if the ECO fails to shut off.
Read this manual entirely before in-
stalling or operating the water heating system.
Use this appliance only for its intended
purpose as described in this installa­tion, operations and Maintenance Man­ual.
Be Sure your appliance is properly
installed in accordance with local codes and the provided installation instruc­tions.
Do not aempt to repair or replace
any part of your water heang system unless it is specically recommended in this manual. All other servicing should be referred to your installing contractor or local SunEarth distribu­tor.
READ AND FOLLOW THIS SAFETY INFORMATION
SAVE THESE INSTRUCTIONS
CAREFULLY.
PREFACE
Let us first offer two words of grateful appreciation. Thank You!. We sincerely appreciate your business.
SunEarth also wishes to say thank you for “going so­lar”. Solar water heating systems help to reduce our nation’s dependence on polluting fossil fuels, minimize
the greenhouse gas emissions associated with conven­tional water heating and, very importantly, lower you monthly utility costs.
Established in 1978, SunEarth is a leading U.S. solar equipment manufacturer. Our products include the in­dustry standard Empire, Imperial, ThermoRay and Sun­belt solar water heating collectors as well as the Cop­perHeart integral collector storage system and SunSi­phon packaged Thermosiphon systems, SunBurst all copper absorber plates, Solar Strut and RexRack mounting hardware. We also fabricate specialty collec­tors for unique architectural and building applications. SunEarth SRCC OG-300 certified solar water heating systems are sold by leading solar plumbing and build­ing contractors throughout the United States.
Your Cascade 2 solar water heating system has been designed to meet exacting SRCC OG-300 certification requirements. The components found in your system have been selected by your installation contractor for their proven reliability, longevity and performance in your specific region of the country.
SunEarth Inc. maintains a policy of continuous review and improvement to ensure that Cascade 2 systems incorporate any appropriate technological advances. To ensure that products represent the current state of the art in solar water heating Cascade 2 systems are sub­ject to change without notice. Please consult the SunEarth website at www.sunearthinc.com for current information and the latest manual revisions.
1) INTRODUCTION
Solar water heating systems are climate and site spe­cific appliances. Different types of solar systems are installed around the world in accordance with regional weather and water quality conditions. System perfor­mance varies as a function of the household hot water load, average ground water, ambient air temperature,
the home’s roof pitch and orientation and of course the
seasonal intensity of solar radiation. These variables, some of which change from home to home on the same neighborhood street will determine how much energy and money your Cascade 2 system will save on an an­nual basis.
Your Cascade 2 Drainback solar system is known as a
“forced circulation closed loop drainback” system be-
cause it utilizes a mechanical pump to efficiently circu­late water throughout the unpressurized closed loop
solar piping. The “drainback” connotation refers to the
freeze-protection mechanism used in the system. In drainback systems, the heat exchange fluid (water) in the collector array and solar loop piping drains back by
gravity into the drainback storage reservoir when the pump stops circulating. Air replaces water in the col­lector array and solar loop piping to prevent it from freezing when the pump is off.
This manual is intended as a basic solar water heating primer. Our goal is to familiarize you with the proper installation, operation and maintenance of your Cas­cade 2 solar water heating system. This system is re­quired to be installed by properly licensed solar or plumbing contractors in accordance with SRCC OG-300 and all applicable national, state and local codes, ordi­nances and regulations governing solar water heating installations, as well as good trade practices. Failure to follow the procedures and practices described in this
manual may void the manufacturer’s warranty and spe-
cific component parts.
This manual covers installations utilizing one or two SunEarth solar collectors with a single solar storage tank and also two tank systems that include a solar storage tank and supplemental tank type or tankless water heater. Frequent reference is made throughout this manual to specific component parts. The place­ment of each component can be seen in the system schematic Figures 3 & 4. A description of each compo­nent and its function is found in Section 10.
2) SYSTEM DESCRIPTION AND OPERATIONAL PRINCIPLE
The key components in the Cascade 2 solar water heat­ing system include the SunEarth solar collector, solar storage tank, circulation pump and differential temper­ature controller.
The SunEarth solar collector is the heart of the Cascade 2 system. Simply stated, when the sun is shining, heat
energy is absorbed by the solar collector’s absorber
plate and transferred to the potable water circulating between the solar collector and storage tank. This pro­cess is continuously repeated during the average sunny day as the temperature in the solar storage tank rises.
The differential temperature controller is the brain of the system. The controller uses temperature sensors to consistently monitor the temperatures at the collector and at the tank. the controller automatically turns the pump on when useful heat is available at the collector and turns the pump off when there is insufficient solar heat available or the tank had reached maximum tem­perature. Cascade 2 systems are designed to provide two modes of operation. The system will, (1) serve as a preheater to your solar storage tank, or (2) bypass the solar collector and run 100% on utility or conventional fuel. The installation of an optional water heater time switch allows you to control both the frequency and duration of supplemental electric resistance water heating. Supplemental electric heat may not be re­quired for much of the year depending upon your spe­cific requirements, thus providing an effective third mode of operation100% solar.
Section 6 provides instructions for setting the system for automatic operation in each of these two modes.
The water in the SunEarth collector and the solar loop piping automatically drains back into the drainback res­ervoir each time the circulating pump turns off. Gravi­ty drains the piping and provides the freeze protection for your Torrent Drainback system.
To ensure proper drainage the SunEarth solar col­lector must be installed in the vertical position so that the internal riser tubes are run parallel, not perpendicular, to the slope of the roof.
The system also can be manually drained in order to
protect the integrity of the collector and solar loop pip-
ing if it is exposed to extended periods of disuse or
persistent hard freeze conditions below - 50° Fahren-
heit. (See Section 7 for instructions).
3) INSTALLATION REQUIREMENTSGENERAL
3.1 Permits:
3.6 Building Envelope:
Penetrations though the building envelope (including roof, walls or floor penetrations) must not impair the enclosure function and must meet applicable codes and best practices.
Roof penetrations whether for structural mounts or pipe penetrations must be sealed and leak proofed as per applicable codes and national Roofing Contractor Association practices.
Building penetrations must not allow vermin intrusion.
3.7 Fire-Rated assemblies:
Penetrations through fire-rated components must not reduce the fire resistance of the assembly below code requirements.
3.8 Building Materials:
Building materials adjacent to solar components must not be exposed to elevated temperatures.
The contractor shall obtain all required permits and ap­provals.
3.2 Codes, Ordinances and Standards:
The installation shall conform to all federal, state and local regulations, codes, ordinances and standards gov­erning the installation of solar water heating systems. The contractor shall adhere to sound building safety and trade practices. Special consideration must be giv­en to building code requirements for roof loading and the penetration of structural members as well as fire rated assemblies.
3.3 Shading Considerations:
The collectors must be located in an area of the roof or otherwise that will not be shaded for the majority of the day all year round. Adjacent buildings and tress should be checked for possible shading. The collector should not be shaded by any permanent obstacle be­tween 9:00 a.m. and 3:00 p.m. on any day of the year. A shading instrument such as the Solar Pathfinder can be used for solar site analysis.
3.4 Roof and Site inspection:
Before the installation, the contractor shall inspect the condition of the roof and notify the homeowner of any existing roof damage or necessary repairs.
3.9 Confirmation of Installation Site:
The homeowner and contractor shall confirm the loca­tion of all roof and other mounted components in ad­vance of the installation.
3.10 Fluid Identity and Toxicity
The Cascade 2 Drainback system uses water as a heat transfer fluid, this is heated in the collector and indi­rectly heats the domestic hot water through the exter­nal heat exchanger. Use of toxic heat transfer fluids is prohibited.
3.11 Maintenance and Servicing
When installing the system, make sure that all the components are accessible and easy to reach. Provide for clear access to the storage tank, pump, mixing valve and other key components. If a component in the potable water side of the system may require future maintenance or service make connections with brass unions or other approved methods.
4) INSTALLATION REQUIREMENTSSPECIFIC
COLLECTOR ORIENTATION
3.5 Structural Considerations:
The collectors must be located in a structurally sounds area of the roof. Penetrations into structural members must not compromise the structural properties of the member.
ENSURE THAT ALL STRUCTURAL MEMBER PENE-
TRATIONS COMPLY WITH APPLICABLE CODES.
The collector mounting method must be capable of maintaining the required tilt and azimuth of the collec­tor under the expected dead loads, winds loads, snow loads and seismic loads for the location.
S
4.1 Collector Orientation
Fig.1
T1
2
PIPE INSULATION
SINGLE TANK SYSTEM
SCHEMATIC
1
COLD SUPPLY LINE
HOT SUPPLY
LINE TO FIXTURES
(1) SunEarth Solar Collector(s)
(2, 3, 4) Temperature Sensor
(5, 6, 7, 8, 22) Ball Valve
(11, 24, 35, 36) Combinaon Valve
(9) Pressure Relief Valve
(10) Drain Back Tank
(12, 13) Pump
(14) Heat Exchanger
(17) Dierenal Temperature Controller
(18) Heang Element & Tank Thermostat
(19, 20) Temperature and Pressure Relief Valve
(21) Mixing Valve (23) Water Heater (25) Solar Tank
4
T3
20
8
9
ROOF JACKS
35
10
17
22
48” min.
12
24
25
T2
3
36
14
13
11
Fig.2
TWO TANK
SYSTEM
SCHEMATIC
T1
2
1
PIPE
(1) SunEarth Solar Collec-
tor(s)
(2, 3, 4) Temperature Sensor
(5, 6, 7, 8, 22) Ball Valve
(11, 24, 35, 36) Combina­on Valve
(9) Pressure Relief Valve
(10) Drain Back Tank
(12, 13) Pump
COLD SUPPLY LINE
HOT SUPPLY LINE TO FIXTURES
8
(14) Heat Exchanger
(17) Dierenal Temper-
ature Controller
(18) Heang Element & Tank Thermostat
(19, 20) Temperature and Pressure Relief Valve
(21) Mixing Valve (23) Water Heater (25) Solar Tank
5
INSULATION
21
6
20
T3
4
7
9
ROOF JACKS
35
10
17
23
18
19
25
3
T2
36
24
14
13
22
12
48” min.
11
Fig.3
TANKLESS
SYSTEM
SCHEMATIC
2
T1
1
(1) SunEarth Solar Col-
lector(s)
(2, 3, 4) Temperature Sensor
(5, 6, 7, 8, 22) Ball Valve
(11, 24, 35, 36) Combina­on Valve
(9) Pressure Relief Valve
(10) Drain Back Tank
(12, 13) Pump
COLD SUPPLY LINE
HOT SUPPLY LINE TO FIXTURES
(14) Heat Exchanger
(17) Dierenal Temper-
ature Controller
(18) Heang Element & Tank Thermostat
(19, 20) Temperature and Pressure Relief Valve
(21) Mixing Valve (23) Water Heater (25) Solar Tank
8
5
PIPE INSULATION
21
6
20
T3
4
7
9
ROOF JACKS
35
10
17
19
23
25
T2
3
36
24
14
13
22
12
48” min.
11
Fig.4
The performance of solar water heating systems in the Northern Hemisphere is optimized when the collector is mounted facing True South. Performance, however, suffers very little when the collector is oriented no more than 45° East or West of True South. The collec­tor should not be shaded by any permanent obstacle between 9:00 a.m. and 3:00 p.m. on any day of the year.
4.2 Collector Tilt
highest point in the system back to the drainback reservoir.
The minimum required slope is 1/4” vertical drop per
foot of horizontal piping run (2% minimum slope). Use the steepest slope possible on the return line piping to the drainback reservoir. Water will drain down both the return tubes directly to the drainback reservoir and the supply tubes by spinning the pump impeller in the re­verse direction.
Optimal annual efficiency is achieved by tilting the so­lar collector at and angle that equals your latitude plus an additional 10°. This tilt angle favors the lower winter sun when the collector performance is at its lowest and minimizes overheating during the hottest summer months.
To ensure proper water drainage from the glazing the collector must be sloped from horizontal. Never mount the collector parallel to a flat roof. Use SunEarth RexRack, Landscape Rack or Universal Tilt Kit products to raise the collector to a proper angle. The minimum acceptable tilt angle from horizontal is 15°.
The solar collectors in a two collector staggered mount installation must be spaced far enough apart to prevent winter shading when the sun is at its lowest angle on the winter solstice.
4.3 Basic Mounting Procedures
The SunEarth solar collector in your Cascade 2 Drain­back solar system must be mounted in a vertical orien­tation parallel to the slope of the roof. See Figure 1. This orientation allows the internal riser tubes to rapid­ly drain when the circulation pump shuts off.
The collector should be mounted as close to the stor­age tank as possible to minimize heat loss in the piping runs. If the home has attic access, mounting the collec­tors near the roof peak provides for additional attic workspace.
The solar collector should be mounted on the roof in accordance with these general principles:
4.3.1 The most important structural considerations is to securely anchor the solar collector and the SunEarth mounting hardware to the structural members of the roof with stainless steel hanger bolts, lag bolts, stand­off mounts or other approved roof attachment meth­ods. The solar collector shall be attached to the mount­ing hardware as detailed in Figures (6-9). (Note: The drawings in the manual detail mounting hardware for the SunEarth Empire, Imperial, SunBelt and Ther-
STRUT ON FOOT MOUNT FOR
COMPOSITION ROOF
REXRACK
C-SSN
SUPPORT STRUT
FRONT MOUNTING FOOT
REAR TELESCOPING LEG
Fig.5
CRITICAL: Both the collectors and the solar loop piping must be sloped to drain away from the
COLLECTOR
C-SSN
FOOT MOUNT
STAINLESS LAG BOLT
FLASHING
Fig.6
moRay series collectors.)
4.3.2 The collector should be raised from the roof sur­face to allow for rainwater and debris to pass under the collectors and for proper ventilation of the roofing ma­terial. There should be at least 11/2” of clearance be­tween the roof surface and the bottom of the solar col­lectors. Local codes may require greater clearance and shall be followed accordingly.
4.3.3 When selecting mounting hardware and fasten­ers it is extremely important to avoid galvanic corro­sion resulting from the direct contact of incompatible
STRUT ON STANDOFF FOR FLAT
STRUT ON STANDOFF FOR
TILE ROOF
COLLECTOR
C-SSN
STANDOFF
LEAD FLASHING
STAINLESS LAG BOLT
Fig.7
STRUT ON STANDOFF FOR
COMPOSITION ROOF
CURVED TILE ROOF
COLLECTOR
C-SSN
STANDOFF
LEAD FLASHING
BASEFLASHING
STAINLESS LAG BOLT
mounting procedures. Consult you local building de­partment regarding any special considerations for your area.
4.4 Collector Loop Plumbing
Fig.9
COLLECTOR
C-SSN
STANDOFF
LEAD FLASHING
STAINLESS LAG BOLT
Fig.8
metals. Use of SunEarth anodized aluminum Solar Strut mounting hardware and stainless steel lag or hanger bolts, fastening hardware is recommended. In climates subject to severe winters or high humidity use of galvanized fasteners is prohibited.
4.3.4 Preserving the integrity of the roof membrane is the most important roofing consideration. Ensure that all roof penetrations required to plumb
and mount the solar collectors are properly flashed and sealed in accordance with standard roofing practices and in compliance with all local codes and ordinances.
4.3.5 If the region is subject to hurricane conditions, additional steps may be required to secure the collector and mounting hardware to the structural members. In certain areas of the country, local building codes may require collector wind load testing or prescribe specific
The collector loop must be plumbed using copper or stainless steel piping and copper, brass, bronze or stainless steel fittings. Lead-free solder shall be used. Use of galvanized steel, CPVC or PVC is prohibited. PEX may be used only in systems that meet the follow­ing conditions:
The PEX tubing shall not be exposed to sunlight.
Water must be used as the heat transfer fluid.
The system shall be non-pressurized (capped at at-
mospheric on the day of installation) or shall be vented to atmosphere.
A length of uninsulated copper tube no less than ¾”
nominal diameter shall be used at the hot outlet and cold inlet of the solar collector(s) for a distance
of no less than three feet (3’) before the transition
is made to PEX tubing.
All connections in the PEX piping runs shall be ap-
proved by the PEX manufacturer for potable water piping.
The system shall have a pressure-only relief valve
installed at the drainback tank location or shall be vented to the atmosphere. The pressure rating for the relief valve shall be no less than 25 psi and no more than 50 psi.
The collector loop pipe sizing must be adequately sized to handle the design flow rates for the collector(s).
SunEarth recommends ¾” nominal diameter pipe sizes for two collector systems and ½” nominal diameter
pipe sizes for one collector systems, except for the re­turn piping from the collector to the drainback tank, this should always be ¾” or larger.
CAUTION: The solar loop piping from the collector(s) to the drainback tank must be no less than 3/4” T-M cop­per tube to allow air to migrate up the tube ensuring full draining of the collector(s) and tubes.
It may be necessary to increase the pipe size for longer pipe runs or reduce the pipe size for shorter runs or higher efficiency pumps. The pipe must be large enough that the velocity of the water in the pipe does not exceed 4 ft/s. Hot water flowing at over 4 ft/s in a pipe will erode the pipe and reduce system life.
When more than one collector is used in the system, the collectors should be plumbed in a reverse return piping arrangement in order to maintain equal flows through all collectors in the array during normal opera­tion.
To ensure proper drainage of the collector array and solar loop piping the lines must be adequately sloped to drain back to the drainback reservoir.
CRITICAL: The required slope is 1/4” vertical drop per foot of horizontal run (2% slope). Failure to properly
COLLECTOR PLUMBINGSLOPED
TO DRAIN
1” x 3/4” CC 90° ELBOW OR COUPLING
1” CC COUPLING
RETURN LINE
1” CC CAP
SUPPLY LINE
COLLECTOR PLUMBING
CORRECT INCORRECT
WILL TRAP FLUID
Fig.11
lined below.
All vertical piping between the storage tank and the collector shall be supported at each story or at maxi-
mum intervals of ten feet (10’). Horizontal runs shall
be sloped to drain (minimum 2% slope) and supported
every five feet (5’) to prevent sagging. Roof runs shall
be secured and supported providing at least 1-1/2 inches clearance from roof. Pipe supports shall be con­structed from a material that will not rot, compress or degrade over time as this may lead to pipe sagging and failure to drain. Standard best piping practices shall be followed as described in the Uniform Plumbing Code, International Plumbing Code or other recognized code or standard. Copper plumbers tape or tube strap is required. The pipe insulation should not be com­pressed or crimped by the strapping material.
1” CC COUPLING
1” CC CAP
1” x 3/4” CC 90° ELBOW OR COUPLING
Fig.10
orient the collector and solar loop piping to allow ade­quate drainage may result in freeze damage. SunEarth solar collectors are not warranted against freeze dam­age.
Figure 11 illustrates correct and incorrect methods of plumbing the solar collector array. Note that water will
trap in the “U” section of piping as illustrated in the
drawing marked incorrect thus making it susceptible to freeze damage.
Piping in new solar installations can be covered with dirt, grease, solder flux or other impurities that may affect the system performance. A thorough cleaning is required before charging. A Water soluble flux should be used when soldering pipe joints in the collector loop in order to facilitate system flushing. Carefully review
the cleaning procedures in “Charging the System” out-
Allowance should be made for expansion and contrac­tion of piping due to changes in temperature of the wa­ter and piping. Use flexible pipe supports and avoid long straight piping runs. Include bends and elbows to allow for expansion such as swing joints at the collector inlet & outlet.
The installation of all horizontal and vertical piping may not reduce the performance or rating of any structural member or fire rated assembly. Adhere to all applicable local codes and ordinances.
4.5 Pipe Insulation
WARNING: HOT PIPES MAY CAUSE BURNS IF TOUCHED. ENSURE THAT ALL PIPES AND FIT­TINGS ACCESSIBLE TO THE PUBLIC ARE WELL IN­SULATED. COMPONENTS ACCESSIBLE TO PUBLIC TRAFFIC MUST BE KEPT BELOW 140°F OR CLEAR­LY LABELLED WITH AN APPROPRIATE WARNING.
The collector loop piping, plus any interconnecting hot water piping shall be well insulated with high quality flexible closed cell insulation to minimize heat loss. The
COLLECTOR SENSOR
SENSOR CLAMPED TO HEADER PIPE & COVERED WITH INSULATION
SILICON SENSOR LEAD MAY BE IN CONTACT WITH PIPE
CRIMP OR SOLDER CONNECTION
The differential controller must have a provision to manually turn the pump on and off (manual override) so that the pump operation can be checked at any time and the pump can be manually stopped if required for maintenance or troubleshooting purposes.
Set the maximum tank temperature to the desired maximum temperature, this temperature must be low­er than the rated maximum temperature of the tank an associated components. When the solar loop heats the tank to the temperature, the pump will shut off
SENSOR WIRE MUST
NOT BE PLACE IN
DIRECT CONTACT WITH PIPE
PROTECTIVE INSULATION JACKET OR APPROVED COATING
RETURN LINE
Fig.12
insulation shall have a maximum operating tempera­ture of 220°F or higher. The wall thickness of the pipe insulation should be not less than 1/2”. A 1” wall thick­ness is required for exposed piping in all areas prone to annual hard freeze conditions. When it comes to pipe insulation the rule is simple: thicker is better.
To the extent possible, slide the insulation material over the pipe without cutting or taping. All butt joints must be sealed with contact adhesive. The use of rigid polyethylene pipe insulation is prohibited. The temper­atures generated by your collector in the summer months or under stagnation conditions can melt this type of material.
Any above ground exterior pipe insulation is subject to UV degradation and must be jacketed, wrapped with aluminum foil tape, or painted with two coats of high quality water-based acrylic resin coating as supplied by the insulation manufacturer.
4.6 Control System
4.6.1 Differential Controller
The differential controller must be installed in an acces­sible location so that the user interface, typically an LCD screen, can be seen. Switches on the controller must be labeled and accessible. Always follow the con­troller manufacturers wiring instructions when installing differential controllers. Control system inputs; such as signals from the temperature sensors or flow meters shall be connected to the appropriate low voltage ter­minals. Controller output to the pumps will be medium voltage, 110 VAC or 220 VAC. Medium voltage power to the pump may be supplied by a line cord from the pump to an outlet in the controller or hard wired from the controller medium voltage terminals to the pump. Wiring must comply with standard electrical practice and all applicable electrical codes for the jurisdiction having authority, this may require the use of conduit for medium voltage wiring.
preventing further heat gains to the solar tank.
4.6.2 Collector Sensor Placement
The collector sensor shall be located on the solar loop return line as close to the collector as possible. Sensors are typically accurate to ±1/2°F if properly installed and weatherized. The collector probe sensor shall be at­tached to the SunEarth collector header pipe either with a stainless steel hose clamp or by inserting the probe sensor into a thermal well in contact with the fluid near the outlet header pipe.
It is recommended that the connection between the silicon sensor lead and low voltage sensor wiring be made inside the attic, a NEMA 4X junction box or some other indoor space. When using wire nuts to make the connection, the crimped brass cap on the end of the sensor should be removed and the wire stripped before inserting into the wire nut for connection. Where con­nections from the sensor lead to the low voltage wiring is made at an exposed location the connection should be crimped and insulated with heat shrink or soldered and insulated with heat shrink. Wire nuts or screw con­nectors should not be used in exposed locations due to the likelihood of corrosion which will result in a com­promised electrical connection. Thoroughly wrap and
weatherize the insulation with electrician’s tape or insu-
lation tape as provided by the manufacturer. See Fig­ure 12 for collector sensor installation detail.
If an electrical potential exists between the roof and ground, this may induce current in the collector sensor wire. This current will result in a false signal being re­ceived by the controller and hence incorrect tempera­ture measurements. To prevent this current the collec­tors absorber plate and piping should be independently earth grounded. This will provide a separate path to ground from the roof which does not interfere with the sensor readings.
Grounding can be achieved by running a separate ground wire to the collectors or ensuring that the pipe in the solar loop is grounded and that there are no electrical discontinuities between the grounding point and the collectors absorber. Grounding of the collector & roof piping is especially important in locations that often experience electrical storms and electrical atmos­pheric activity.
4.6.3 Low Voltage Wiring
The low voltage wiring used in to connect the sensor lead to the controller shall be a minimum 18 AWG. The
wiring should be bare or tinned copper, two conductor, stranded, PVC insulated, with a PVC UV rated jacket suitable for exterior use. In locations that often experi­ence electrical storms and electrical atmospheric activi­ty the low voltage sensor wire should also be shielded with the shielding grounded.
Low voltage wire shall be rated for the full ranges of temperatures expected in the location, typically wire is rated up to 160°F. The low voltage sensor wire must not be in direct contact with the pipes as the wire insu­lation may melt when in contact with a hot pipe. Low voltage sensor wire must be run OUTSIDE the pipe in­sulation. Where the low voltage wire is run in an ex­posed location, it should be run OUTSIDE the pipe insu­lation but UNDER the insulation jacket or wrap to pro­tect the wire from UV exposure.
4.7 Installing the Solar tank
The solar tank is heated indirectly through the external heat exchanger by separate pumps on the collector loop and the potable side of the heat exchanger.
When plumbing the SunEarth solar storage tank and drainback reservoir make sure that all the components are accessible and easy to reach. Ensure that there is clear access to the storage tank, circulating pump, drainback reservoir, mixing valve, flow meter and other key components. If a component in the potable water side of the system may require future service or maintenance make the connections with brass unions. Use only brass nipples and unions and copper and brass fittings in plumbing the solar storage tank and drainback reservoir. The use of galvanized fittings or nipples, CPVC or PVC piping is prohibited.
Check valves are NOT ALLOWED anywhere in the col­lector loop. A check valve in the collector loop will pre­vent proper draining of the collectors and may result in freeze damage. If the pump used has an integral check valve, the check valve must be removed before
TANK SENSOR
THERMOWELL
JIFFY CLIP (ALTERNATIVE)
installing the pump in the system.
Hard copper connections to the city cold water supply line and the home hot water feed lines are recom­mended. The gaskets in standard water heater flex hose connectors can become brittle and compressed over time and begin leaking on the water heater. If not detected in a timely manner even a small drip or
leak may cause serious damage to the tank’s electrical
components or, in extreme cases, may cause the tank to leak from the outside in.
Tank plumbing is required to provide for the isolation of the solar storage tank from the city cold water supply line by means of an isolating ball valve.
The differential temperature controller shall have a screen readout to show temperatures of the collector and storage tank. Otherwise, line thermometers shall be installed in the collector supply and return lines to allow for a simple diagnostic check of proper system operation. On a sunny day the hot water return line should be approximately 5 – 15°F warmer than the wa­ter in the collector supply line.
The specified SunEarth controller continuously displays the temperature of the SunEarth collectors (T1) and the temperature at the bottom of the solar tank (T2). In addition, you may choose to install a third tempera­ture sensor (T3); this is normally installed at the hot water outlet on both single and double tank systems.
The Torrent Drainback system typically requires a high head, low flow circulating pump. The maximum head on the pump curve must be greater than the static lift head required to fill the system. The static lift head is the vertical height from the bottom of the drainback tank to the highest point in the system (usually the col­lector outlet header). When the pump is filling the sys­tem it will be pumping against the static lift head and should provide no less than 0.5 GPM flow. Once the system has been filled to the top of the collector, water will start to cascade down the return line filling the re­turn line as far as the drainback reservoir. Once this pipe is fully flooded the return line will start to siphon, resulting in an increase in flow as the system transi­tions from the filling condition to the running condition. In the running condition the flow rate should not ex­ceed 5 GPM. Good pump selection requires that the pump provide enough lift for the filling condition with­out excessive flow in the running condition. This is
usually achieved using a pump with a “steep” pump
curve. For multistory buildings, this can be especially challenging unless the drainback tank is located on the upper floor.
Fig.13
When there is a risk of pump cavitation due to high flow rates, a pump throttling valve (COMPONENT #22) may be located on the discharge, or upstream, side of the pump to adjust the solar loop flow rate and to pre­vent cavitation of the circulating pump. Cavitation is a fluid condition that can lead to pitting or other damage to the pump impeller. A throttling valve on the return piping from the collector to the drainback tank can also
be beneficial in situations where excessive noise is ex­perienced due to high flow rates into the drainback tank.
A brass boiler drain (COMPONENT #11) must be in­stalled at the lowest point in the system to allow for charging the solar loop piping and to serve as a drain valve for manual draining and maintenance.
A high quality thermostatic mixing valve is a required component in all OG-300 certified systems and should be plumbed in line with brass union connections for ease of future repair or replacement. The mixing valve shall be standard ASSE 1017 approved. The specified mixing valve should have an operating range between 95°F and 120°F. The mixing valve shall include a set point of 120°F delivered water temperature.
WARNING: SCALDING CAN OCCUR WITHIN FIVE SEC­ONDS WHEN WATER TEMPERATURES APPROACH 140° F. DESPITE THE INSTALLATION OF A MIXING VALVE IN YOUR TORRENT DRAINBACK SYSTEM, ALWAYS EX­ERCISE CAUTION WHEN OPENING A HOT WATER FIX­TURE OR FAUCET IN YOUR HOME.
The 3/4” cold water supply line to the solar storage
tank shall be insulated with R-2.6 or greater pipe insu-
lation to a minimum distance of 5’ behind the storage tank, or to the wall if closer than 5’.
less steel drainback tanks are available in 10; 15 and 20 gallons. Small glass lined steel electric water heat­ers available in various sizes from 6 to 20 gallons can also be used as drainback tanks; do not connect the heating element when using these tanks as a drainback reservoir. The minimum drainback tank volume must be DOUBLE the volume of the piping and collector loop above the initial fill level of the system. This volume is calculated from the fluid capacity of all the collectors in the system plus all piping above the drainback tank fill level.
TABLE 1
ARRAY DB-5 DB-7.5 DB-10
1 EP/EC-40 82 138 194
2 EP/EC-21 76 132 188
2 EP/EC-24 73 129 185
2-EP/EC-32 62 118 174
PIPE RUN LENGTHS FOR 1/2” TYPE M AND 3/4” TYPE M
RETURN LINES.
TABLE 2
ARRAY DB-5 DB-7.5 DB-10
Figures 11, 12 and 13 show the plumbing schematics for single and two tank Torrent Drainback systems. A brief explanation of the main components and their function is found in Section 10 below.
4.8 Tank Sensor Placement
Figure 13 details the proper placement of the solar storage tank sensor. The tank sensor shall have good thermal contact with the tank wall in order to accurate­ly measure the temperature of the water at the bottom of the tank. It is recommended that the sensor be in­stalled in a brass or copper thermal well screwed into the lower sensor port in the tank.
Thoroughly weatherize the wire connections in accord­ance with section 4.6.2.
4.9 Tank Insulation
Conventional back-up electric water heaters have insu­lation values between R-12 and R-20. the R value ex­presses the thermal resistance of the tank insulation. The higher the “R-value” the more effective the insula- tion is at preventing heat loss. The use of any solar storage tank with an R value belowR-12 is prohibited.
The storage tank should not be placed directly on an un-insulated floor or concrete slab, in order to prevent moisture damage to the base of the tank and reduce the heat loss to the floor. The tank should be raised off the floor on a pad.
4.10 Choosing and Installing the Drainback Res­ervoir
SunEarth CopperStorTM copper drainback tanks are available in 2.5; 5; 7.5 and 10 gallon capacities. Stain-
1 EP/EC-40 61 103 144
2 EP/EC-21 57 98 140
2 EP/EC-24 54 96 138
2-EP/EC-32 46 88 130
PIPE RUN LENGTHS FOR 3/4” TYPE M AND 3/4” TYPE M
RETURN LINES.
Select the appropriate tank based on the collector(s) chosen and the total length of solar supply and return loop piping in the system. Table 1 and Table 2 indi­cate the proper drainback tank for the two most com­mon piping scenarios. Our preference is to use Table 1:
1/2” piping for the supply line and 3/4” piping for the
return line. This provides some flow related benefits, extends the allowable pipe run and is slightly less ex­pensive.
The drainback reservoir shall be mounted in a location that is NEVER subjected to freezing conditions. The drainback tank may be mounted to a wall using brack­ets or on a stand over the solar tank. The outlet of the
drainback tank should be at least 48” above the suction
side of the circulating pump to give sufficient net posi­tive suction head available to the pump (See Figures 11, 12 and 13).
The drainback reservoir should be installed at the high­est location practicable. The benefits of this include: reduced risk of pump cavitation; reduced pumping head required to fill the system allowing smaller pumps to be used; and reduced piping above the drainback reservoir allowing smaller drainback tanks. In build­ings with two or more floors, it is beneficial to install
the drainback on the uppermost floor, preferably near the ceiling.
Drainback tanks are factory insulated to provide both heat retention and a noise buffer against the sound of falling water.
TABLE 3Specifications for SunEarth CopperStor
Drainback Reservoirs
SUNEARTH
MODEL
NUMBER
DB-5 12 50 5 42 5.0
DB-7.5 18 50 5 56 7.5
DB-10 24 50 5 84 10.0
MAXIMUM PRESSURE 160 PSIG, CONNECTIONS 3/4”
WIDTH
(IN)
LENGTH
(IN)
DEPTH
(IN)
DRY
WEIGHT
(LBS)
FLUID
CAPACITY
(GAL)
If your Torrent Drainback system includes the optional flow meter it should be plumbed so that the top of the flow meter is level with the top of the drainback tank so that the flow meter also provides a visual check of the fluid level in the system. The top and bottom of the flow meter should be supported to relieve stresses on the connecting unions.
DO NOT install the pressure relief valve (COMPONENT #9) on the drainback tank at this time. The COMPO­NENT #9 is threaded in place after the solar loop piping has been filled with water. See Section 4.13 for in­structions on charging the system.
4.12 Electrical and Wiring Requirements
When the electric element is used as the auxiliary heat source a properly licensed contractor shall make the 230 VAC electrical connection to the water heater or storage tank. If your solar contractor is not allowed by law to make these connections consult a licensed elec­trician.
Never activate the circuit breaker controlling the elec­trical heating element until the solar storage tank is
completely filled with water. This will prevent “dry fir­ing” and destruction of the heating element.
SunEarth recommends the use of a 115 VAC differen­tial control with a factory installed six foot line cord. The installation requires one 115 VAC outlet to be lo­cated neat the solar storage tank. The circulation pump line cord is then plugged into the receptacle on the controller. A 230 VAC control and circulation pump may be substituted where appropriate.
4.13 Heat Transfer Fluid (HTF)
The HTF must be a non-toxic fluid that meets FDA Gen­erally Recognized as safe (GRAS) Classification. The Torrent Drainback System uses water to meet this re­quirement.
Water used to fill the collector loop must meet certain minimum standards for purity. Impurities in the dilu-
tion water can increase metal corrosion, and cause the formation of scale and other deposits on the heat ex-
changer’s internal heat transfer surfaces. Distilled or
deionized water is recommended.
4.14 Flushing and Filling the System
Once the components have been plumbed it is time to fill the solar storage and collector loop with water as follows:
4.14.1 STEP 1 – Flush and Fill the potable loop with water.
Cl ose pot able fl ushing combination val ves (COMPONENTS #24 & 36). Fill the solar tank with wa­ter and check that there are no leaks on the potable side of the system.
Do this by opening the cold water isolation ball valve to the solar tank (COMPONENT #8) and opening a hot water outlet, such as a faucet, until the water runs freely. When the tank is filled, inspect all threaded fit­tings and solder joints for leaks.
Connect a washing machine hose to the drain ports of the potable flushing combination valves (COMPONENT #24 & 36). Open domestic flushing combination valves drain ports (COMPONENT #24 & 36).
Open potable flushing valve (COMPONENT #36) and close valves drain port when water flows out of the hose. Close domestic flushing valve (COMPONENT #24) drain valve when water flows clear from the hose.
Open potable flushing valve (COMPONENT #24). Check for leaks. The entire potable piping is now pressurized with potable water.
4.14.2 STEP 2 - Flush and Fill the solar loop piping with water.
Close solar flushing combination valves (COMPONENTS #11 & 35).
Connect a washing machine hose to the solar flushing combination valve drain port (COMPONENT #11), open the solar flushing valve drain port (COMPONENT #11). Connect the other end of the hose to a water pressur­ized water source or a utility pressure pump.
Connect a washing machine hose to the solar flushing combination valve drain port (COMPONENT #35), open the solar flushing combination valve drain port (COMPONENT #35). Open the water pressurized water source. Run until clear water runs from the washing machine hose connected to the solar flushing combina­tion valve drain port (COMPONENT #35).
Open the solar flushing combination valves (COMPONENTS #11 & 35). Close the solar flushing combination valves drain ports (COMPONENTS #11 &
35), turn off the water source. Verify water level in drainback tank is within 1 inch from the top of the sight glass or flow mater; fill or drain as necessary.
4.14.3 STEP 3 – Run the pump to check operation and
flush impurities from the collector loop.
At this point it is recommended to run water through the system to remove any solder flux residue or other impurities that were introduced into the system during plumbing. Water soluble flux should have been used when soldering pipe joints in the collector loop to facili­tate system flushing. Set the switch on the side of the
SunEarth control to the “ON” position see (fig 16). Al-
low the pump to circulate water through the system for 15-20 minutes. While the pump is running check the entire collector loop for leaks and ensure that there is adequate flow.
4.14.4 STEP 4 – Check that Collectors are Draining Back.
Turn the controller back to the ‘OFF’ position see (fig
16). Allow time for the collectors and piping to drain into the drainback reservoir. Observe the water level in the drainback reservoir by means of the site glass, visual flow meter or by checking with a dowel rod. The water level in the drainback reservoir should return to the original fill level after a few minutes. If the water level does not return to the original fill level, the sys­tem is not draining properly and may freeze. If water level does not return to original level, check that the collectors are tilted with riser tubes at 15° or more and that all piping is sloped to drain at 2% or more.
4.14.5 STEP 5 - Drain the system to remove impurities.
Drain the cycled water out of the array by placing the hose attached to the solar flushing combination valve drain port (COMPONENT #11) into a service drain or bucket. Open the solar flushing combination valve drain port (COMPONENT #11) and completely drain the water from the system.
CAUTION: THIS WATER MAY BE EXTREMELY HOT!
4.14.6 STEP 6 - Refill the system with water.
Connect a washing ma­chine hose to the solar flushing combination valve drain port (COMPONENT #11) and to a utility pump. Open solar flushing combi­n a t i o n v a l v e s
TABLE 4Design Flow Rates
ARRAY Flow Rate
(GPM)
1 EP/EC-40 1.2
2 EP/EC-21 1.2
(COMPONENT #11 & 35) and then slowly pump de­ionized water into the sys­tem until the water level is
2 EP/EC-24 1.6
2-EP/EC-32 1.9
within 1 inch from the top of the sight glass or flow meter. Run the system pump and verify proper operation and that the water level
returns to “set point” on the sight glass or flow meter
when the system drains (circulating pump off).
5) SYSTEM START-UP PROCEDURES
Throughout the installation procedures outlined in Sec­tion 4, emphasis has been placed on the proper plumb­ing and wiring of the primary system components. The solder and threaded connections also have been visual-
ly inspected for leaks and the solar loop piping has been cleaned and charged. Having successfully com­pleted these tasks it is time to set your system to run automatically.
Set the SunEarth control to the ‘ON’ position. Listen
until you can hear water flowing through the solar loop return piping from the collector.
Place your ear next to the pump and listen for signs of cavitation. Cavitation sounds like sand running through the pump and is caused by the implosion of small air bubbles hitting the pump impeller. Cavitation can dra­matically reduce the life of the pump and the flow set­ting valve (COMPONENT #22) should be used to elimi­nate this condition. If you hear cavitation when the valve is wide open, slowly close the valve until the sound is gone.
5.1 Start Automatic System Operation
Set the SunEarth control to the ‘AUTO’ position see (fig
16). Your system is now set to run automatically whenever solar energy is available to be collected.
6) TWO MODES OF SYSTEM OPERATION
Both single and double tank Torrent Drainback systems are designed to accommodate two separate modes of operation. Your system can either (1) serve as a pre­heater to your conventional electric or gas water heater or (2) be bypassed entirely and run 100% on utility power during inclement weather or when maintenance is required.
Single Tank Operating Instructions:
6.1 Solar Preheat:
Leave the circuit breaker on to your solar storage tank and set the tank thermostat to the lowest acceptable temperature setting. The electric resistance heating element will come on only when the tank temperature falls below the thermostatic set point. If the solar heated water entering the tank is warmer than the thermostatic set point, the electric heating element will not come on. If you have a water heater timer, you may preset the timer to turn the heating element on and off at specified times throughout the day if desired.
6.2 100% Utility Power:
Leave the circuit breaker to your solar storage tank on. In this mode of operation you must turn off the circula­tion pump. To turn the pump off, change the opera-
tional setting from automatic to “off”. Failure to turn
off the pump can quickly damage the pump motor, shaft, bearings or impeller.
Two Tank System Instructions:
6.3 Solar Preheat:
Follow the instructions for the single tank system for setting the thermostat, heating element or gas fired water heater or tankless gas water heater for automat­ic operation. Solar preheat mode operates with the collectors heating the solar storage tank and supplying
this heated water into the auxiliary tank whenever there is hot water draw. The ball valves going to and from the solar storage tank (VALVE # 6 & 7) must be open while the bypass ball valve (VALVE # 5) must be closed. See Figure xxx, Solar Preheat.
6.4 100% Utility Power:
Set the thermostat for the auxiliary electric water heat­er, gas fired water heater or tankless gas water heater to the desired hot water temperature. 100% Utility power mode operates by supplying mains water direct­ly to the auxiliary heater whenever there is hot water draw, bypassing the solar storage tank. Follow the in­structions for the single tank system for setting the thermostat, gas or electric heater for automatic opera­tion. The ball valves going to and from the solar stor­age tank (VALVES # 6 & 7) must be closed while the bypass ball valve (VALVE # 5) must be open. See Fig­ures xxx, 100% Utility Power.
7) SYSTEM SHUT DOWN AND ISOLATION PROCE­DURES
Your Cascade 2 Drainback solar water heating system is designed so that the key components can be easily isolated for emergency repairs or routine maintenance. By shutting a single valve you can isolate the entire system from the pressurized cold water supply line (COMPONENT #8). In the case of a storage tank or fitting leak immediately shut this valve and call your installation contractor for service.
The collector loop can be quickly drained if a leak is detected or for routine maintenance. Set the SunEarth
control to the ‘OFF’ position. Next, attach a hose to the
lower boiler drain (COMPONENT #11) and open the valve to drain the system.
CAUTION: THIS WATER MAY BE EXTREMELY HOT!
In two tank systems the solar storage tank can be iso­lated from the back-up water heater. Set the valve handles to the 100% utility power configuration as out­lined above. By closing these valves the tank can be serviced or replaced. The operation of the back-up wa­ter heater will not be affected.
Remember to reset the SunEarth control to the ‘AUTO’
position upon your return and check the system for proper operation and draining by monitoring the water levels with the pump on and off.
9) MAINTENANCE AND TROUBLESHOOTING
The following simple procedures are intended to opti­mize the performance of your Torrent Drainback solar water heating system and also to extend the life of the primary components.
9.1 Checking the Water Level
It is important that the drainback reservoir remains full for proper system operation. To check the fluid level,
set the SunEarth control to the ‘OFF’ position and allow
the fluid in the array to drain into the drainback reser­voir. For systems installed with an optional flow meter or sight glass, check to see that the fluid is not less
than 1” from the top of the meter. If your system does
not have a flow meter, unscrew the pressure relief valve (COMPONENT #9) and dip a wooden dowel into the threaded copper fitting to check that the fluid level is not more than 6-8” below the valve fitting. If a small amount of fluid is needed to bring the reservoir up to the proper level, pour it directly into the COMPO­NENT #9 fitting port. Rewrap the thread with Teflon tape and reinstall the COMPONENT #9. You may also follow the instructions in section 4.13 for charging the system if more water is required.
Please remember that over time you WILL lose some fluid in the solar loop piping. If the water level is
not properly maintained you may do irreparable damage to your circulating pump. Check your fluid
levels at least once a year.
9.2 Replacing the Anode Rod
The second most important component in your system, at least from a longevity standpoint, is often ignored and never seen. We are referring to the sacrificial
“anode rod” installed in your solar storage tank (ST1).
Typically constructed from magnesium, anode rods are
installed in “glass lined” water heaters and storage
tanks to inhibit corrosion.
8) VACATION RECOMMENDATIONS AND PROCE­DURES
Solar water heating systems can build up very high temperatures during summer months if there is no dai­ly draw on the system. If a short summer vacation is planned the best way to avoid overheating in a drain-
back system is to set the SunEarth control to the ‘OFF’
position. The pump will not circulate during the day and the system will not “gain” any additional heat.
For extended vacations of a month or more SunEarth recommends that you cover the panels with a suitable opaque material. Stagnation conditions can have an adverse effect on the internal collector piping if the
panel is left unprotected. SunEarth’s collector warranty
specifically excludes stagnation conditions in excess of sixty days.
As the name implies, the “sacrificial” anode rod is con-
sumed so that the tank lining is not. At a certain point in the process, the anode rod is no longer completely effective and the corrosive processes begin to eat away
at the tank’s glass lining. In time the solar storage
tank, like any other gas or electric water heater, will begin to leak. The process is not reversible and the tank must be replaced.
System temperatures and water quality affect the rate at which the anode rod is consumed. In general: the higher the average system temperature the faster the rate of corrosion. By changing the anode rod after the fifth year of system operation, and every three to five years thereafter, it is possible to extend the life of the solar storage tank. Periodic replacement of the anode rod in your solar storage tank can significantly extend the tank life.
9.3 Flushing the Storage Tank
The solar storage tank also should be flushed annually to minimize sediment buildup on the bottom of the tank. If you live in an area with high mineral content in your water, flush the tank on a semi-annual basis. Dis­connect the power to the solar tank at the circuit breaker or time switch (if present) before flushing. Set
the SunEarth control to the ‘OFF’ position. In a two
tank system it is not necessary to disconnect the power to the electric water heater in order to flush the solar tank.
Open the flush valve on the bottom of the storage tank and drain a sufficient volume of water to eliminate the sediment. After the procedure is complete make sure the tank is completely full of water before restoring power to the thermostat and heating element. Set the SunEarth control to the ‘AUTO’ position.
9.4 Cleaning the Collector Glass
If you live in a dusty climate it is beneficial to wash off the dirt that settles on the collector glass once a month. Clean glass allows the collector to maintain a high level of thermal performance.
9.5 Maintaining Pipe Insulation
Check the exterior pipe insulation annually and patch or repair any exposed surfaces or degraded areas. Re-
pair as necessary with manufacturer’s recommended
jacket or coating or a high quality exterior latex paint.
9.6 Glass Replacement
In the unusual instance of collector glass breakage, the glass should be replaced immediately. This will reduce the likelihood of water accumulating inside the collector and deteriorating the insulation. Contact your installa­tion contractor to change the glass.
9.7 Leaks
If you detect a water leak in the solar loop piping or tank plumbing, contact your installation contractor to service and refill the system.
ble temperatures at the collector or tank (i.e. 180ºF tank and 45ºF collector), check both sensors using a resistance meter to see if they are correctly calibrated. If you find a defective sensor replace it immediately.
9.10 Auxiliary Electric Element not Operating
If the weather is poor and the auxiliary heating ele­ment will not fire, the bright red reset button on the thermostat may have to be depressed to be reset. Sin­gle tank systems have one heating element and ther­mostat. Double tank systems with conventional elec­tric water heaters have two heating elements and ther­mostats.
DANGER: NEVER REMOVE THE PROTECTIVE AC­CESS PLATE ON THE EXTERIOR OF THE SOLAR STORAGE TANK OR CONVENTIONAL WATER HEATER WITHOUT DISCONNECTING THE 230 VOLT POWER SUPPLY AT THE CIRCUIT BREAKER.
After the circuit breaker has been turned off, remove the access plate on the storage tank or water heater and depress the red reset button on the thermostat. If it clicks when depressed the heating element should fire immediately when you reconnect the circuit break­er. It the reset button does not click and you do not have hot water after one hour, the heating element or thermostat may be defective. Contact your installation contractor for service.
In two tank systems the conventional electric water heater will be wired for electrical back-up. The solar tank will serve solely as a storage tank and will not be wired. After the circuit breaker has been turned off, remove the access plate in the storage tank and de­press the red reset button on the thermostat. If it clicks when depressed the heating element should fire immediately when you reconnect the circuit breaker. If the reset button does not click and you do not have hot water after one hour, the heating element or thermo­stat may be defective. Contact you installation contrac­tor for service.
10) SYSTEM COMPONENTS PARTS
9.8 Pump Not Circulating
If it’s been a sunny day and you don’t have hot water,
first make sure that the controller is set in the auto­matic position. If the controller is properly set and the pump has not been running, unplug the line cord from the controller receptacle and plug the pump directly into a nearby 115 volt outlet. If the pump does not run it may need to be replaced. If the pump does run when plugged directly into the wall outlet, the problem may be located in the controller or one of the tempera­ture sensors. Contact your installation contractor for service.
9.9 Night Time Heat Loss
If you have a full tank of hot water before bed and the solar storage tank is cold in the morning make sure that the circulating pump is not running at night. If the pump is running and the controller displays questiona-
See Figures 11, 12 and 13 for the location of the spe­cific component numbered below.
1. SunEarth Solar Collector(s): Absorbs the sun’s
heat energy and transfers this heat to the heat ex­change fluid (water) circulating through the collector.
2. Collector Sensor (T1): Wired to the control. Works in conjunction with the tank sensor to automati­cally turn your circulating pump on and off at preset temperature differentials.
3. Tank Sensor (T2): Wired to your controller. Works in conjunction with the collector sensor to turn your circulating pump on and off at preset temperature dif­ferentials.
4. Tank Outlet Sensor (T3) - Optional: Wired to your controller, this sensor shows the temperature of the hot water leaving the solar storage tank. This sen­sor is for information purposes only, it does not affect
the control of the system.
5, 6, 7. Solar Tank Bypass Valve Assembly: For two tank systems only. Assembly of three ball valves allows the solar tank to be completely isolated and by­passed in the case of tank failure. When the solar tank is bypassed, water will be heated by the auxiliary heat­er only. Solar bypass valve assembly may also be a combination of two 3-way valves or a single 4-port sin­gle action bypass valve.
8. Mains Supply Line Isolation Valve: When open allows potable water to fill the solar storage tank or back-up water heater. When closed isolates the solar storage tank and back-up water heater from the pres­surized city cold water supply line.
9. Pressure Relief Valve (PRV): Will discharge heat transfer fluid (water) from the collector closed loop at the PR valve pressure setting, (typically 75 – 150 PSI). Under normal operating conditions, the pressure relief valve will not discharge fluid. If this valve opens and water is expelled contact your contractor immediately. This valve also can be manually opened to assist filling or draining the collector loop.
21. Mixing Valve: Automatically blends hot water from the solar storage tank with incoming city cold wa­ter to an acceptable set point. A mixing valve must be installed on every Torrent Drainback solar water heat­ing system. The mixing valve may include and integral check valve to prevent backflow of mixed or hot water into the cold water feed line. When the mixing valve does not include an integral check valve, an external check valve should be placed on the cold feed to the mixing valve. In two tank systems the mixing valve may be located; either at the outlet to the solar stor­age tank; or at the outlet to the auxiliary heater.
22. Pump Throttling Valve: May be partially closed to reduce the flow rate and prevent pump cavitation.
24. Potable Flush Combination Valve: Used to flush the potable loop and isolate the heat exchanger.
35. Solar Flush Combination Valve: Used to flush the solar loop.
36. Potable Flush Combination Valve: Used to flush the potable loop and isolate the heat exchanger.
The PRV protects the collector and all components in the collector loop from pressures in excess of the PRV pressure setting.
WARNING: THE PRESSURE RELIEF VALVE SET­TING MUST NOT BE HIGHER THAN THE MAXIMUM WORKING PRESSURE OF THE COMPONENTS IN THE COLLECTOR LOOP.
10. Drainback Reservoir: An insulated storage res-
ervoir that holds the collector and solar loop piping heat exchange fluid (water) when the circulating pump is off.
11. Solar Flush Combination Valve: Used to charge and drain the solar loop piping.
12. Circulating Pump: Circulates water through the collector and solar loop piping to the hot side of the external heat exchanger.
13. Potable Circulating Pump: Circulates water from the storage tank through the cold side of the ex­ternal heat exchanger.
14. External Heat Exchanger: Transfers heat from the hot water circulating through the solar collector to the potable water circulated through the solar storage tank.
11) ESTIMATED COMPONENT LIFE
You can expect a long and useful like from the primary components in your Cascade 2 solar water heating sys­tem by adhering to the routine service and mainte­nance tips provided above.
The SunEarth solar collectors have a design life of 25 to 30. The solar storage tank should last 12 to 20 years in most areas provided the anode rod is periodically replaced. The circulating pump and differential control should last 10 to 15 years before needing replacement. Like EPA mileage estimates for automobiles, these component design lives represent average figures for system components installed in the United States. Life of your components may vary.
To obtain warranty service, please see the completed Appendix F in the back of this manual with your instal­lation contractor contact information or contact SunEarth Inc. for the name of an authorized service agent near you.
12) SYSTEM OPERATING PARAMETERS
12.1 Collector Loop Pressure
The pressure in the solar collector loop should be within 0 – 20 PSIG.
17. Differential Temperature Controller: Automati­cally turns the circulating pump on and off when there is sufficient heat to be gained in the solar collector.
18. Heating Element & Tank Thermostat: The aux­iliary water heater thermostat controls the temperature setting of the auxiliary heating element.
19, 20. Temperature and Pressure Relief Valve:
Universally required by the plumbing code on water heaters. Will automatically release and dump water at either 150 PSI of pressure or 210° F in temperature.
12.2 Circulation Flow Rate
The flow rate in the collector loop should be 0.5 – 4 GPM when the pump first comes on (filling the collector loop). Once the collector loop is full and water starts to siphon down the return piping the flow rate will nor­mally increase and should be 0.8 – 5 GPM with the sys­tem circulating.
12.3 Temperature Differential
The temperature difference between the collector outlet
sensor (T1) and the solar tank sensor (T2) should be 4 ºF – 30ºF when the system is circulating.
12.4 Fluid Level
The water level when the system is not circulating (pump stopped) should such that the drainback tank not less than 75% full. When the system is circulating (pump running); the water level in the drainback tank should be not less than 25% full. The drainback tank should never be pumped dry in normal operation as this may result in damage to the circulator pump.
APPENDIX A
CASCADE 2 APPROVED COMPONENTS
Solar Collectors – SunEarth Liquid Flat Plate Collectors
Make Series Model Numbers
EP-21 EP-24 EP-32 EP-40
SunEarth Empire, Paint
SunEarth Empire, Chrome
SunEarth SunBelt SB-24-0.75 SB-32-0.75 SB-40-0.75
SunEarth Imperial, Chrome IC-32 IC-40
SunEarth Imperial, Selective IS-32 IS-40
EP-24-0.75 EP-32-0.75 EP-40-0.75 EP-24-1.5 EP-32-1.5 EP-40-1.5
EC-21 EC-24 EC-32 EC-40 EC-24-0.75 EC-32-0.75 EC-40-0.75 EC-24-1.5 EC-32-1.5 EC-40-1.5
SunEarth ThermoRay TRB-32 TRB-40
Collector Mounting Hardware
Make Series
SunEarth
Install mounting hardware per SunEarth manuals, standard residential drawings, and/or plan sets.
SolarStrut; RexRack; Flush Mount Kit; Universal Tilt Kit;
Landscape Rack
Storage Tank
Make Series Model Numbers
SunEarth SunEarth
Any Equivalent UL Listed Tank
*
Includes auxiliary 4.5 kW heating element, suitable for one or two tank systems.
SU80U-1* ; SU120U-1*; SE-80-6*; SE120-6
*
Differential Temperature Controller
Make Series Model Numbers
SunEarth
Steca
Independent
Energy
Goldline GL-30-X216; GL-30-X217
SETR0301U; SETR0502U; SETR0603mcU
SETR A501 T; SETR A502 TT; SETR A503 TTR TR0301U; TR0502U; TR0603mcU
TR A501 T; TR A502 TT; TR A503 TTR
or Approved Equal
APPENDIX A
CASCADE 2 APPROVED COMPONENTS
Heat Exchanger
Make Series Model Numbers
AIC L-Line LA14-10
Drainback Reservoir
Make Series Model Numbers
SunEarth CopperStor DB-2.5; DB-5; DB-7.5; DB-10
SolarH2OT DBT DBT 10 SS; DBT 15 SS; DBT 20 SS
Rheem Energy Miser 81VP6S; 81VP15S; 81VP10S; 81VP20S
A.O. Smith ProMax® EJC-6; EJC-10; EJC-20
Or Approved Equal
APPENDIX A
Solar Storage Tank
The Solar Storage Tank shall be glass lined steel, stainless steel or polymer construction. Tank in­sulation shall be R-12 or higher. The maximum working temperature shall be no less than 180oF and the maximum working pressure shall be no less than 75 psi.
Circulator Pumps
The circulator pump shall be a wet rotor small circulator with a cast iron, stainless steel, brass or polymer body and a metal or polymer impeller. The pump motor shall be induction or permanent magnet ECM driven. The pump shall be rated for: maximum fluid temperatures of no less than 180°F and pressures of no less than 125 PSI. The maximum rated amperage shall be no more than
1.5 Amps and the maximum rated power draw shall be no more than 135 Watts.
Thermostatic Mixing Valve
The thermostatic mixing valve shall have a bronze, brass or stainless steel body with a rated maxi­mum working temperature no less than 200oF and a rated maximum working pressure no less than 125psi. The range of temperature set points shall be at least 18ºF (10ºC) and shall include a set point of 120ºF (50ºC). The Thermostatic Mixing valve shall be third party listed and certified to one of the following ASSE standards: ASSE 1016; ASSE 1017; ASSE 1070.
Ball Valves
Ball valves shall be of bronze, brass or stainless steel construction. Maximum working temperature shall be no less than 200°F and maximum working pressure shall be no less than 125 psi.
Three-Way Valves (Optional)
Three-Way valves shall be of bronze, brass or stainless steel construction. Maximum working tem­perature shall be no less than 200°F and maximum working pressure shall be no less than 125 psi.
Boiler Drains (A.K.A. Charge Valves; Fill Valves; Drain Valves)
Boiler Drains shall be of bronze, brass or stainless steel construction. Maximum working tempera­ture shall be no less than 200°F and maximum working pressure shall be no less than 125 psi.
Pressure Relief Valve
The pressure relief valve shall be of bronze, brass or stainless steel construction with a pressure setting between 30psi and 150psi. The pressure relief valve shall be set to discharge at a pressure below the maximum design pressure of all other components in the collector loop.
Thermometers (Optional)
Thermometers shall be dial or scale type and shall have a metallic body and casing and a glass lens. The range of measurement shall be not less than 30oF to 200oF with an accuracy of +/- 2%. An electronic temperature sensing system may be used in place of dial or scale thermometers (see below).
Temperature Sensors (Electronic)
An electronic temperature sensing system may be used in place of dial or scale thermometers. Temperature sensors shall be shall be of metallic construction and have a maximum temperature
APPENDIX A
rating not less than 200°F. Temperature reading may be via digital readout, LCD screen, internet or other electronic device. The temperatures may be read at the differential controller screen. The range of measurement shall be not less than 30°F to 200°F with an accuracy of +/- 2%.
Sensor Wire:
Sensor wire for temperature sensors or other electronic sensors must be no less than 18/2 AWG. Sensor wire must be insulated; in locations where the sensor wire is exposed to the elements it must be UV resistant and rated for outdoor use.
Piping and Hoses
Piping and Hoses shall be copper tube or corrugated stainless steel with a maximum operating tem­perature of not less than 220oF and maximum working pressure of not less than 125 psi.
Pipe Insulation
Pipe insulation shall have a maximum operating temperature of no less than 220oF. All pipes shall
be insulated to R2.6 or greater, typically this will require a wall thickness of ¾” or greater. When
located in exposed areas, pipe insulation shall be protected with a UV resistant coating or jacket.
Auxiliary Water Heaters
The auxiliary water heater shall be listed by an accredited listing organization.
The specific auxiliary water heater selected for a system should be adequately sized to meet the full hot water load at the residence taking into account the delivered hot water temperature; the mains cold water temperature and the expected hot water usage as per standard water heater sizing guidelines.
APPENDIX C
CASCADE 2 OG-300 SYSTEM LABELS
Labels containing the text below shall be attached to the appropriate valves on all SRCC OG-300 certified sys­tems.
FLUID IDENTIFICATION:
THE HEAT TRANSFER FLUID USED IN THIS SYSTEM IS WATER.
BE EXTREMELY CARFUL WHEN DRAINING THIS FLUID. IT MAY BE DISCHARGED AT A VERY HIGH TEMPERATURE AND PRESSURE.
PLEASE CONSULT SECTION 8 OF YOUR INSTALLATION MANUAL FOR INSTRUCTION ON SHUTTING DOWN AND DRAINING THE SYSTEM.
HEAT EXCHANGER:
THE HEAT EXCHANGER USED IN THIS SYSTEM IS A SINGLE WALL BRAZED PLATE HEAT EXCHANGER
FREEZE LABEL:
THE TORRENT DRAINBACK SYSTEM IS PROTECTED FROM FREEZING BY AUTOMATICALLY DRAINING THE SOLAR COLLECTORS AND EXPOSED PIPING WHENEVER THE CIRCULATION PUMP SHUTS OFF. WHEN PROPERLY INSTALLED AND OPERATED THE SYSTEM IS PROTECTED TO TEMPERATURES AS LOW AS -50° F.
VALVE NO. 8 - COLD WATER SUPPLY ISOLATION VALVE
THIS VALVE IS NORMALLY OPEN AND ALLOWS POTABLE WATER TO FILL THE SOLAR STORAGE TANK. WHEN CLOSED THE SOLAR STORAGE TANK IS ISOLATED FROM THE PRESSURIZED CITY COLD WATER SUPPLY LINE PIPING.
BOILER DRAIN NO. 11 – SYSTEM FILL & DRAIN VALVE
VALVE 11 IS NORMALLY CLOSED. WHEN OPENED IN CONJUNTION WITH PRV (COMPONENT # 9) IT IS USED TO CHARGE AND DRAIN THE SOLAR COLLECTOR LOOP PIPING.
THE HEAT TRANSFER FLUID USED IN THIS SYSTEM IS WATER. NO OTHER FLUID SHALL BE USED THAT WOULD CHANGE THE ORIGINAL CLASSIFICATION OF THIS SYSTEM. UNAUTHORIZED ALTERATIONS TO THIS SYSTEM COULD RESULT IN A HAZARDOUS HEALTH CONDITION.
BE EXTREMELY CARFUL WHEN DRAINING THIS FLUID. IT MAY BE DISCHARGED AT A VERY HIGH TEMPERATURE AND/OR PRESSURE.
APPENDIX C
PRESSURE RELIEF VALVE (COMPONENT #9)
THE PRV WILL AUTOMATICALLY OPEN AND DISCHARGE FLUID OR AIR IN THE EVENT OF THE COLLECTOR LOOP PRESSURE EXCEEDING THE MAXIMUM WORKING PRESSURE OF THE SYSTEM.
WHEN FILLING OR DRAINING THE SYSTEM THROUGH BD, THE PRV IS MANUALLY OPENED OR REMOVED FROM THE COLLECTOR LOOP IN ORDER TO ALLOW AIR TO FLOW IN OR OUT OF THE COLLECTOR LOOP.
VALVE NO. 7 – COLD FEED TO SOLAR TANK ISOLATION VALVE
THIS VALVE IS NORMALLY OPEN. WHEN CLOSED IN CONJUNCTION WITH VALVE NO. 6 IT WILL ISOLATE THE SOLAR STORAGE TANK FROM THE POTABLE WATER SYSTEM.
VALVE NO. 6 – HOT OUTLET FROM SOLAR TANK ISOLATION VALVE
THIS VALVE IS NORMALLY OPEN. WHEN CLOSED IN CONJUNCTION WITH VALVE NO. 7 IT WILL ISOLATE THE SOLAR STORAGE TANK FROM THE POTABLE WATER SYSTEM.
VALVE NO. 5 – SOLAR TANK BYPASS VALVE
THIS VALVE IS NORMALLY CLOSED. WHEN OPENED IN CONJUNCTION WITH CLOSING VALVES NO. 6 & 7 IT WILL ALLOW COLD WATER TO BYPASS THE SOLAR SYSTEM AND FEED DIRECTLY INTO THE AUXILLIARY WA­TER HEATER.
APPENDIX F
APPENDIX F
APPENDIX G
OG-300 Certification Page
Artwork
The Supplier is responsible for having a page in the installation and operation manual(s) with only the following table on it. It can be anywhere in the manual. SRCC will provide the artwork and no changes are allowed.
The solar system installer is to indicate (circle, check, etc.) the system that was actually installed.
This product certified by:
Solar Rating & Certification
Corporation™
www.Solar-Rating.org
SunEarth, Inc.
8425 Almeria Avenue
Fontana, CA 92335
USA
Solar Energy Factor
(SEFD)
SRCC Cert. No.
Model No.
4.1
2.6
1.6
1.9
1.6
2.6
2.8
1.6
1.6
1.3 1
1.1 1
0.9
1.3 1 3
2.3
1.6
1.8
1.6
1.5
2.4
1.6
5.2
3.2
1.8
2.3 2
1.7
3.4 2
30004026 30004025 30004024 30004023 30004022 30004021 30004020 30004019 30004018 30004017 30004016 30004015 30004014 30004013 30004012 30004011 30004010 30004009 30004008 30004007 30004006 30004005 30004004 30004003 30004002 30004001 30004000 30003999 30003998 30003997 30003996 30003995
C2-80-120-TLG C2-64-120-TLG C2-40-120-TLG
C2-48-80-TLG C2-42-80-TLG C2-32-80-TLG C2-64-80-TLG C2-40-80-TLG C2-80-120-2G C2-64-120-2G C2-40-120-2G
C2-48-80-2G C2-42-80-2G C2-32-80-2G C2-64-80-2G C2-40-80-2G
C2-80-120-2 C2-64-120-2 C2-40-120-2
C2-48-80-2 C2-42-80-2 C2-32-80-2 C2-64-80-2 C2-40-80-2
C2-80-120 C2-64-120 C2-40-120
C2-48-80 C2-42-80 C2-32-80 C2-64-80 C2-40-80
The installed system is marked above
APPENDIX H
Service & Warranty Information
Contactor/Installer Information
Name:__________________________________________________
Company:_______________________________________________
Address:________________________________________________
Phone:__________________________________________________
Email:___________________________________________________
System Information
Model Number:___________________________________________
Date Purchased:__________________________________________
Collector Serial Number:____________________________________
For Service and Repair Contact:______________________________
Comments:______________________________________________ ________________________________________________________ ________________________________________________________ ________________________________________________________ ________________________________________________________
8425 Almeria Avenue Fontana CA 92335
Phone: (909) 434-3100 Fax: (909)434-3101
Email: info@sunearthinc.com www.sunearthinc.com
Revised 3-17-2014
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