HTP Drain Back, Installation, Start-Up, Maintenance, Parts, Warranty

Page: 10 / 27

lp-585 Rev. 000 Rel. 001 Date 9.10.18
10
B. Water Chemistry Requirements
Chemical imbalance of the water supply may affect efficiency and
cause severe damage to the appliance and associated equipment.
Water quality must be professionally analyzed to determine whether
it is necessary to treat the water. Various solutions are available to
adjust water quality. Adverse water quality will affect the reliability
of the system. In addition, operating temperatures above 135
o
F will
accelerate the build-up of lime scale and possibly shorten appliance
service life. Failure of an appliance due to lime scale build-up, low
pH, or other chemical imbalance IS NOT covered by the warranty.
The water must be potable, free of corrosive chemicals, sand, dirt,
and other contaminates. It is up to the installer to ensure the water
does not contain corrosive chemicals or elements that can damage
the heat exchanger. Potable water is defined as drinkable water
supplied from utility or well water in compliance with EPA secondary
maximum contaminant levels (40 CFR Part 143.3). If the water contains
contaminants higher than outlined by the EPA, water treatment is
recommended and additional, more frequent maintenance may be
required.
If you suspect that your water is contaminated in any way, discontinue
use of the appliance and contact an authorized technician or licensed
professional.
• Water pH between 6.5 and 8.5
• pH levels below 6.5 can cause an increase in the rate of
corrosion. pH of 8.5 or higher can potentially cause lime
scale build-up
• Maintain water pH between 6.5 and 8.5. Check with litmus
paper or have it chemically analyzed by a local water
treatment company.
• If the pH is not between 6.5 and 8.5, consult a local water
treatment company for solutions.
• Hardness less than 7 grains (120 mg/L) (Commercial Use -
water temperatures of 140
o
F and greater)
• Hardness levels above the required amounts can lead to lime
scale build-up throughout the system. Water below 5 grains/
gallon (85 mg/L) may be over softened.
• Consult local water treatment companies for unusually
hard water areas (above the required amounts) or for other
treatment solutions if water is being over softened (below 5
grains/gallon [85 mg/L]).
• Chloride concentration less than 100 ppm (mg/L)
• Do not fill appliance or operate with water containing
chlorides in excess of 100 ppm (mg/L).
• Using chlorinated fresh water should be acceptable as levels
are typically less than 5 ppm (mg/L).
• Do not connect the appliance to directly heat swimming
pool or spa water.
• Total Dissolved Solids (TDS) less than 500 ppm (mg/L)
• Total dissolved solids are minerals, salts, metals, and charged
particles that are dissolved in water.
C. Solar Heat Exchanger Piping
Set up the primary balance of the system components following the
piping detail in Figures 7 and 8.
Run ½” type M or larger copper pipes, or flex line sets, to and from
the collector following the direction of supports, penetrations, and
other relative items.
Copper or PEX may be used in the solar loop piping of drain back
systems.
When making a connection to the heat exchanger, use Teflon Tape
and joint compound to prevent leaks. Do not apply heat directly to
the heat exchanger thread connection when sweating fittings.
Line pressure and temperature gauge 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 – 12
o
F warmer than the water
in the collector supply line. Compare the temperature readings in
the two line thermometers. The ¾” cold water supply line to the
storage tank must be insulated with a minimum 7/8” x ½” pipe
insulation to a minimum distance of 5’ behind the storage tank, or to
the wall if closer than 5’.
D. Necessary Components for Water Heater Installation
Listed below are components needed for installation of the solar
water heater.
Solar Collector
Absorbs and transfers the sun’s energy into the solar heat exchanger
located on the bottom of the solar water heater.
Solar Air Release Vent*
This air vent allows air contained in the solar system to release.
*Remove and cap the solar air release vent after commissioning the
system.
Solar Collector Sensor
This sensor is wired to the solar controller and automatically turns
on the circulator pump when the differential set point is reached
between the solar water heater and collector.
Solar Temperature and Pressure Gauge
The solar temperature and pressure gauge displays the actual
temperature and pressure supplied and returned to the solar
collector.
Check Valve
Helps minimize convective heat loss at night when the system is not
operating. If a check valve is not installed, most of the heater energy
stored during the day would be transferred into the collector and
lost.
Collector Isolation Valve (Valves #6 and 11)
Valves #6 and 11 isolate the collector loop from the solar water
heater.
Pressure Relief Valve (for Solar System)
Releases pressure in the solar loop when it exceeds 150psi. Contact
your installation contractor immediately if this valve opens and
releases fluids.
so it is recommended that the connections be made with brass unions.
You must use copper and brass fittings in plumbing the solar storage
tank and expansion tank. The use of galvanized fittings, nipples,
dielectric unions, CPVC, PVC, or other plastic pipe is prohibited.
Hard copper connections to the city cold water supply line and 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, a drip or leak may cause
serious damage to the tank’s electrical components, or, in extreme
cases, cause the tank to leak from the outside in.
• The greater the amounts of TDS present, the higher the
corrosion potential due to increased conductivity in the
water.
• If using softened water to fill the appliance, it is still
possible to have high TDS. This water can be corrosive.
Consult local water treatment companies for other
treatment solutions to reduce this affect.
*NOTE: To promote appliance service life, it is strongly
recommended to follow the maintenance procedures in this
manual.