HTP PHE199-119S - Manual (Page 23)

23
LP- 204 REV. 3.25.14
In order to meet health and safety regulations, solar system antifreeze fluid should be food grade polypropylene glycol, FDA rated as
“generally recognized as safe” (GRAS). Using proper concentrations of glycol, solar systems can be operated at ambient temperatures
as low as -60
o
F. Freeze tolerance limits are based upon an assumed set of environmental conditions. Refer to the DOWFROST
specification sheet in the back of this manual for recommended concentrations. If using a glycol/water mix, the water must meet the
above requirements, and the glycol content of the liquid must not exceed 50%, unless the manufacture specifies that a different ratio is
recommended for use with solar water heaters. Glycol may need to be changed periodically (every 3-5 years) to prevent it from
becoming acidic; please refer to the guidelines provided by the glycol manufacturer regarding replacement.
B. FLUID SAFETY LABELING
Included with your solar system is a set of labels which describe component function. These labels alert the owner to potential hazards.
Affix these labels by string/wire/tie on valves, and/or “peel and stick” on pipe insulation. Labels on the solar loop system must contain
the following warning:
“No other fluid shall be used that would change the original classification of the system. Unauthorized alterations to this system could
result in a hazardous health condition.”
All labeling MUST be in place at final inspection.
C. FREEZE PROTECTION
“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 the Supplier’s instructions if the air temperature is expected to approach the specified freeze
tolerance limit.”
For areas with temperatures not falling below
–5 o C / 23 o F, a simple low temperature controller may be used to guard against freezing.
If necessary, backup freeze protection in the form of an uninterrupted power supply (UPS) or freeze valves (which open to allow water
to dribble out) should also be installed.
For areas with temperatures that fall below
–5 o
C / 23
o
F, a closed loop filled with a polypropylene glycol-water mix should be used to
provide hard freeze protection. Please refer to glycol manufacturer’s specifications about the temperature ranges the liquid can
withstand. Only food grade polypropylene-glycol, FDA rated as GRAS, should be used.
NOTE: HTP DOES NOT WARRANT THE SOLAR COLLECTOR OR ANY COMPONENTS AGAINST FREEZE RELATED DAMAGE.
PART 8 – START-UP PREPARATION
DO NOT MOVE ON TO THESE STEPS UNTIL THE ENTIRE SOLAR SYSTEM, INCLUDING ALL PIPING, SOLAR COLLECTORS,
SENSORS, PUMP, CONTROLS, AND ELECTRICAL CONNECTIONS, ARE PROPERLY SECURED, INSULATED, LABELED AND
INSTALLED.
A. CHARGING THE SYSTEM
Solar Water Heater
Fill the solar tank with water. Do this by opening the cold water isolation ball valve to the solar tank. See Part 6 - Piping for valve
locations. Inspect all fittings for leaks.
Solar Collector
The solar collector loop should be pressure tested with air (25 psi) before you pressurize the loop with HTF. If using glycol, mix in
accordance with the glycol manufacturer’s data sheet. The charging process will require a low flow diaphragm pump to fill and
pressurize the collector loop.
Connect the discharge side of the pressure pump to the fill valve. See Part 6 - Piping. Place the pump suction side hose in the glycol
solution. Close the ball valve (#11). Connect a second hose to the drain valve (#10) and place the other end of the hose in the empty
bucket.
TOTAL COLLECTOR LOOP FLUID CAPACITY IN GALLONS*
1. Collector System 3.5 gallons
2. Collector System 4.5 gallons
*Assumes a total 100’ pipe run using ¾” Type M hard copper tubing.
The solar water heater heat exchanger has a 1.75 gallon fluid capacity.
Open the upper fill valve (#18) and allow the pressure from the expansion tank to push the water in the loop back to prime the pressure
pump. When the hose in the bucket containing the HTF stops bubbling, you may begin charging the collector loop. With both fill and