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LP-200 REV. 1.6.15
F. COLLECTOR LOOP PIPE INSULATION
The collector loop supply and return lines must be well insulated with high quality, flexible, closed cell insulation to minimize heat loss.
Wall thickness of pipe insulation should not be less than ¾". 1" wall thickness is required in all areas prone to annual hard freeze
conditions. When it comes to pipe insulation the rule is simple: thicker is better. The specified insulation material is HT/Armaflex or
equivalent.
Whenever possible, slide the insulation material over the pipe without cutting or taping. All butt joints must be sealed with contact
adhesive. HT/Armaflex should be sealed with Armaflex HT 625 adhesive. Use of rigid polyethylene pipe insulation is prohibited.
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 wrapped with PVC pipe wrap or painted with two
coats of high quality water-based acrylic resin coating as supplied by the insulation manufacturer. Foil tape should not be used as it will
fail. The required coating material is Armaflex WB Finish or equivalent. Prior to applying finish, wipe insulation clean with denatured
alcohol. Paint insulation with two coats of finish. Do not tint the finish.
G. COLLECTOR SENSOR PLACEMENT
The collector sensor must be located on the hot water return line as close to the collector as possible. Some collectors have insertion
wells to measure temperatures more accurately at the manifold.
Sensors are typically accurate to +/
– 1/2 °F if properly installed and weatherized. To maximize sensor accuracy, attach the flanged
portion of the sensor to the collector header pipe with a stainless steel hose clamp. Wire nuts used to connect the sensor and low
voltage wiring shall be all plastic, sealed with silicone and thoroughly wrapped in electrician's tape.
The low voltage wiring used to connect the sensors to the controller should be a minimum 18 AWG. The wiring should be bare or tinned
copper, two conductor, PVC insulated, with a PVC UV rated gray jacket suitable for exterior use. Use Eastman Wire & Cable no. 5704,
Beldon Wire and Cable no. 8461 or equivalent.
The sensor must be placed on the solar collector return line as close to the collector header as possible. Place the sensor wire over the
rubber pipe insulation, under the insulation tape or PVC pipe wrap. Thoroughly wrap and weatherize the insulation with electrician's
tape or insulation tape as provided by the manufacturer.
H. AVOID SHADE
Collectors should be located so that shading does not occur between 9 AM and 3 PM local time. Partial shading due to small objects
such as antennas and flues is not of great concern.
I. LOCATION
To avoid long pipe runs, the collector should be positioned as close as possible to the storage tank. Storage tank location should
therefore be considered part of the location requirements of the solar collector. The storage tank should be located as close as possible
to the most frequent draw off points in the building.
J. LIGHTNING PROTECTION
To avoid lightning related damage or electrical safety issues, it is advisable to earth/ground the frame and copper circulation loop of the
collector.
K. GALVANIC REACTION
Zinc galvanized components should NOT be installed in direct contact with stainless steel or aluminum, as galvanic reaction between
metals can cause premature oxidation of the zinc coating, as well as the steel and aluminum underneath.
Avoid using galvanized steel bolts. Use stainless steel components instead. If galvanized components ARE used, avoid direct contact
between two metals by using rubber/plastic separators.
If roof surface is galvanized steel, refer to manufactur
er’s corrugated roof installation guidelines.
L. WIND STRESS
When installing the solar collector(s), please consider the issue of wind resistance and the resultant stress on attachment points.
Adhere to relevant building codes/regulations regarding installation of such objects.
It is the responsibility of the installation contractor to ensure that the frame mounting is of suitable strength. Where applicable,
inspection by building department officer or equivalent should be completed to ensure the installation is in accordance with relevant
regulations.
