HTP Drain Back, Установка, Запуск, Обслуживание, Запчасти, Гарантия

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lp-585 Rev. 000 Rel. 001 Date 9.10.18
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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.
• If the collector stagnation temperature is below 210
o
F, PEX
can be used without a length of copper pipe between the
collector and the PEX.
Penetrations through walls or other surfaces shall not allow
intrusion by insects and/or other vermin. Ensure that all structural
penetrations are properly sealed with an elastomer, such as Tremco
“POLYroof”.
Piping in new solar installations may have dirt, grease, solder
flux, or other impurities that will affect the quality of HTF over
time. Thorough cleaning is required before charging new solar
installations with glycol.
All vertical piping between the drain back tank and collector shall
be supported at each story or at maximum intervals of ten (10) feet.
In addition, all non-vertical solar collector piping should pitch 1/4”
per foot down to the drain back tank to facilitate proper drainage.
Ensure that there are no dips or low points in solar piping that
could trap fluid and possibly rupture in freezing conditions. Copper
plumbers tape or tube strap is the required strapping material. The
pipe insulation may not be compressed or crimped by the strapping
material.
The installation of all piping may not reduce the performance or
rating of structural members or fire rated assemblies and must
adhere to all applicable local codes and ordinances.
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 hot out line as
close to the collector header as possible, or inserted into a sensor
well near the hot out line. 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.
Figure 2 - Sensor Cable Detail
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. This reaction could
lead to structural failure, property damage, severe personal injury,
or death.
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 manufacturer’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.
M. Snow Load
In areas prone to heavy snowfall, the solar collector(s) should ideally
be installed at an angle of 50° or greater to help promote snow sliding
off the collectors. In addition, it is advisable to raise the lower collector
frame off the roof surface 6 – 8 inches or higher. Doing this places the
collector above moderate snowfall accumulation and allows drifting
snow to more easily slide out from under the collector, which helps
ensure that snow does not cover the collector array.
Please refer to local regulations regarding snow loading precautions.