Gree LSQWRF35VM/NaA-M, Service Manual

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39
Unit Installation
Threads should be processed by the threading machine.
Use lead oil and oakum as stuffing materials and remove those outside of the threads after pipes have
been installed.
Threads should be clean and at least 90% threads should be intact. Two or three spirals of threads
shoud be exposed at the connection joint after installation without any exposed stuffing. Galvanized pipes
should be protected and local damage should take anti-corrosion treatment.
3.4.3 Installation of the expansion tank
An expansion water tank should be installed for the closed-circuit water system to buffer water
expansion and constriction as well as avoid effects on the water pipes caused by makeup water.
(1) After the full water test, surface of the water tank should be de-rusted, finished and treated with ant-
corrosion measure. The artificial anti-rust class should be st3.
(2) After that, when water tank temperature is below 30°C, it should be painted with red lead rust-proof
paint twice. When the temperature is among 30~70°C, it should be painted with chloroethylene 4~5
times. When the temperature is among 70~95°C, it should be painted with heat-resistant anti-rust
paint 4~5 times. Do not do directly welding on the water tank with surface treatment.
(3) The water tank should be installed horizontally and placed at a bar support which should go 100mm
beyond at each side of the base plate. Height of the bar support should be no less than 300mm.
(4) When water pipes are installed in the room without the heating system, the water tank, expansion
pipe, circulating pipe, and signal pipe all should be insulated.
(5) The installation height of the expansion water tank should be in the way that the lowest level of the
water tank is at least 1m above the highest point of the water system.
(6) For the mechanical circulating air-to-water system, in order to keep the expansion water tank and
water system run normally, the expansion pipes of the expansion water tank should connect to the
suction inlet of the circulating water pump. For the gravity circulating system, the expansion pipes
should connect to the top of the main supply water riser pipe.
(7) For the two-pipe air conditioning system, when there is only one expansion water tank for chilled
and hot water, its effective volume should be figured out based on the heating conditions.