Daikin VRV W T-series - Key Lock

4 Preparation
Installation manual
16
RWEQ96~432TAYCU
VRV W T-Series water-cooled system air conditioner
4P540122-1B – 2018.11
Cooling water
(b)
and
circulation system
Hot water system
(c)
Tendency
(d)
Item
(a)
Circulation
water
Make-up
water
Circulation
water
(68~140°F)
(20~60°C)
Make-up
water
Corrosion Scale
Ionic-state silica (mg SiO
2
/l) <50 <30 <30 ○
Reference items
Iron (mg Fe/l) <1.0 <0.3 <1.0 <0.3 ○ ○
Copper (mg Cu/l) <0.3 <0.1 <1.0 <0.1 ○
Sulfate ion (mg S
2–
/l) — ○
Ammonium ion (mg NH
4
+
/l) <1.0 <0.1 <0.3 <0.1 ○
Residual chlorine (mg Cl/l) <0.3 <0.25 <0.3 ○
Free carbon dioxide (mg CO
2
/l) <4.0 <0.4 <4.0 ○
Stability index 6.0~7.0 — — ○ ○
(a) These items represent typical causes of corrosion and scale.
(b) In a condenser water circuit that uses a closed cooling tower, the closed circuit circulating water and make-up water MUST meet the water quality
standards for the hot water system, and passing water and make-up water MUST satisfy those for the circulation type cooling water system.
(c) Corrosion has a tendency to occur when water temperature is high (104°F (40°C) or higher), and if metals with no protective coating are directly
exposed to water, it would be a good idea to take effective measures against corrosion such as adding a corrosion inhibitor or deaeration
treatment.
(d) The circle marks in the columns indicate a tendency for corrosion or scale to develop.
NOTE
▪ Thesupply water MUSTbeclean tapwater,industrial
water or clean underground water. Do NOT use purified
or softened water.
▪ Do NOT use once-through water. It may cause
corrosion.
4.4.2 Water circuit requirements
INFORMATION
Also read the precautions and requirements in the
"General safety precautions" chapter.
NOTE
Use water pipes compiled with the local and national codes.
▪ Thewaterpressureresistanceofwaterpipingofthisoutsideunit
is 464 psig (3.2 MPa).
▪ The connection port for water piping is located in the front. The
connection ports for drain piping are located in the front and back.
When using the back port, change the cast iron plug from the back
to the front and securely close it.
▪ Inindooruse,pipingworkshouldbesuchthatnowaterdropson
the outer plate.
▪ Thelateral protruding sectionofthe drainpipingshould be short
(within 15-3/4 inch (400 mm)) and installed in a downward
direction.
The diameter of drain pipe should be the same as the diameter of
unit connection (3/8 inch (9.5 mm)) or more.
▪ Thediameterofwaterpipeshouldbethesameasthediameterof
unit connection (1-1/4 inch (31.8 mm)) or more.
▪ Install an air purge valve in the midway of the water piping to
prevent cavitation.
▪ Aftercompleting the drainpipingwork, make surethat the water
runs smoothly without any clogging by dust.
▪ Donotconnectthedrainoutlettothewateroutlet.
▪ Installa strainer (standardaccessory)in theinletof water piping
within a distance of 4.9 ft (1.5 m) from the outside unit.
(If sand, waste or rust particles are mixed in the water circulation
system, metal materials will become corrosive.)
▪ Install insulation on the inlet/outlet of water piping to prevent
condensation and freezing.
At installing insulation on water in/outlet pipe, use Polyurethane
foam thickness 3/16 inch (5 mm) for insulation of water piping
socket on heat exchanger.
▪ Installinsulationuptothebaseofheatexchangerasshowninthe
figure 6.
▪ Install a gate valve for chemical cleaning in an easy position to
handle.
▪ Usewaterpipescompliantwiththelocalandnationalcodes.
▪ Runthewaterpumptoflushinsideofwaterpiping.
Then, clean the strainer.
▪ If there is a possibility of freezing, take measures to prevent
freezing.
▪ Connectwaterpipingandheatexchangerviapipeadaptor
(accessory)(ISO228-1•G1-1/4B→ANSI-ASMEB1.20.1•
1-1/4-11.5NPT)
▪ Tighten securely the connection of water piping and socket with
tightening torque of 220 ft·lbf (300 N·m) or less.
(If a large torque is applied, the unit may be damaged.)
Example:
≥
3.15 inch (80 mm)
b
m g
d
e
e
a
j
n
k
c
l
i
f h
a Air purge (field supply)
b Water outlet
c Water inlet
d Shut-off valve (field supply)
e Water connection
f Water piping (field supply)
g Insulation (field supply)
h Pipe adaptor (accessory)
i Heat exchanger
j Strainer (accessory)
k Drain valve (field supply)
l Drain connection
m Insulation cover
n Flow switch (field supply)