Mitsubishi Heavy Industries HMK60, Installation Manual

Page: 225 / 288

19
Pipe installation
Connecting hot water tank to water main
■ Install a mixing valve if the temperature exceeds 60 °C.
■ It is recommended to install a thermostatic mixing valve
for stable temperature hot water supply.
■ Connect the storage tank to the water supply system of
water pressure at least 1 bar and max 10 bar. Install a
pressure reducer if the pressure at the cold water inlet to the
tank is higher than allowed.
■ Install a safety valve which have a maximum 10.0 bar
opening pressure on the incoming domestic water line
according to outline diagram in order to protect the storage
tank against overpressure. Pressure increases during heating
the water.
■ During heating the water, small and temporary water fl ow
from the safety valve can occur, which indicates that the
pressure has increased above the rated value, which
triggered the valve. This may in no way be prevented.
■ Safety valve drain line should be installed with a decline, in
an environment free of freezing and remain open to the
atmosphere. The manufacturer is not responsible for
fl ooding the room through the safety valve.
■ Blocked safety valve can cause equipment failure. Drain
the outfl ow from the safety valve to the sewerage or drain
grate.
■ See section Dockings on page 22 for outline diagram.
■ Connect the water supply system according to the
installation diagram.
Installation diagram of the PT storage tank with one coil.
1
2
2 2
2
6
7
3 8
4 5
DHW
hot water circulation
(optional)
to sewerage
water supply system
1. PT storage tank
2. Cut-off valve
3. Safety valve
4. Drain valve
5. Pressure reducer (option, if the pressure in the system
exceeds the allowable value)
6. Strainer
7. Hot water circulating pump
8. Hot water expansion vessel
Information
In order to minimize the flow of water from the safety valve
associated with the thermal expansion of the liquid, it is
advisable to install a suitable expansion vessel at the cold
water connection (see item 8.)
CAUTION
Installation of the appropriate safety valve in the cold
water supply line protecting the unit against
overpressure is mandatory!
CAUTION
Installation of necking of any kind (such as reducers, dirt pockets,
etc.) and cut-off valves between the storage tank and the safety
valve is not allowed. Only a T-pipe with a drain valve and a T-pipe
with an expansion vessel may be installed in these line sections.
CAUTION
Never block the safety valve or drain line. This can cause
a dangerous overpressure in the storage tank.
CAUTION
When heating water, slight, temporary discharge from
the safety valve can occur. This is a correct safety valve
function. Any attempt to interfere in its operati on can
lead to the danger and destruction of the storage tank.
CAUTION
Never use the equipment with clogged safety valves.
Connection
After the installation and levelling the tank, follow the proce-
dure below (for the connector pipe symbols, refer to page 17):
1. Remove protecting plugs from the connector pipes
2. Connect the hot water intake line (N).
3. Connect the cold water supply line together with the
required safety valves (G).
4. If the system has the hot water circulation system, connect
it to the connector pipe (L). Otherwise, plug the pipe.
5. Connect the supply (J) and return (H) of the heating
medium to the coil.
CAUTION
If there is an electric heating module installed in the
storage tank, fi ll the tank with water before connecting
it to the electrical installation.