7
8.
PLUMBING FIXTURE
Connection of heaters to plumbing fixtures is illustrated on Figures 1 and 2. For potential disconnection of
the heater, the service water inlets and outlets must be provided with screw coupling Js 3/4“. Safety valve is
mounted on the cold water inlet identified with a blue ring.
Each hot service water pressure heater must have a membrane spring loaded with a safety valve. Nominal clearance
of safety valves is defined in the ČSN 0 60830 standard. The heaters are not equipped with a safety valve. The
safety valve must be easily accessible, as close to the heater as possible. The input pipes must have at least the
same clearance as the safety valve. The safety valve is placed high enough to secure dripping water drain by
gravity. We recommend mounting the safety valve onto a branch pipe. This allows easier exchange without having
to drain the water from the heater. Safety valves with fixed pressure settings from the manufacturer are used for the
assembly. Starting pressure of a safety valve must be identical to the maximum allowed heater pressure, and at least
20% higher than the maximum pressure in the water main. If the water main pressure exceeds such value, a
reduction valve must be added to the system.
No stop valves can be put between the heater and the safety valve.
During the assembly, follow the guide provided by the safety equipment manufacturer. It is necessary to check the
safety valve each time before putting it into operation. It is checked by manual moving of the membrane from the
seat, turning the make-and-break device button always to the right. After being turned, the button must click back
into a notch. Proper function of the make-and-break device results in water draining through the safety valve outlet
pipe. In common operation, such a check needs to be implemented at least once a month, and after each heater
shutdown for more than 5 days. Water may be dripping off the drain pipe of the safety valve; the pipe must be open
into the air, pointed down; environment temperatures must not drop below zero.
When draining the heater, use a recommended
drain valve. First, close water input into the
heater.
Find necessary pressure values in the following
table.
For proper safety valve operation, a backflow
valve must be mounted on the inlet pipes,
preventing spontaneous heater draining and hot water penetrating back into the water main.
We recommend that the hot water distribution from the heater was as short as possible to minimise heat losses.
Heaters must be provided with a discharge valve
mounted on the cold service water inlet to the heater (Fig. 2)
for potential disassembly or repair.
When assembling the security equipment, follow ČSN 06 0830.
9.
ELECTRIC INSTALLATION
The electric wiring scheme is attached to the water heater on the side of the electric installation guard (see also
Fig.).
Connection, repairs, and wiring inspections may only be implemented by a company (person) authorised to such
activity.
Expert connection must be confirmed on the warranty certificate.
The heater is connected to the 400 V/50 Hz electric network using a fixed moving conductor with a switch that
turns off all network poles and the circuit breaker (protector).
Installations in bathrooms, laundromats, rest rooms, and showers, 33 2000-7-701 must be obeyed.
The degree of protection of electric parts of the heater is IP 45.
Respect the rules of protection against electrical injuries in accordance with ČSN 33 2000–4-41.
Wiring scheme:
Safety valve
starting pressure
(MPa)
Admissible operating
water heater
pressure (MPa)
Max. pressure in
the cold water pipe
(MPa)
0.6
0.6
up to 0.48
0.7
0.7
up to 0.56
1
1
up to 0.8
