2nd stage house connection typ: HAGZ-30-„f“ with gas meter

• including 2nd stage low pressure regulator NDR-320
• mounted in the hot-dip galvanised house connection box AP-3 (H/W/D: 490 x 490 x 235 mm)
• including insulator
• including test connection on the inlet and outlet side
• including shut-off valves on the inlet and outlet side
• including single-tube diaphragm gas meter and mounting plate
• including fastening material
• the house connection box is supplied with a removable bonnet and a base plate, thus ensuring easy installation
• optionally available with gas flow monitor
• Input and output connection also others on request

Low pressure regulator – PN 4
Mg: 24 kg/h – Pd: 50 mbar – OPSO: 132 mbar – PRV: 150 mbar
DVGW approved: According to EN 16129/ CE approved according to 2016/426/EG

TYP NDR-320 with OPSO and PRV

DESCRIPTION
The Type 320 pressure regulator is a 2nd stage pressure regulator that reduces the regulated pressure from the 1st stage pressure regulator to a fixed outlet pressure. A safety shut-off valve (OPSO) is mounted on the regulator and a safety relief valve (PRV) is integrated in the low-pressure regulator as safety equipment.

A. INDIVIDUAL DESCRIPTIONS
1. safety shut-off valve (OPSO)
The OPSO is open during normal operation and has the function of automatically shutting off the gas flow as soon as the set response pressure is reached. It must be opened manually after closing.

2. 2nd stage pressure regulator
The pressure regulator reduces the regulated pressure from the 1st stage pressure regulator to a fixed outlet pressure.

3. safety relief valve (PRV)
The PRV is closed during normal operation and has the task of automatically releasing the gas flow as soon as the pressure in the system to be protected has reached the set pressure.
It closes again automatically when the pressure drops below the set pressure.

B. MODE OF OPERATION
The pressure regulator reduces the regulated pressure from the 1st stage pressure regulator to a nominal 50 mbar.
If the outlet pressure at the regulator rises to an impermissibly high level, the response pressure of the safety shut-off valve (OPSO) is reached, which then closes automatically and shuts off the gas flow upstream of the pressure regulator. The respective operating status of the OPSO can be seen on the visual display.

Clear = open
Red = closed

If there is a further increase in pressure, e.g. due to the OPSO not closing completely, the safety relief valve (PRV) automatically releases a limited amount of the gas flow to the atmosphere after the set response pressure has been reached.

C. ASSEMBLY
1. Outdoor installation “f”
In this case, the pressure regulator is installed on the building in front of the house inlet in a house connection box.

2. Indoor installation “t”
If the pressure regulator is installed inside the building, a thermally triggered shut-off device (fuse) must be connected upstream of it.
It is essential to ensure that a blow-off line is led from the PRV to the outside. The ventilation opening or blow-off line must always be
must always be open, otherwise the OPSO will lock due to pressure increase.

D. START-UP
Start-up is carried out by slowly opening the extraction valve on the liquid gas container.
If the OPSO has locked, the following steps are required:

• Close the extraction valve on the liquid gas container
• Relieve the pressure at the pressure regulator (inlet and outlet).
• Twist off the plastic cap of the OPSO
• Pull out the OPSO plunger until it engages.
• Screw the plastic cap back on
• Slowly open the extraction valve on the liquid gas container.

E. FUNCTION TEST OF THE PRESSURE REGULATOR

• Check the inlet pressure: test connection G1/4
• Checking the outlet pressure: test port G1/8
• Set pressure and function test of OPSO/PRV: test port G1/8