Safety Guidelines; Description Of Function; Technical Data - Honeywell NK295C Einbauanleitung

1. Safety Guidelines

1. Follow the installation instructions.
2. Use the appliance
• according to its intended use
• in good condition
• with due regard to safety and risk of danger.
3. Note that the appliance is exclusively for use in the appli-
cations detailed in these installation instructions. Any
other use will not be considered to comply with require-
ments and would invalidate the warranty.
4. Please take note that any assembly, commissioning,
servicing and adjustment work may only be carried out by
authorized persons.
5. Immediately rectify any malfunctions which may influence
safety.

2. Description of function

The refilling combination combines backflow preventer, pres-
sure reducing valve and ball valves in one appliance.
The backflow preventer is a safety device in accordance with
EN 1717 to protect the quality of potable water against back
pressure, back flow and back syphonage of non-potable
water from plants and connected equipment..
The backflow preventer is separated in three chambers (inlet,
middle and outlet chamber).
If water is drawn from the downstream system, the backflow
preventer is in flow position. The check valves up- and
downstream are opened and the discharge valve is closed.
If the differential pressure between middle and inlet chambers
is less than 10 % of the inlet pressure, the system discon-
nector moves into disconnect position (back suction). The
inlet side backflow preventer closes and the discharge valve
opens.
The pressure reducing valve reduces the inlet pressure to the
desired set-pressure on the outlet side.
Spring-loaded pressure reducing valves work according to
the force comparison principle. The outlet pressure works
against the spring force. If the outlet pressure drops as a
consequence of drawing water, the now higher spring force
will open the valve.
The inlet pressure has no influence in either opening or
closing of the valve. Because of this, inlet pressure fluctuation
does not influence the outlet pressure, thus providing inlet
pressure balancing.
3. Application
Medium Water without inhibitors
Inlet pressure min. 1.5 bar max. 10.0 bar
Outlet pressure 1.5-6 bar
Liquid category Backflow 3 (slightly toxic materials)
Preventer
Honeywell GmbH
GB

4. Technical data

Installation position
Operating temperature max. 65°C
Connection size
Discharge
Connection size
5. Scope of delivery
The refilling combination consists of:
• Shut off valve, up- and downstream
• Complete backflow preventer with discharge connection,
valve cartridge (incl. integrated check valve and discharge
valve, upstream), integrated strainer upstream (mesh size
approx. 0,5 mm) and check valve downstream
• Complete pressure reducing valve with valve insert, spring
bonnet (including adjustment knob), adjustment spring
and pressure gauge
6. Assembly
6.1. Installations Guidelines
• Install in horizontal pipework with discharge connection
directed downwards
• The installation may not take place in areas or ducts where
poisonous gases or vapours may be present or where floo-
ding can occur
• The installation location must be ventilated well
• The installation location should be protected against frost
and be easily accessible
- Simplified maintenance and cleaning
- Pressure gauge at the pressure reducing valve can be
read off easily
• Provide a straight section of pipework of at least five times
the nominal valve diameter after the pressure reducing
valve (in accordance with DIN 1988, Part 5)
• The refilling combination has an integrated strainer - no
separate strainer necessary
- Refilling combination is protected against malfunction
and corrosion damage resulting from ingress of foreign
bodies, e.g. welding beads, sealing materials, metal
cuttings and rust
5
horizontal pipework with discharge
connection directed downwards
40 mm
1/2" AG
MU1H-1548GE23 R1012