WaterFurnace 7 Series - Manual (Page 7)

7
7 SERIES 50Hz 700A11 INSTALLATION MANUAL
seal is in the swivel connector prior to attempting any
connection. The rubber seals are shipped attached to the
waterline. To make the connection to a ground loop system,
mate the brass connector (supplied in CK4LI connector
kit) against the rubber gasket in the swivel connector and
thread the female locking ring onto the pipe threads, while
maintaining the brass connector in the desired direction.
Tighten the connectors by hand, then gently snug the
fitting with pliers to provide a leak-proof joint. When
connecting to an open loop (ground water) system, thread
any 25.4mm MPT fitting (SCH80 PVC or copper) into the
swivel connector and tighten in the same manner as noted
above. The open and closed loop piping system should
include pressure/temperature taps for serviceability.
Never use flexible hoses smaller than 25.4mm inside
diameter on the unit. Limit hose length to 3.1 meters per
connection. Check carefully for water leaks.
Duct System
An air outlet collar is provided on vertical top and rear air
discharge units and all horizontal units to facilitate a duct
connection (vertical bottomflow units have no collar). A
flexible connector is recommended for discharge and return
air duct connections on metal duct systems. Uninsulated
duct should be insulated with a minimum of 25.4mm duct
insulation. Application of the unit to uninsulated ductwork
in an unconditioned space is not recommended as the unit’s
performance will be adversely affected.
If the unit is connected to existing ductwork, check the duct
system to ensure that it has the capacity to accommodate
the air required for the unit application. If the duct is too
small, as in the replacement of heating only systems, larger
ductwork should be installed. All existing ductwork should
be checked for leaks and repaired if necessary.
The duct system should be sized according to the table
below to handle the design airflow quietly and efficiently.
To maximize sound attenuation of the unit blower, the
supply and return plenums should include an internal duct
liner of fiberglass or constructed of ductboard for the first
few meters. On systems employing a sheet metal duct
system, canvas connectors should be used between the
unit and the ductwork. If air noise or excessive airflow is a
problem, the blower speed can be changed.
Model Design Airflow L/s
NVK009 708
NVK012 849.6
NVK015 1038.4
Water Piping
The proper water flow must be provided to each unit
whenever the unit operates. To assure proper flow, use
pressure/temperature ports to determine the flow rate.
These ports should be located at the supply and return
water connections on the unit. The proper flow rate cannot
be accurately set without measuring the water pressure
drop through the refrigerant-to-water heat exchanger.
All source water connections on residential units are swivel
piping fittings (see Figure 4) that accept a 25.4mm male
pipe thread (MPT). The swivel connector has a rubber
gasket seal similar to a rubber hose gasket, which when
mated to the flush end of any 25.4mm threaded pipe
provides a leak-free seal without the need for thread
sealing tape or compound. Check to ensure that the rubber
Figure 4: Swivel Connections
Locking
Ring Stainless
Steel
Snap Ring
Gasket
Support
Sleeve
Gasket
Material
General Installation Information cont.