Laars NTH1000, Installation And Operation Instructions Manual, Page: 24 / 140

LAARS Heating Systems Page 20
Suggested piping diagrams are shown in Figures
12 through 16. These diagrams are meant only as
guides. Components required by local codes must be
properly installed.
The NeoTherm LC’s efficiency is higher with
lower return water temperatures.
Therefore, to
get the best low return temperature with multiple
boilers, pipe as shown in Figures 15 and 16.
6A.2 NTH Cold Water Make-Up
1. Connect the cold water supply to the inlet
connection of an automatic fill valve.
2. Install a suitable back flow preventer between
the automatic fill valve and the cold water
supply.
3. Install shut off valves where required.
In some installations, a hot water heating boiler is
connected to heating coils located in an air handling
appliance where the coils may be exposed to
refrigerated air circulation. In these cases, the boiler
piping system must be equipped with flow control
valves or other automatic means to prevent gravity
circulation of the boiler water during the cooling
cycle.
A boiler installed above radiation level, or as
required by the authority having jurisdiction,
must be provided with a low water cutoff device
either as a part of the boiler or at the time of boiler
installation.
NTH PIPE SIZE, NTV PIPE SIZE,
SIZE INCHES SIZE INCHES
1000 2 1000 2
1700 2.5 1700 2.5
Table 9 - Water Connection Pipe Sizes
Section 6 -
WATER CONNECTIONS
Section 6 is divided into TWO parts.
Section 6A covers NTH units designed
for hydronic heating. Many installations
include indirect domestic hot water.
Section 6B covers NTV models, which are
designed exclusively for “volume water”
domestic hot water applications. Refer
to the proper section for instructions on
installing and piping your product. Refer
to Table 9 for the connection pipe sizes
required.
Section 6A - NTH Systems
6A.1 NTH System Piping:
Hot Supply Connections
Note - This appliance must be installed in a closed
pressure system with a minimum of 12 psi (82.7
kPa) static pressure at the boiler.
The hot water piping should be supported by suitable
hangers or floor stands. Do not support the piping
with this appliance. The hangers used should allow
for expansion and contraction of copper pipe. Rigid
hangers may transmit noise through the system
resulting from the piping sliding in the hangers. We
recommend that padding be used when rigid hangers
are installed. Maintain 1” (2.5 cm) clearance to
combustibles for all hot water pipes.
Pipe the discharge of the relief valve (full size) to a
drain or in a manner to prevent injury in the event
of pressure relief. Install an air purger, an air vent,
a diaphragm-type expansion tank, a hydronic flow
check in the system supply loop, and any other
devices required by local codes. The minimum fill
pressure must be 12 psig (82.7 kPa). Install shutoff
valves where required by code.