LAARS NeoTherm NTV1000 - Install and Operating Manual - Manual (Page 22)

LAARS Heating Systems
Page 18
The NeoTherm unit’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 14 and 15.
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.
6a.3 ntH freeze Protection
WarnInG
Glycol must not be used in domestic hot water
applications. Refer to Section 6B.4 for instructions
on freeze protection for NTV units (domestic hot
water).
NeoTherm units may be installed indoors or
outdoors. If installed outdoors, the NTH unit
must never be installed in a location which may
experience freezing temperatures. If installed
indoors, and there is an event such as a power
outage, interruption of gas supply, failure of system
components, activation of safety devices, etc., this
may prevent a boiler from firing. Any time a boiler
is subjected to freezing conditions, and the boiler
is not able to fire, and/or the water is not able to
circulate, there is a risk of freezing in the boiler
or in the pipes in the system.
When water freezes,
it expands. This may result in bursting of pipes, or
damage to the boiler, and this could result in leaking
or flooding conditions.
ntH PIPe SIze, ntV PIPe SIze,
SIze InCHeS SIze InCHeS
1000 2 1000 2
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 pipe sizes required.
Section 6a - ntH UnItS
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.
Suggested piping diagrams are shown in Figures
11 through 15. These diagrams are meant only as
guides. Components required by local codes must be
properly installed.