LAARS Mighty Therm2 MT2V (Sizes 500–2000 MBTU/h) - Install and Operating Manual - Manual (Page 14)

LAARS Heating Systems Page 14
SECTION 4A.
Water Connections — Boiler
4A.1 Heating System Piping:
Hot Supply Connections — Boiler
NOTE: This appliance must be installed in a closed
pressure system with a minimum of 12 psi (82.7kPa)
static pressure at the boiler.
Hot water piping should be supported by suitable
hangers or floor stands. Do not support piping with
this appliance. Due to expansion and contraction of
copper pipe, consideration should be given to the type
of hangers used. Rigid hangers may transmit noise
through the system resulting from the piping sliding in
the hangers. It is recommended that padding be used
when rigid hangers are installed. Maintain 1" clearance
to combustibles for 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, and a hydronic flow
check in the system supply loop. Minimum fill pressure
must be 12psig (82.7kPa). Install shutoff valves where
required by code.
Suggested piping diagrams are shown (see Figures
6 through 10 ). These diagrams are meant only as a guide.
Components required by local codes must be properly
installed.
4A.2 Cold Water Make-Up — Boiler
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.
NOTE: The boiler, when used in connection with a
refrigeration system, must be installed so the chilled
medium is piped in parallel with the boiler with
appropriate valves to prevent the chilled medium from
entering the boiler.
The boiler piping system of a hot water heating
boiler connected to heating coils located in air handling
appliances where they may be exposed to refrigerated air
circulation 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.
4A.3 Water Flow Requirements — Boiler
A hydronic heating (closed loop) application
re-circulates the same fluid in the piping system. As a
result, no new minerals or oxygen is introduced into the
system. To ensure a proper operating temperature leading
to long boiler life, a flow rate has been established based
on the fluid temperature rise for this specific size boiler.
Pump-mounted boilers can be ordered for use in
primary secondary piping systems. The pumps used are
sized for the headloss through the heater, plus 30 feet
(9.1m) of full-sized piping (same size as boiler outlet)
and a normal number of fittings.
Table 8 specifies water flow rates for boilers, which
will enable the user to size a pump. The headloss shown
is for the heater only, and the user will need to add the
headloss of the system piping to properly size the pump.
The minimum inlet water temperature for the
Mighty Therm2 is 120°F (49°C) to avoid condensing on
the copper coils.
4A.4 Freeze Protection — Boiler
Boiler installations are not recommended in
areas where the danger of freezing exists unless proper
precautions are made for freeze protection. A non toxic,
heating system, anti-freeze may be added to the hydronic
system provided that the concentration does not exceed
50% and the anti freeze contains an anti foamant.
When a 50/50 mixture is used, increase the water
flow requirements by 15%, and increase the headloss
requirements by 20%.
Power outage, interruption of gas supply, failure
of system components, activation of safety devices, etc.,
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 can
result in bursting of pipes in the system, or damage to
the boiler, which could result in leaking or flooding
conditions.
IMPORTANT NOTES: Different glycol products may
provide varying degrees of protection. Glycol products
must be maintained properly in a heating system,
or they may become ineffective. Consult the glycol
specifications, or the glycol manufacturer, for information
about specific products, maintenance of solutions, and
set up according to your particular conditions.
SECTION 4B.
Water Connections —
Water Heaters
4B.1 Water System Piping —
Water Heater
Hot water piping should be supported by suitable
hangers or floor stands. Do not support piping with this
appliance. Due to expansion and contraction of copper
pipe, consideration should be given to the type of
hangers used. Rigid hangers may transmit noise through
the system resulting from the piping sliding in the
hangers. It is recommended that padding be used when
rigid hangers are installed.