System Setup; Heating Water Circuit - COMBOMAX ULTRA 12-4.5 Installation Use And Care Manual

3.4 SYSTEM SETUP

Figures 1, 2, 3 and 4 indentifies and show
location of the different components. They also
provide typical heating system installation.
External components location may vary in order
to accommodate specific installation and local
codes and regulation.

3.5 HEATING WATER CIRCUIT

3.5.1 Connecting
piping
The boiler heating
connections are located on the left side (when
facing the unit) and are 1" NPT F.
Unions are recommended on the inlet and outlet
pipes to disconnect the water heater easily for
servicing if necessary.
Dielectric (insulating) unions should be used if
copper-steel connections are made.
Insulate all pipes
especially in unheated areas.
Never plug the pressure relief valve to avoid
creating a hazardous situation.
3.5.2 Flow-check valve
If the heating system uses a single or multiple
circulators without motorized zone valves, a
flow-check valve
minimize gravity flow and heat loss during non-
draw periods. Modern circulators are typically
provided with spring loaded check valve that will
provide adequate protection.
If the heating system uses motorized zone
valves, these will provide adequate protection.
3.5.3 Pressure relief valve
The boiler is delivered with a factory installed
tank pressure relief valve set at 207 kPa (30
psi).
NEVER replace the pressure relief valve by a
higher set pressure one.
Connect the outlet of the relief valve downward
toward a safe location.
NEVER cap or plug a pressure relief valve
outlet. The pressure relief valve is a safety
apparatus and preventing its proper operation
may cause death, injury or property damage.
COMBOMAX™ Installation, use and care manual
the heating water
supply and return
containing hot water,
must be installed
3.5.4 Operating pressure control &
expansion tank
The boiler is equipped with a factory installed,
pressure regulating make-up water equipped
with a flow check valve. This make-up water
allow filling of the boiler tank and the heating
system. It will also maintain a minimal operating
pressure cold pressure of 83 kPa (12 psi). When
operating the COMBOMAX™ Ultra 12 and the
heating system, pressure will vary between 83
kPa and
operating pressure is affected by the type of
heating system and the size of the expansion
tank installed.
The expansion tank role is to compensate for
the heating system water expansion due to its
rise in temperature.
The expansion tank should have a minimum
capacity of 17,5l (4.6 usg). Lager expansion tank
could be required base on the heating system
size (wetted volume) or if the operating pressure
rise above 193 kPa (28 psi).
Expansion tank is generally wall or ceiling
mounted and is directly connected to the boiler
tank using the ½" NPT M connection provided.
3.5.5 Automatic Air Vent
The COMBOMAX™ Ultra 12 has a factory
installed tank automatic air vent. This air vent
function is to vent any air present in the tank.
For proper operation, do not cap or block the air
bleeder outlet.
For proper operation of the heating system, it
may be necessary to add air bleeders to the
to
heating system circuits.
3.5.6 Heating pump
A pump (or circulating pump) not included, is
required for the heating system to deliver
heating fluid (water) to the different heating
zone. Sizing of the pump is base on the heating
system configuration and is done by the installer
(heating technician, plumber, ).
3.5.7 Low temperature heating (Radiant
floor)
A thermostatic mixing valve or a similar device,
offering the same function, must be installed on
a heating system operating at less than 70°C
(160°F) like
thermostatic mixing valve limit the heating fluid
(water) supplied to the system at a preset
appropriated temperature, by mixing hot heating
fluid (water) supplied by the COMBOMAX™
,
(Revision Sept. 2013)
193 kPa (12 psi to 28 psi). The
radiant floor system. The
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