Laars mascot ft MFTHW, Installation And Operation Instructions Manual

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LAARS Heating Systems
Page 46
4.15 Pressure Relief Valve
Pressure Relief Valve must be installed on the CH
supply line & DHW outlet line as close to the unit as
possible. (CH supply line: maximum 30psi, DHW
outlet line : maximum 150psi). No other valves should
be placed between the pressure relief valve and the
appliance.
This appliance has a high-temperature shut off switch
built in as a standard safety feature .Therefore a
“pressure only” relief valve is required.
External pressure relief valves must be installed.
Observe the following. Failure to comply with the
guidelines on installing the pressure relief valve and
discharge piping can result in personal injury, death
or substantial property damage.
WARNING
Do not operate this appliance before the
pressure relief valve supplied is installed with
sufficient relieving capacity in accordance
with the ASME Rating Plate on the boiler.
This boiler is provided with 30 psi safety relief valve
that complies with the ANSI/ASME Boiler and Pressure
Vessel Code, Section IV (“Heating Boilers).(Model :
CASE ACME F-82)
This safety relief valve (30 psi) is shipped loose for field
installation.
An approved ASME HV Pressure Relief Valve must be
installed on the DHW supply line as close to the unit
as possible. Valve size 3/4”, maximum 150 psi. Not
included with boiler.
For safety, the relief valve(s) must be installed into it’s
designed location and not be removed or plugged.
Failure to comply with the guidelines on installing the
pressure relief valves and discharge piping can result in
personal injury, death or substantial property damage.
Direct the discharge piping of the pressure relief valve
so that hot water will not splash on anyone or any
nearby equipment. Attach the discharge line to the
pressure relief valve and run the end of the line within
6-12″ (150-300mm) of the floor.
WARNING
DO NOT install a CH pipe line relief valve with a
pressure higher than 30psi and DHW pipe line relief
valve with a pressure higher than 150psi. This is the
maximum allowable relief valve setting for the boiler.
Test the operation of the valve after filling and
pressurizing system by lifting the lever. Make sure the
valve discharges freely. If the valve fails to operate
correctly, replace it with a new relief valve. Ensure that
the discharge capacity of the pressure relief valve is
equal to or greater than the maximum pressure rating
of the boiler.
Ensure that the maximum BTU/H rating on the
pressure relief valve is equal to or greater than the
maximum input BTU/H rating of the boiler.
3/4” 30psi Relief Valve