Engineering Specs

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c. Ceramic tiles will have a homologous grid of approximately 3400 needled perforations
that differ not more than +/- 0.001 inch (0.03 mm) in diameter to create a homogeneous
radiant surface.
d. Ceramic tiles will have machined perimeter edges so that the burner panel assembly
requires no gasket material between contiguous tiles.
e. The perimeter of the ceramic tile burner panel will be seated to the heater body utilizing
an innocuous ceramic gasket material.
f. The ceramic tile burner will attain an operating surface temperature of 1740°F (950°C).
The ceramic tiles will be able to withstand temperatures of 1832°F (1000°C).The ceramic
tiles will have an inner porosity of 66% or more to ensure sufficient thermal insulation
between radiant burner surface and mixing chamber.
g. The gas/air fuel will be introduced to the mixing chamber through a single venturi located
at the end of the mixing chamber.
D. Controls and Safeties:
1. General:
a. Each individual ceramic tile burner panel will have solid state direct spark ignition and
flame sensor control that is dedicated to secure the operation of that burner panel
b. Heater gas and ignition controls will be readily accessible for servicing.
2. Ignition and Flame Control:
a. Heater will be complete with a low voltage (25Vac), solid state direct spark ignition and
ionization flame sensing control module. Electrical Rating: 25Vac, 60Hz with current
rating of 0.2A at 25Vac
b. Heater will be complete with an igniter/sensor with separate electrodes for spark ignition
and flame sensing.
c. On call for heat the Fenwal 35-60 control will reset, perform a self check routine, flash the
diagnostic LED for up to four seconds. The gas valve and spark are energized
commencing the trial for ignition period. When flame is detected during the trial for
ignition, spark is shutoff immediately and the gas valve remains energized. The
thermostat and main burner flame are constantly monitored to assure the system
continues to operate properly. When the thermostat is satisfied and the demand for heat
ends, the gas valve is de-energized.
d. Flame Failure - Multi Trial Ignition: Should the main burner fail to light, or the flame is not
detected during the first trial for ignition period, the gas valve is de-energized and the
control goes through an interpurge delay before another ignition attempt. The control will
attempt two additional ignition trials before going into soft lockout and the valve relay is
de-energized.
e. If the thermostat continues to call for heat after 30 minutes the control will automatically
reset and attempt to ignite the burner again.
f. To complete the direct spark ignition system the system will incorporate a gas control,
25Vac transformer, and:
i) For space heating application an Infrared Setback Thermostat as supplied by the
manufacturer of the heater
ii) Or for outdoor patio heating a system control panel as supplied by the manufacturer
of the heater
3. Gas Control:
a. Heater will be complete with a direct ignition gas control with a manual valve, two
automatic operators, and a pressure regulator
Electrical Rating: 24Vac, 60Hz; draw 0.5A with both operators energized
b. The gas control will have an inlet pressure tap and an outlet pressure tap to facilitate
measurement of gas supply and manifold pressures during servicing.
c. Heater will be complete with a ½” pipe nipple and ½” union with ½” female NPT for
connection to the gas supply.