Installation guide

INSTALLATION SECTION 3
Fenwal 35-655305-121 Hot Surface Ignition Control, CE listed. 3 Trials for Ignition,
15 second pre-purge timing, 15 second igniter heat up time, 4 second trial for ignition.
24 volt input to control.
Omron G2R-1A-T-AC24 relays (VDE listed) used for high voltage switching of hot surface
igniter and combustion blower from the 24 volt outputs of the Fenwal control.
Saint Gobain 230 volt hot surface mini igniter.
Honeywell VK8115 gas valve (negative pressure regulator) with matched venturi sizes for
mixing gas with combustion air.
EBM RG130 (36-6 and 43-9KW/hr input sizes) and RG148 (58-3 through 85-0 KW/hr. inputs)
pre-mix combustion blowers. 230 volts, 50/60 Hz.
Burner: Acotech (Bekaert Combustion Technology) Pre-mix burner with stainless steel mesh
outside knit.
Blocked Vent Pressure Switch: Honeywell IS20378-5770 normally closed pressure switch.
Contacts open in the event of a severe blockage of the flue outlet.
Honeywell L6189A 2043B aquastat. Temperature adjustment range: Below 40ºC to
maximum of 82ºC (dial stop to limit maximum temperature). Differential set to 4ºC.
Capillary bulb inserts into well in top of tank. Thermostat dial adjustable on top front section
of water heater jacket.
Honeywell L6189C 2023 1 High limit control. Setpoint fixed to 93ºC with screw. Mounted
to control panel inside control compartment. Capillary bulb inserts into separate well in top
of tank. Manual reset control button accessible through clearance hole in control panel.
Burner fires down into 8” diameter flue tube transferring the radiant heat from the burner
flame into the tank water.
1st Pass Flue Collector: At the bottom of the tank, a refractory lined heavy gauge flue
collector re-directs the flue gases from the 8” flue tube to pass through two 4” diameter flue
tubes to the top of the tank.
4” diameter flue tubes have stainless steel baffles to turbulate the flue gases to improve heat
transfer.
2nd Pass Flue Collector: At the top of the tank, the flue gases from the 4” flue tubes collect
in a heavy gauge steel collector to redirect the flue gases down eight 2” diameter flue tubes.
2” diameter flue tubes are glass lined on the inside as well as outside to prevent corrosion
from flue gas condensate. Stainless steel flue baffles inside the 2” flue tubes turbulate the
flue gases to aid heat transfer. Flue temperatures are reduced from 260-340ºC from the
second pass collector to 54ºC or less in the flue exhaust.
3rd Pass Collector: The flue gases from the bottom of the 2” flue tubes are collected at the
bottom of the tank in a stainless steel flue collector, where the exhaust gases and condensate
exit out through a short Stainless Steel pipe extending outside the jacket that connects to the
coaxial concentric flue system.
IGNITION SYSTEM
COMPONENTS
THERMOSTAT
AND HIGH LIMIT
CONTROLS
HEAT EXCHANGER
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