Install Instructions

Part Number 550-142-902/1016
CGi
GAS-FIRED WATER BOILER — SERIES 3 — Boiler Manual
37
Operation — sequence
9a
Department of Energy – Compliance
9
1. Read Operating instructions on page 41. This information
is also located on a label on the inside of the boiler jacket door
panel.
2. Raise room thermostat to call for heat.
a. While attempting to satisfy the heat demand, the
control module monitors the boiler temperature
changes via the water temperature sensor and deter-
mines whether or not the available hot water will
satisfy the demand, only running the circulator.
If additional heat is needed, the sequence continues.
  WhenDHW(ifused)callsforheat,sequence above
is bypassed.
3. Circulator energizes. If limit circuit is closed, the inducer
starts.After pressureswitchprovesproper airow, control
module initiates 10-second prepurge.
4. Control module sparks the pilot and opens pilot valve in
main gas valve.
a. If pilot does not light within 15 seconds, pilot valve
  isclosedandsparkgeneratoristurnedoff.Control
module initiates a 15-second postpurge, then starts a
new cycle.
b. If pilot does light and control module senses flame
current, spark generator is turned off and main valve
opens.
5. Duringmainburneroperation:
 a. Controlmodulemonitorspilotamecurrent.Ifsignal
is lost, main valve closes, spark generator activates and
sequence returns to step 4.
b. If power is interrupted, control system shuts off pilot
and main gas valves and restarts at step 1 when power
is restored.
6. In the event the
limit control shuts down the boiler — The
control module closes the pilot and main gas valves, but keeps
the inducer operating for 15-second postpurge.
This boiler is equipped with a control system that automatically adjusts a time delay period to turn on the boiler
during a call for heat. This is accomplished by circulating available hot water in the system while measuring water
boiler water temperature changes. The control calculates a suitable delay based on temperature measurements
and turns the boiler on only after it determines that the demand for heat cannot be satisfied with the available hot
water.
Duetothewidevarietyofcontrolsusedinboilerinstallations,thiscontrolisalsoequippedwithanadjustment
forthecalculatedtimedelayperiod(ECONOMYADJUST).IntheMINposition,thetimedelayiszeroandthe
IMPORTANTnoticebelowmustbeobserved:
IMPORTANT
InaccordancewithSection325(f)(3)oftheEnergyPolicyandConservationAct,thisboilerisequippedwith
a feature that saves energy by reducing the boiler water temperature as the heating load decreases. This feature
is equipped with an override which is provided primarily to permit the use of an external energy management
system that serves the same function.
THISOVERRIDEMUSTNOTBEUSEDUNLESSATLEASTONEOFTHEFOLLOWINGCONDITIONSISTRUE:
• Anexternalenergymanagementsystemisinstalledthatreducestheboilerwatertemperatureastheheatingload
decreases.
• Thisboilerispartofamodularormultipleboilersystemhavingatotalinputof300,000BTU/hrorgreater.
• This boiler is equipped with a tankless coil.