Patterson-Kelley THERMIFIC MODU-FIRE, Supplement Manual

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Modu-Fire
®
Gas-Fired Boiler Installation
2. With the main gas cock (inlet manual gas valve)
open and the pilot gas cock open, the burner
should be cycled on. After all the safety limits
on gas pressure, water flow and temperature are
satisfied, the blower will run and pre-purge the
boiler.
3. When air flow is established, the ignition
transformer and pilot will operate. Both
functions will be indicated by separate green
lights on the flame safeguard.
4. If a satisfactory pilot is established, the spark
will terminate and the pilot will remain on,
alone, for 10 seconds.
5. After 10 seconds, the green "Main” light on the
flame safeguard will go on; gas will not flow
since the downstream cock is closed. The
"Pilot" will remain on, along with the "Main
Gas", for another 10 seconds and then go out.
Since the gas cock is closed, at this point there
will be no main flame signal and the flame
safeguard programmer will assume a “Flame
Failure” and go to a "lockout" mode. Lockout
will require manual reset of the flame safeguard.
After completing this test, turn off the boiler and
reopen the downstream gas cock.
3.11.2 Test of Low Water Cut-off
(Refer To TBIG Latest Edition)
3.11.3 Test of High-Limit Control
Fire the boiler and test the high limit control as
follows:
With the main burner operating, turn down the
temperature setting on the "high-limit" thermostat
until the main burner shuts off. The high-limit
switch must be manually reset after testing. This
check should also be made for the "Operating
Temperature" control (the green "Heat" indicator
will go out) (see next section for Modulating Units).
Readjust thermostats to desired operating
temperature and set high-limit temperature, typically
20º F above operating temperature.
3.11.4 Test of Gas Pressure Switch
(Refer To TBIG Latest Edition)
3.12 I
NITIAL
A
DJUSTMENTS
3.12.1A – Configuring the Controller
Operating Modes:
Internal Setpoint
Night Setback
Outdoor Air Reset
Analog Input Setpoint (See Section 3.12.1B.)
Analog Input Direct Drive (Multiple boiler
Controls)
Definitions:
SP1 - Setpoint 1: ...................This is the primary
setpoint of the boiler.
SP2 - Setpoint 2 : ...................An alternate setpoint.
Available through the
night setback contact.
dSP - Differential Setpoint : ..An alternate setpoint
differential from SP1.
Available through the
night setback contact.
tA - Air temperature: ............Measurement of
outside air
temperature.
SP.E - External Setpoint: .......Measurement of the
external setpoint.
HyS1: ....................................Low temperature
differential.
HyS3: ....................................High temperature
differential.
Internal Setpoint
The boiler water outlet temperature is controlled to
SP1 (setpoint 1) and the boiler modulates to
maintain SP1 subject to the upper and lower
temperature differentials and the upper and lower
setpoint limit.
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