LAARS Pennant PNCV (Sizes 500-2000) - Install and Operating Manual - Manual (Page 46)

LAARS Heating Systems Page 46
6.4.10 External Boiler Operation
When mode 6 is selected, the control allows for
an external control to operate the Pennant’s stages. In
this mode, the control operates the pump in order to
provide purging and exercising. The staging operation
is provided by an external device such as an Energy
Management System (EMS) or External Staging
Control.
Heat Demand – A heat demand is generated
when stage one is wired properly, and the external
control closes the contacts on the stage one terminals
(1C-1NO), calling the Pennant for heat. The Pennant
is shipped with a jumper between the Com D and Ht D
terminals, and this jumper must remain in place when
and external control is providing the heat demand
signal to these terminals. The control energizes the
boiler pump (if equipped), energizes the Pmp-Pmp
terminals, and turns on the boiler pump segment in the
display. The control also turns on stage 1 of the boiler.
Section 5.3 contains important information about
external staging controls and building automation
systems. Other wiring methods may be unsafe. The
wiring in Section 5.3 of this manual must be used.
6.4.11 Limit Controls
In addition to the temperature control, Pennant
appliances are fitted with a manual reset high limit and
an automatic reset high limit. These are located near
the rear of the cabinet on the right side, behind the
slide out drawer (see Figure 32 ). Both controls should
be set at least 25°F higher than the target temperature
to avoid short cycling. To set these controls, remove
the control panel cover and pull the control panel
out to gain access. Appliances with reversed heat
exchangers have the limit controls relocated to the left
side of the appliance. The left access door must be
removed to gain access to the limit controls on these
appliances.
6.4.12 Advanced Programming Mode
Advanced programming mode allows the
installer to set the temperature control for proportional
staging. In advanced programming mode, the
interstage differential, interstage delay, interstage on
and off delay, and minimum time on and off are all set
manually.
NOTE: Advanced programming mode is rarely
required. It is intended for advanced installers,
and only when the application demands such
programming.
To enter advanced programming mode, remove
the bezel on the temperature control by pulling out at
the bottom. Remove the small phillips head screw to
access the dip switch. The dip switch is mounted on a
circuit board.
Locate the letter “A” on the circuit board and
slide the corresponding dip switch toward the letter
“A”. The default setting of this dip switch is toward
the OFF lettering on the circuit board.
6.5 Operating the Burner and Set Up
6.5.1 Set Up for 0 to 2500 Feet Altitude
The Pennant appliance utilizes a modular design
to achieve its stage-firing. The setup must be checked
before the unit is put in operation. Problems such as
failure to start, rough ignition, strong exhaust odors,
etc. can be due to improper setup. Damage to the
Pennant resulting from improper setup is not covered
by the limited warranty.
1. Using this manual, make sure the installation
is complete and fully in compliance with the
instructions.
2. Determine that the appliance and system are
filled with water and all air has been bled from
both. Open all valves.
3. Observe all warnings on the Operating
Instructions label and turn on gas and electrical
power to appliance.
4. Switch on the appliance power switch located on
the right side of the unit.
5. The Pennant will enter the start sequence, as long
as the unit is being called for heat. The blower
and pump come on for pre-purge, then the ignitor
warm-up sequence starts and after the ignitor
warm-up is complete and all safety devices are
verified, the gas valves open. If ignition doesn’t
occur, check that there is proper gas supply.
Wait 5 minutes and start the unit again. During
initial start up, air in the gas line may cause the
Pennant to "lock out" during the first few trials
for ignition. Depending on the ignition modules
installed, the manual reset button on the ignition
modules may need to be depressed to restart the
Pennant.
6. When the unit is running, the supply gas pressure
must be checked. Inlet gas pressure must not
exceed 13" w.c. (3.2kPa). The minimum inlet gas
pressure is 5" w.c. (1.2kPa).
7. Once the inlet gas pressure is verified, the
outlet gas pressure from each valve (manifold
gas pressure) must be checked, and adjusted, if
necessary. The manifold gas pressure must be
2.5" w.c. (0.62kPa).
8. Complete the setup by checking the CO
2
at the
outlet of the unit. The CO
2
should be 8% for
natural gas, or 9.2% for propane.
9. After placing the appliance in operation, the
Burner Safety Shutoff Device must be tested.
To test:
(a) Close gas shutoff valve with burner
operating.
(b) The flame will go out and blower will
continue to run for the post purge cycle.
One additional attempt to light will follow.
Ignition will not occur as the gas is off. The
ignition control will lockout, and will have
to be reset before the unit will operate.