LAARS Pennant PNCV - Install and Operating Manual User Manual

Page 28

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LAARS Heating Systems

Page 28

SECTION 6.

Operating Instructions

6.1 Filling the Boiler System

1. Ensure the system is fully connected. Close all

bleeding devices and open make-up water valve.

Allow system to fill slowly.

2. If make-up water pump is employed, adjust

pressure switch on pumping system to provide

a minimum of 12 psi (81.8 kPa) at the highest

point in the heating loop.

3. If a water pressure regulator is provided on the

make-up water line, adjust the pressure regulator

to provide at least 12 psi (81.8 kPa) at the highest

point in the heating loop.

4. Open bleeding devices on all radiation units

at the high points in the piping throughout

the system, unless automatic air bleeders are

provided at such points.

5. Run system circulating pump for a minimum of

30 minutes with the boiler shut off.

6. Open all strainers in the circulating system,

check flow switch operation, and check for

debris. If debris is present, clean out to ensure

proper circulation.

7. Recheck all air bleeders as described in Step 4.

8. Check liquid level in expansion tank. With the

system full of water and under normal operating

pressure, the level of water in the expansion tank

should not exceed ¼ of the total, with the balance

filled with air.

9. Start up boiler according to the procedure in this

manual. Operate the entire system, including the

pump, boiler, and radiation units for one (1) hour.

10. Recheck the water level in the expansion tank. If

the water level exceeds ¼ of the volume of the

expansion tank, open the tank drain, and drain to

that level.

11. Shut down the entire system and vent all

radiation units and high points in the system

piping, as described in Step 4.

12. Close make-up water valve and check strainer in

pressure reducing valve for sediment or debris

from the make-up water line. Reopen make-up

water valve.

13. Check gauge for correct water pressure and also

check water level in the system. If the height

indicated above the boiler insures that water is at

the highest point in the circulating loop, then the

system is ready for operation.

14. Refer to local codes and the make-up water

valve manufacturer’s instructions as to whether

the make-up water valve should be left open or

closed.

15. After placing the unit in operation, the ignition

system safety shutoff device must be tested. First,

shut off the manual gas valve, and call the unit

for heat. After the pre-purge and ignitor heat-up

time, the main gas terminals will be energized,

attempting to light, for four (4) seconds, and then

will de-energize. The unit will go into lockout

mode. Second, turn the power off and then on

again, open the manual gas valve and allow the

unit to light. While the unit is operating, close the

manual gas valve and ensure that power to the

main gas valve has been cut.

16. Within three (3) days of start-up, recheck all air

bleeders and the expansion tank as described in

Steps 4 and 8 above.

Important: The installer is responsible for identifying

to the owner/operator the location of all emergency

shutoff devices.

WARNING

Do not use this appliance if any part has been

under water. Immediately call a qualified service

technician to inspect the appliance and to replace

any part of the control system and any gas control

that may have been under water.

AVERTISSEMENT

N’utilisez pas cet appareil si l’une de ses pièces est

passée sous l’eau. Appelez tout de suite un techni-

cien en entretien et en réparation pour inspection

de l’appareil et remplacement des pièces du sys-

tème de commande, et des pièces de commande

du circuit gaz, qui sont passées sous l’eau.

6.2 Sequence of Operation

The amber “Ready” light on the front panel

indicates that the control system is energized. Upon a

call for heat from the system temperature sensor, the

green “Heat” indicator on the front panel will light.

The green “Pump” indicator on the front panel will

light.

Once the water flow switch makes, and if all of

the safety interlocks are closed, the ignition module(s)

will energize the blower(s) for a 15-second pre-purge,

followed by a 20-second period to allow the ignitor(s)

to heat.

Energizing the blower pressurizes the air box

(which supplies air to the burners) and closes the

normally-open contact(s) of the airflow pressure

switch(es). This allows the ignition module to proceed

with the ignition sequence.

The blocked flue pressure switch senses the

pressure difference between the exhaust plenum and

the blower inlet plenum. It will interrupt the airflow

sensing circuit if this pressure exceeds a maximum

value. If airflow is not proven, the ignition module

will either attempt ignition again (up to three times) or

will lockout (if the optional lockout ignition module is

used).

The ignition module checks that the ignitor

current has reached a minimum value and energizes

the gas valves at the end of the ignitor-heating period.

The green indicators on the front panel will

light, indicating that the gas valves are open. After a

4-second trial for ignition, the ignitor switches off, and

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