Patterson-Kelley MOD-04 owner manual Test of Ignition Safety System, Test of Low Water Cut-off

Models: MOD-04

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Modu-Fire®Gas-Fired Boiler

Installation

 

 

 

 

 

 

2.Gas connection has been made, pressure tested for leakage, and the line purged of air. Make sure all required bleeds and vents have been in- stalled.

3.Water connections are complete, and the boiler and system have been filled and purged of air.

4.The boiler must be connected to a 120 volt / 60 Hz power source with proper polarity and dedi- cated machinery ground. Provide a disconnect having adequate overload protection.

5.Combustion air openings are not obstructed in any way and have adequate capacity. (See Sec- tion 3.5)

6.The boiler is placed the proper distance from any combustible walls or substances, in accor- dance with Section 3.3.3.

7.Relief valves have been properly piped to floor drains.

3.11SAFETY CHECKS

The following checks of safety systems must be made before putting the boiler into normal opera- tion.

Before firing the boiler refer to Sections 4.1 and 4.2 for information on the use of the controls, lighting, and shut-down procedures.

WARNING!

Never attempt to operate a boiler that has failed to pass all the safety checks described below.

WARNING!

After checking controls by manual adjustment, make sure they are always reset to their proper settings.

3.11.1 Test of Ignition Safety System

Test the ignition system safety shutoff as follows:

1.Close the gas cock which is downstream from the two safety shut off valves (in the vertical line).

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 trans- former and pilot will operate. Both functions will be indicated by separate indicator 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 "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 an- other 10 - 15 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 pro- grammer will assume a “Flame Failure” and go to a "lockout" mode. Lockout will require man- ual 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

The boiler is furnished with a flow-switch-type low water cutoff in the outlet nozzle. Test as follows:

Operation of the switch can be checked by first turn- ing the boiler off and then turning the system pump off, stopping water flow in the system. After turn- ing off the pump, turn the boiler back on. It should not operate, and a red indicator for "Low Water" or "Water Flow" should be illuminated. Do not shut the pump off while the boiler is operating.

Perform appropriate tests on any external probe-type low water cutoff.

3.11.3 Test of Limit Controls

Fire the boiler and test the high limit control as fol- lows:

With the main burner operating, turn down the tem- perature setting on the "high-limit" thermostat until

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Patterson-Kelley MOD-04 owner manual Test of Ignition Safety System, Test of Low Water Cut-off, Test of Limit Controls