New Yorker AP-U AP-110U-N, Installation, Operating And Service Instructions

26

110839-01 - 8/20

AP-U

Installation & Service Manual

iii.

  Limited Recycle:

This feature limits the 

number of recycle trials (for each call 

for heat) to a maximum of three trials.  If 

the flame is lost three times and does 

not successfully satisfy a call for heat, 

the 7505 locks out.

iv.

  Limited Reset (Restricted Mode):

In 

order to limit the accumulation of 

unburned oil in the combustion area, 

the control can only be reset three 

times.  The reset count returns to zero 

each time a call for heat is successfully 

completed.

v.

T-T Jumper:  Select models have 

pre-installed T-T jumper.  

DO NOT

remove jumper.

Note:

DO NOT

 remove “T-T” jumper 

unless

wiring diagram indicates a direct 

connection from thermostat and/or 

tankless heater aquastat control to the 

oil burner primary control’s “T-T” 

terminal.  Refer to appropriate wiring 

diagram, see Figure 5-1.

vi.

Diagnostic LED:  The indicator light on 

oil primary control provides lockout, 

recycle and cad cell indications as 

follows:

 • 

Flashing at 1 Hz (½ second on, ½  

   second off):  system is locked out or  

   in Restricted Mode.

 •

 Flashing at ¼ Hz (2 seconds on, 2  

   seconds off):  control is in Recycle  

   Mode.

 • 

On:  cad cell is sensing flame.

 • 

Off:  cad cell is not sensing flame.

vii.  

Cad Cell Resistance Check

:  

For proper  

 operation it is important that the cad  

 cell resistance is below 1600 ohms.    

 During a normal call for heat, the cad   

 cell leads can be unplugged from the  

 control and the resistance measured  

 with a meter in the conventional way.

Conduct these tests with flame present, 

see chart below.

Flame Detection Range
Normal (0 - 1600 ohms)
Limited (1600 ohms to lockout)

3.  CHECK OIL PRIMARY CONTROL

CAUTION

Due to the potential hazard of line voltage, 

only a trained, experienced service technician 

should perform the following safety checks. 

      This control contains no field-serviceable parts.  

DO NOT attempt to take it apart.  Replace entire 

control if operation is not as described.

a.

Preliminary Steps

  •  

Check wiring connections and power  

     supply.

  •  

Make sure power is on to the controls.

  •  

Make sure limit control is closed.

  •  

Check contacts between ignitor and the  

     electrodes.

  •  

Check the oil pump pressure.

  •  

Check the piping to the oil tank.

  •  

Check the oil nozzle, oil supply and oil  

     filter.

b.  Check Safety Features
  Safe Start:

 •

  Place a jumper across cad cell terminals.

 •

  Follow procedure to turn on burner.   

    Burner must not start, indicator light turns  

    on and control remains in Idle Mode.

 •

  Remove jumper.

c.  Simulate Ignition or Flame Failure:

  •  

Follow procedure to turn on burner.

•  

Check cad cell resistance.  If resistance  

     is below 1600 OHMS and burner runs  

     beyond safety cut-out time, cad cell is  

     good.

•

   If safety switch shuts down burner and 

       resistance is above 1600 OHMS, open  

     line switch to boiler.  Access cad cell  

     under ignitor, clean face of cad cell and  

     see that cell is securely in socket. Check   

     gasket around perimeter of ignitor lid for  

     proper seal.  If gasket is missing or  

     damaged, replace gasket.    

          Room light can effect cad cell           

      resistance. Reset safety switch. 

  •  

Close line switch to boiler.  If burner  

     starts and runs beyond safety switch  

     cut-off time, cell is good.  If not, install  

     new cell.

  •  

Close hand valve in oil supply line.

7

 System Start-Up 

(continued)

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