Check Oil Primary Control; Cad Cell Resistance When Sensing Flame; Cad Cell Location - Burnham MPO Installation & Service Instructions Manual

3-pass oil boilet
Hide thumbs Also See for MPO:
Table of Contents

Advertisement

To reset from Restricted Mode: Press and
hold the reset button for 30 seconds.
When the LED fl ashes twice, the device
has reset.
v.
T-T Jumper: Select models have pre-
installed T-T jumper resistor. To remove
jumper, if applicable, use side-cutting pliers
to cut jumper (See Figure 28).
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 fl ame.
Off: cad cell is not sensing fl ame.
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, once the control has
entered the Run Mode, press and release the
reset button. Indicator light will fl ash 1 to 4
fl ashes. See Table 7 for equivalent cad cell
resistance.
TABLE 7: CAD CELL RESISTANCE WHEN
SENSING FLAME
F
a l
s
h
e
s
C
a
d
C
1
L
e
s s
h t
a
n
4
0
2
M
o
e r
h t
a
n
4
0
3
M
o
e r
h t
a
n
8
0
4
M
o
e r
h t
a
n
1
6
b. CHECK OIL PRIMARY CONTROL
C
A
D
u
e
o t
h t
e
p
o
e t
n
i t
v
l o
a t
g
, e
o
n
y l
a
t
a r
s
e
v r
c i
e
e t
c
h
n
c i
a i
n
f
l o
o l
w
n i
g
s
a
e f
y t
c
h
T
h
s i
c
o
n
r t
l o
c
o
n
a t
p
a
t r
. s
D
o
n
t o
t a
e t
R
e
p
a l
c
e
e
n
i t
e r
c
o
n
a
s
d
e
s
r c
b i
e
. d
i.
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.
40
l l e
R
e
s
s i
a t
c n
e
n i
o
h
m
s
0
0
a
n
d
e l
s s
h t
a
n
8
0
0
0
a
n
d
e l
s s
h t
a
n
1
6
0
0
0
0
a
n
d
e l
s s
h t
a
n
5
0
0
0
U
I T
O
N
l a
h
a
z
a
d r
o
l f
n i
e
n i
e
, d
e
x
p
r e
e i
n
c
e
d
s
h
o
u
d l
p
e
f r
r o
m
h t
e
e
c
k
. s
n i
s
n
o
f
e i
d l
s -
e
v r
c i
e
a
b
m
t p
o t
a t
k
e
t i
a
p
a
. t r
r t
l o
f i
o
p
r e
t a
o i
n
s i
n
t o
e l
Check the oil pump pressure.
Check the piping to the oil tank.
Check the oil nozzle, oil supply and oil
fi lter.
ii. 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.
iii. Simulate Ignition or Flame Failure:
Follow procedure to turn on burner.
Close hand valve in oil supply line.
Failure occurs, device enters Recycle
Mode. Indicator light fl ashes at ¼ Hz rate
2 seconds on, 2 seconds off).
Device tries to restart system after
approximately 60 seconds.
After third Recycle Mode trial, safety
switch locks out within safety switch
timing indicated on label and control
enters Restricted Mode. Indicator light
fl ashes at 1 Hz rate (½ second on, ½
second off). Ignition and motor stop and
oil valves closes.
To reset from Restricted Mode: Press and
hold the reset button for 30 seconds.
When the LED fl ashes twice, the device
has reset.
iv. Cad Cell Check: See Figure 29.
Figure 29: Cad Cell Location
Perform cad cell resistance check as
outlined in control feature. 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

Hide quick links:

Advertisement

Table of Contents
loading

This manual is also suitable for:

Mpo84Mpo147Mpo189Mpo231

Table of Contents