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DEFINITION OF DELAYS (SEE FIG. 8)
DBF
(Delay Before Feed)
HAW
(Hold After Water OK)
Water Feeding Period
Programming EWF
Three DIP style switch blocks program the EWF operation mode.
FIG.9
(a):Delay Before Feed Mode
S1
OFF
OFF
ON
FF
1
2
3
4
5
6
7
8
Factory settings (shown above):
•
MODE = LWCO
•
DBF = 2 minutes
•
Excess Feed = Disabled
•
FF = 1 Gallon
•
HAW = 0 delay
See Fig. 2 for location of the programming switches.
If programming the EWF to operate in Fixed Feed Mode, be
sure to follow the procedure "Testing and Setting Fixed Feed
Systems" before putting the system into service.
The amount of time before the
EWF starts feeding once a low
water condition has been detected
by the low water cutoff.
The amount of time before the
EWF stops feeding after a normal
water condition has been detected
by the low water cutoff. This delay
allows the EWF to feed additional
water to the boiler after the LWCO
is satisfied, and it is only available
when the EWF is in LWCO mode.
Use this setting when a water level
higher than that set by the LWCO
is required or if the LWCO does
not have an appropriate delay on
make, (DOM), feature.
The amount of time that the EWF
feeds the boiler. The EWF feeds 1
gallon each minute**.
(b):Excess Feed Mode
ON
OFF
LWCO
MODE
1
2
0.5 Min.
3
1 Min.
2 Mins.
4
4 Mins.
5
6 Mins.
8 Mins.
10 Mins.
If all DBF switches are set to OFF, DBF delay is zero.
If all FF switches are set to OFF, the system will automatically feed 1 gallon.
If all HAW switches are set to OFF, HAW delay is zero.
If multiple switches are ON for DBF, Excess Feed, FF, or HAW, the lowest setting will be used.
** The EWF will feed 1 gpm for inlet pressures of 20
to 120 PSI as long as the inlet/outlet pressure
differential is at least 20 PSI. (For example, with a
boiler pressure of 15 PSI, the inlet pressure of the
EWF should be at least 35 PSI.) When pressures fall
outside this range, test the system and set the
EWF operating controls to compensate for your
application.
FIG. 8
Low Water
Condition
Normal Water
Condition
Delay Before Feeding
Period (DBF)
Feed Valve
Open
Feed Valve
Closed
S4
OFF
ON
ON
6 Gals.
8 Gals.
10 Gals.
12 Gals.
15 Gals.
R
N
t e
B I
R
R
t a
n i
g
E
M
B
H
*
(
G
U
p
o t
9
0
9
0
1 -
2
0
1
2
0
1 -
5
0
1
5
0
1 -
8
5
1
8
5
&
H
g i
h
r e
(5)
Low Water Period
Hold Period After
Water OK, (HAW)
Water Feeding Period
(c):Fixed Feed and Hold
After Water OK Mode
S3
OFF
OFF
ON
1
2
3
4
5
6
7
8
*MBH is thousands of BTU's
e
c c
o
m
e
n
d
e
d
per hour
c x
e
s s
F
e
e
d
**Excess feed settings are
S
e
t t
n i
g
based upon normal boiler
a
/ s l
M
o
t n
) h
* *
operation throughout typical
heating seasons. These
6
G
a
. s l
recommended settings do not
8
G
a
. s l
account for water added due
to boiler maintenance.
1
0
G
a
. s l
Follow boiler manufacturers'
usage recommendations if
1
2
G
a
. s l
they differ from the settings
1
5
G
a
. s l
shown here.
ON
1 Gal.
2 Gals.
3 Gals.
4 Gals.
5 Gals.
0.5 Min.
1 Min.
2 Mins.
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