37
IX. OPERATING (continued)
boiler heat rather than cycling the boiler. The
Circulator Pre-purge time has a factory setting of
2 minutes and is field adjustable between 2 and
20 minutes. Refer to Table 9.
e. Start Temperature (
t_
)
The amount of “Heat available” is calculated by
taking the difference between measured boiler
water temperature and the Start Temperature
setting. Useful “Heat Available” is dependent on
the type of heating emitter installed in the home.
Heat emitters require a certain minimum
temperature to operate effectively. Our default
settings reflect cast iron radiators. Fan Coils may
require a start temperature setting of 180°F or
160°F before providing heat to the home. The
Start Temperature has a factory setting of 140°F
and is field adjustable between 140°F and 180°F.
f
.
Priority Time (
Pt_
)
When the Priority Time parameter is set to “on”
and Domestic Hot Water (DHW) call for heat is
“on” the DHW demand will take “Priority” over
home heating demand and the system circulator
will be forced “off”. Priority Time ends and the
system circulator is released to service home
heating demand when Domestic Hot Water call
for heat is over. When Priority Time parameter
is set to “Off” the DHW call for heat does not
force “off” the system circulator. The Priority
Time has a factory setting of “On” and is field
adjustable between “On” and “Off” Refer to
Table 10.
Call for
Heat
ZC
and
ZR
Terminal
Function
(
ZC_
)
Boiler
Temp.
Boiler Status,
(B1 Output)
TT
= on
--
< 140
Start with no delay
TT
= on
--
>140
Start after 2 minute delay
ZR
= on
ZC_
=
ZR
<140
Start with no delay
ZR
= on
ZC_
=
ZR
>140 Start after 2 minute delay
ZR
= on
ZC_
=
DH
<140
Start with no delay
ZR
= on
ZC_
=
DH
>140
Start with no delay
TABLE 9: CIRCULATOR PRE-PURGE TImE EXAmPLE,
PARAmETER PP_= 2 mINUTES
g. ZC and ZR Terminal Function (
ZC_
)
The boiler control allows configuration of the ZC
output functionality to help the LEDV boiler
integrate into each installation more effectively.
The ZC output can be connected to a domestic
hot water circulator or a second heating zone
circulator. These applications are selected as
follows:
i.
When
ZC_
is set equal to Domestic Hot Water
Demand (
dh
)
When there is an Indirect Water Heater (IWH)
the boiler control provides a “ZR” input
terminal for the IWH Aquastat and “ZC”
output terminal for the DHW Circulator.
When there is a DHW call for heat, the
System Circulator is “forced off”, the DHW
Circulator terminal is energized and the
circulator pre-purge time delay control logic
is bypassed to allow the boiler to fire without
delay. When DHW demand ends the System
Circulator “force off” is removed, the
circulator can respond normally, and the
DHW Circulator is de-energized. The DHW
call for heat is detected by a voltage on to the
“ZR” terminal. When a Priority Time
parameter is set to “off” the System Circulator
is not forced off for a DHW call for heat.
Refer to Table 10.
Call for Heat
Circulator Status
T-T
Input
ZR
Input
Priority
Time
(
Pt_
)
System
Circulator
Output
DHW
Circulator
ZC Output
on
off
On
on
off
on
on
On
off
on
off
on
On
off
on
on
off
OFF
on
off
on
on
OFF
on
on
off
on
OFF
off
on
TABLE 10: DOmESTIC HOT WATER DEmAND,
(PARAmETER
ZC_
=
DH
)
Содержание LE DV Series
Страница 5: ...5 I General Information Figure 1A LEDV Packaged Water Boiler with Beckett AFII Burner ...
Страница 6: ...6 I General Information continued Figure 1B LEDV Packaged Water Boiler with Riello BF Burner ...
Страница 19: ...19 v venting continued Figure 11 Vent Installation Figure 12 Vent Connector Un Assembled ...
Страница 20: ...20 v venting continued Figure 13 Vent Connector Assembled Figure 14 Air Intake Installation ...
Страница 48: ...48 xiii Repair Parts continued Figure 29 LEDV Bare Boiler Assembly ...
Страница 50: ...50 xiii Repair Parts continued Figure 30 LEDV Boiler Jacket Insulation ...
Страница 55: ...55 xiii Repair Parts continued Figure 33 Vent Kit Repair Parts ...
Страница 60: ...60 U S Boiler Company Inc P O Box 3020 Lancaster PA 17604 1 888 432 8887 www usboiler net ...
