Heat Link 31360, Руководство пользователя

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HeatLink
®
Mixing Valve Reset Control Stk# 31360
®
Link Heat
www.heatlinkgroup.com
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Boiler Operation (European Version)
Boiler Sensor on the Supply (Boiler Sensor DIP switch = Supply)
The boiler sensor can be located on the boiler supply if the Stk# 31360 is the only control that is operating the boiler.
When in the supply mode, the Stk# 31360 determines the required operating temperature of the boiler using Boiler
Load Reset. With Boiler Load Reset, the Stk# 31360 operates the boiler at the lowest possible supply temperature
that is sufficient to satisfy the requirements of the mixing valve. If this mode of operation is selected, the boiler pump
should either operate continuously, or be operated in parallel with the system pump contact (Sys Pmp).
Note: The boiler pump should not be operated by the boiler’s aquastat, as this may lead
to improper cycling of the boiler because of inconsistent flow past the boiler supply sensor.
Boiler supply
sensor
Boiler Differential (BOIL DIFF)
An on / off heat source such as a boiler must be operated with a differential in
order to prevent short cycling. When the boiler supply temperature drops below
the bottom rail of the differential, the Stk# 31360 closes the Boiler contact to
fire the boiler. When the boiler supply temperature rises above the top rail of
the differential, the Stk# 31360 opens the Boiler contact to turn off the boiler.
With the Stk# 31360, either a fixed or automatic differential setting is selected. If
automatic differential (Ad) is selected, the Stk# 31360 automatically adjusts the
boiler differential under the current load conditions to avoid short cycling.
Supply W
ater
Temperature
Time
Differential = 10 F (5 C)
165 F(74 C)
B
oile
r o
ff
B
oi
le
r o
n
155 F (68 C)
160 F (71 C)
B
oile
r o
ff
B
oi
le
ro
n
Boiler Sensor on the Return (Boiler Sensor DIP switch = Return)
The boiler sensor should be located on the boiler return if the Stk# 31360 is one of many controls that can call for
boiler operation. When in the return mode, the Stk# 31360 provides a boiler enable as described in the BOILER
ENABLE section. The Stk# 31360 no longer tries to control the boiler supply water temperature directly but allows
the boiler to operate at its operating aquastat setting when required. If this mode of operation is selected, the boiler
pump should either operate continuously, or be operated in parallel with the system pump contact (Sys Pmp).
Note: The boiler pump should not be operated by the boiler’s aquastat, as this may lead to improper cycling
of the boiler because of inconsistent flow past the boiler return sensor.
Boiler return
sensor
No Boiler Sensor
The Stk# 31360 is capable of operating without a boiler sensor if desired. Without a boiler sensor, the Stk# 31360
provides a boiler enable as described in the BOILER ENABLE section, but is unable to provide boiler protection.
This type of application is typical if the Stk# 31360 is drawing heat from a heat source that already incorporates
some form of boiler protection.
No boiler
sensor
Boiler Enable (30% Enable / 10% Enable)
The Stk# 31360 has a DIP switch that allows for the selection between a 30% boiler enable and a 10% boiler enable. This switch is only functional
when the Boiler Sensor DIP switch is set to Return.
In the 30% position, the Stk# 31360 closes the Boiler contact when the position of the mixing valve exceeds 30%. The Boiler contact remains
closed until the position of the mixing valve reduces below 15%. This setting would normally be chosen for low mass boilers (copper fin-tube,
etc.), or systems with low thermal mass in the loop between the boiler and the mixing valve.
In the 10% position, the Stk# 31360 closes the Boiler contact when the position of the mixing valve exceeds 10%. The Boiler contact remains
closed until the position of the mixing valve reduces below 5%. This setting is normally chosen for high mass boilers (cast iron, steel fire-tube,
etc.), or systems with large thermal mass in the loop between the boiler and the mixing valve. In order to prevent short cycling, the Boiler contact
has a minimum on time, and a minimum off time.
Refer to Page 4 for a description of boiler protection.
When the Stk# 31360 determines that boiler operation is required, the Boiler contact terminals (7 and 8) close. While the Boiler contact is closed,
the burner segment in the LCD is displayed.
Boiler Minimum (BOIL MIN)
Most boilers require a minimum water temperature in order to prevent flue gas condensation. The BOIL MIN adjustment is set to the boiler
manufacturer’s minimum recommended operating temperature. Only when the boiler temperature is measured by a boiler sensor can the Stk#
31360 provide boiler protection. In this case, when the boiler is firing and the boiler temperature is below the BOIL MIN setting, the Stk# 31360
turns on the MIN segment and reduces the heating load on the boiler by limiting the output of the mixing valve. If the installed boiler is designed
for low temperature operation, set the BOIL MIN adjustment to OFF.
Boiler Operation
European Version