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110891-02 - 5/22
RSAH
Installation & Service Manual
A. Setting the High Limit: The high limit is factory set
at 190oF. To adjust, turn the HI TEMP Dial A until
the desired setting is displayed. (Setting
range: 100o-220oF).
B. Setting the Low Limit: The low limit is designed
to maintain temperature in boilers equipped with
tankless coils used for domestic hot water. The
low limit is factory set to OFF. Prior to adjusting,
remove the jumper (not equipped on all units)
B. Then turn the LP TEMP Dial C clockwise until
the desired temperature is displayed. For proper
operation, the low temperature limit setting should
be least 10o below the high limit setting. NOTE:
For cold start operation, the low limit must be
turned OFF. IMPORTANT: If low limit temperature
cannot be set above 140oF, remove jumper B.
(Setting range: OFF or 110o -200o F).
C. Setting the Economy Feature: The Economy
Feature is factory set for a 1 zone heating system.
To adjust, turn the ECONOMY Dial D until the
number displayed equals the number of heating
zones. Do not include indirect water heaters in the
number of heating zones. The Economy Feature
conserves fuel by reducing boiler temperature
(see “How Thermal Targeting Works”. If the
heating system is unable to supply needed heat
to the house, the ECONOMY Dial should be
turned to a lower setting (example: In a three zone
house, turn the dial to 2 or 1.) Conversely, if the
boiler provides adequate heat, added fuel savings
can be achieved by selecting a higher setting
(example: 4 or 5). If the heating and indirect water
heater signals were not separated when wiring the
control, the Economy Feature should be turned
OFF to ensure the boiler supplies adequate
temperature to heat the indirect tank.
D. Setting the Zone/Indirect Switch: See WIRING.
Setting
Off
Disables economy function. Will allow boiler to fire until hi-limit temp is reached
and re-fire with a 10
o
subtractive differential
LO
Provides lowest level of fuel savings. Use this setting only if the house does not
stay warm at higher settings.
1
Recommended setting for single zone systems
2
Recommended setting for Two zone systems
3
Recommended setting for Three zone systems
4
Recommended setting for Four zone systems
5
Recommended setting for Five zone systems
HI
Provides highest level of fuel savings
E. Optional Features
:
NOTE: The Program Mode -
Pro - is accessed by turning the LO TEMP dial to
a position just above OFF.
1.
Thermal Pre-Purge: Thermal Pre-Purge
is designed to maximize boiler
efficiency. When activated, the control
will supply latent heat that may remain
in the boiler from a previous run cycle
to the heating zone that is now calling. The
control monitors how quickly the boiler
temperature is declining and activates the
burner only when it determines that the latent
heat is insufficient to satisfy the call. During
the purge cycle, the display will indicate
Pur. This feature works with single-zone
and multi-zone heating systems utilizing
circulators or zone valves. No change in
wiring is needed.
To activate Thermal Pre-Purge
1. Turn the LO TEMP dial to access the
Program Mode - indicated in the display as
Pro
2. Turn the HI TEMP dial to select feature 1
3. Push the Test/Setting Button to turn Thermal
Pre-Purge ON or OFF
4. Reset LO TEMP and HI TEMP settings to
desired temperatures.
2. Degrees Fahrenheit or Celsius: The
control has the ability to operate in
degrees Fahrenheit or Celsius. When
operating in Celsius, a c will appear in
the display next to the temperature when
ever the temperature is below 100
degrees.
To change between degrees Fahrenheit and degrees
Celsius
1. Turn the LO TEMP dial to access the Program
Mode - indicated in the display as Pro
2. Turn the HI TEMP dial to select feature 2
3. Push the Test/Setting Button to c for Celsius or F for
Fahrenheit
4. Reset LO TEMP and HI TEMP settings to desired
temperatures.
3.
Manual Reset Low Water Cut-Off:
The low water cut-off operation on the
HydroStat can be set to operate in automatic
(default) or manual reset mode. When in
manual reset mode, the control will shut-down
the burner immediately when low water
condition is detected. If the low water
condition is sustained for 30 seconds, the low
water light will blink,indicating that the
control has locked out the burner. The
control can only be reset by pushing the Test
Settings button on the top of the control. The
manual reset feature meets CSD-1 code
requirements.
IMPORTANT:
The system must be checked by a
qualified heating professional prior to resuming
operation.
WARNING: DO NOT ADD WATER UNTIL THE
8
Operating
