Install Instructions

28
110503-01 - 4/20
CL Installation & Service Manual
A. HydroStat 3250 PLUS SEQUENCE OF
OPERATION
IMPORTANT This boiler is equipped with
a feature that saves energy by reducing the
boiler water temperature as the heating load
decreases.
This feature is equipped with an override which is
provided primarily to prevent the use of an external
energy management system that serves the same
function. THIS OVERRIDE MUST NOT BE USED
UNLESS AT LEAST ONE OF THE FOLLOWING
CONDITIONS IS TRUE:
• An external energy management system is installed
that reduces the boiler water temperature as the
heating load decreases.
• This boiler is not used for any space heating.
• This boiler is part of a modular or multiple boiler
system having a total input of 300.000 BTU.HR or
greater.
• This boiler is equipped with a tankless coil.
1. Setting the Control
a. Setting the High Limit: The high limit is
factory set at 190F. To adjust, turn the
HI TEMP Dial A until the desired setting
is displayed. (Setting range: 100-220F).
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 10 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 140F, remove jumper B. (Setting range: OFF or
110 -200 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”.
10 Operating
If the heating system is unable to
supply needed heat to the house,
the ECONOMY Dial should be turned
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 re until hi-limit temp is reached
and re-re with a 10 subtractive di󰀨erential
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 LP
TEMP dial to position just above Off.
2. 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
• Turn the LO TEMP dial to access the
Program Mode - indicated in the display as
Pro.
• Turn the HI TEMP dial to select feature 1.
• Push the Test/Setting Button to turn Thermal
Pre-Purge ON or OFF.
• Reset LO TEMP and HI TEMP settings to
desired temperatures.