Glossary - Lochinvar GAS HEATER FOR COMMERICAL POOL Installation And Service Manual

Commercial Pool Heaters

GLOSSARY

POWER SUPPLY
120VAC/60Hz/1PH power connects to black (line) and white
(neutral) wires located within an electrical wiring box located
on the left side of the pool heater. A green chassis grounding
wire is also provided for connection to earth ground.
ON/OFF ROCKER SWITCH
The black line voltage wire runs directly to a single pole, single
throw On/Off rocker switch located behind the front cover
accessible by a knurled knob. Turning ON the rocker switch
delivers line voltage to the low voltage transformer and
ignition module.
Note: The On/Off switch does not provide for disconnection
of power being supplied to any remotely connected devices
that may be connected to the pool heater (i.e. pumps, louvers,
power venters, etc.). As such, it may be necessary to locate
and turn "OFF" power to these items before attempting to
service the pool heater.
LOW VOLTAGE SUPPLY TRANSFORMER
A 120VAC to 24VAC transformer located within the control
panel provides 24VAC/60Hz to many of the components
located on the pool heater. One of its 24VAC outputs (blue) is
connected to a circuit breaker and the other (yellow) is
connected to chassis ground.
24VAC CIRCUIT BREAKER
A circuit breaker is provided for protection of the low voltage
supply transformer from overloads and short circuits. The
breaker is located inside the pool heater on the right rear of the
control panel. Power from this breaker goes to the temperature
controller, ignition module and various other components
and/or options on the pool heater. When tripped, all factory-
installed 24VAC components will lose their 24VAC power.
MANUAL RESET HIGH-LIMIT THERMOSTAT
A manual reset high limit thermostat is provided as backup for
the auto reset high limit. This is an adjustable dial, bulb-
capillary style thermostat that will trip and require resetting
should water temperature exceed its settings. When tripped,
all controls remain powered, but 24VAC is prevented from
being delivered to the ignition module's thermostat input.
EMS/SEQUENCER/REMOTE AQUASTAT
TERMINALS
The EMS/sequencer/remote aquastat terminals are provided
for connection of the pool heater to an external energy
management system or sequencer and are located along the top
edge of the terminal strip located within the electrical wiring
box. In addition to providing a means to externally fire the
pool heater, these terminals also provide for remote shutdown
by routing through dry contacts from external devices.
Connection of the external dry contacts to these terminals
requires the removal of one or more factory-installed jumpers
located on the terminal strip.
SAFETY DEVICE TERMINALS
The safety device terminals ensure that no power can be
delivered to the ignition module unless factory/field-installed
safety devices such as flow switches and gas pressure switches
are closed. These safety device terminals are located below
the EMS/Sequencer/Remote Aquastat terminals located within
the electrical wiring box.
offered: Continuous terminals provide for connection of safety
devices that are desired to be constantly monitored.
Intermittent terminals are provided for devices that are only
monitored during a "call for heat" cycle. Connection to either
of these terminals requires the removal of a factory-installed
jumper located on the terminal strip.
TEMPERATURE CONTROLLER
(Operator) A single-stage temperature controller is provided on
the pool heater and it serves to maintain a user selectable
temperature set point. In addition to maintaining a set point, it
can provide for desired differential setting. Ultimately, the
temperature controller delivers 24VAC to the ignition module
and pressure switch when it senses heat mode is desired.
IGNITION MODULE
(Controlled by Temperature Controller)
One ignition module is provided on the pool heater. Upon
sensing the 24VAC delivered to it by the temperature
controller, the ignition module checks for a shorted pressure
switch and then, provided the air switch isn't shorted, supplies
120VAC to its blower output relay and waits for a pressure
switch signal.
BLOWERS
(Controlled by Ignition Module and Relay Board)
Two blowers serve to provide combustion air to the pool
heater. Both blowers operate in tandem anytime the ignition
module is given a call for heat signal.
PRESSURE SWITCH
(Activated by Blower Turning On)
One pressure switch is provided to monitor its On/Off
operation. Upon a call for heat, 24VAC is delivered to the
pressure switch. If the blower generates adequate air pressure,
the pressure switch closes to deliver 24VAC to the ignition
module's pressure switch monitoring input terminal.
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Two types of connections are