Model LD Pool and Spa Heater
Page 29
SECTION 10.
Professional Maintenance, Service
and Diagnostic Troubleshooting
WARNING
SERVICING SAFETY
Some of the servicing procedures for the Lite2 model
LD pool heater are hazardous because they involve
fuel gas, high voltage electricity, moving parts and
procedures which require testing or temporary
bypass of safety controls. For this reason, the heater
must be serviced only by a qualified professional
service technician.
IMPROPER SERVICE HAZARD
The Lite2 model LD pool heater incorporates unique
design features. Incorrect service of this heater can
result in personal injury or damage to property. To
avoid such hazards, the heater must be serviced only
by a qualified professional service technician.
AVERTISSEMENT
PRÉCAUTIONS LORS DES RÉPARATIONS ET DE
L’ENTRETIEN
Certaines procédures d’entretien et de réparation des
appareils de chauffage à LD présentent des dangers,
car elles mettent en jeu des gaz combustibles,
l’électricité à haute tension, des pièces mobiles et
des procédures qui nécessitent des mises à l’essai
ou la dérivation temporaire des commandes de
sécurité. Pour cette raison, l’appareil de chauffage
doit être entretenu et réparé uniquement par un
technicien professionnel qualifié.
DANGERS D’UN ENTRETIEN INADÉQUAT
Les appareils de chauffage à LD comportent des
caractéristiques techniques uniques. Une réparation
ou un entretien inadéquat peut entraîner des
blessures corporelles ou des dommages à la
propriété. Pour cette raison, l’appareil de chauffage
doit être entretenu et réparé uniquement par un
technicien professionnel qualifié.
10.1 General Information
A qualified professional technician must service
the Lite2 model LD pool heater using Jandy Pool
Products, Inc.'s service procedures. Before calling for
service, however, the owner should check for obvious
problems. The other components in the pool system,
including pump, filters and strainers, water valves, gas
supply and time clocks have an effect on heater
operation.
Confirm that the LD heater control switch is set
to either "POOL" or "SPA" and that the temperature
control knob is set high enough to make the heater
operate. Make sure the pump is operating, that the
filter and strainers are not clogged, that there are no
mis-positioned water valves, that the gas is not shut off
and that time clocks are properly adjusted. Also be
sure that there is no blockage of the vent or louvers
which supply combustion air to the burners.
10.2 Natural-Draft Combustion System
The Lite2 model LD pool heater has an atmo-
spheric combustion system. This system is illustrated in
Figure 22.
As the heated exhaust gases rise out of the
combustion chamber, flow is created through the
system and fresh combustion air is drawn into the
heater through the louvers cut into the front and sides
of the heater. Gas is forced through an orifice into the
open end of a burner. When the gas flows into the
burner, a “negative” pressure is created at the opening
of the burner. This negative pressure pulls air into the
burner with the gas and mixes the two together. As
the gas/air mixture flows through the burner ports it is
ignited in the combustion chamber. Hot combustion
products then rise through a highly efficient heat
exchanger. Combustion products then enter a flue
collector and are directed to the outdoors through the
grate top of the heater or a vent pipe and cap.
10.3 Heater Components and Their
Operation
1.
Gas Valve / Regulator
- The gas valve controls
gas flow into the manifold. It provides flow only
when the temperature controls require heat and
only if all safety controls enable operation. It is
also a
positive pressure regulator
. It regulates
the gas pressure in the manifold to specifications
addressed earlier in this manual. This is neces-
sary for proper operation of the burner system.
2.
LD Temperature Control
- The Jandy LD
controller is an electronic control which senses
water temperature by means of a thermistor and
controls heater operation to bring the water to the
desired temperature. The desired temperature is
set by rotating a knob on the face of the control
panel. To achieve accurate water temperatures,