Laars Lite 2 LC Installation And Operation Manual - page 8
Page 6
Install a check valve if there is any chance of
"back-siphoning" when the pump stops. Do not install
any other valve or variable restriction in the piping
between the heater outlet and the pool, unless it is
being used as a diverter valve.
2G. Pressure Relief Valve
A pressure relief valve is not supplied with the
heater, but local plumbing codes may require it. To
install a pressure relief valve, replace the 3/4" brass
plug on top of the input/output header with the valve
(see Fig. 10). The valve setting should be at or below
the maximum working pressure of any component in
the filter system
2H. Pressure Switch
The pressure switch is preset at the factory for
normal pool installations. Do not adjust the pressure
switch unless any of the following conditions exist:
1.
If the top of the heater is 900 mm or more below
the surface of the pool.
2.
If any part of the filter system piping is 900 mm
or more above the top of the heater jacket.
If either of these conditions exist, follow the
instructions in Section 2J.
NOTE: Do not make the pressure switch adjustment if
the heater is installed more than 4.6 m below or 1.8 m
above the pool surface. Consult Waterpik Technolo-
gies for recommendations.
On some installations, the piping from the heater
to the pool is very short. The back pressure could be
too low to trigger the pressure switch. If this happens,
it may be necessary to install a directional fitting, or
elbows where the return line enters the pool. This will
increase back pressure enough for the heater to operate
properly.
2J. Pressure Switch Adjustment
The pool filter must be clean before making this
adjustment. The heater does not have to be firing.
1.
Turn the rotary switch to OFF, and make sure the
pressure switch is at its lowest setting. This is
done by rotating the adjuster counter clockwise as
far as it will go (see Fig. 11).
2.
Start the filter pump and confirm by means of
hearing an audible click or with an ohmmeter that
the pressure switch closes. If the switch fails to
close, replace it with a switch that has a lower
minimum setting.
3.
Turn the adjuster clockwise to open the contacts
(see Fig. 11).
4.
With the pump still running, reduce the pressure
setting 7 to 14 kPa psi to reclose the contact.
5.
Turn off the pump and make sure the pressure
switch contacts open. The contact must open
right away when the pump shuts off.
It may be necessary to repeat these steps to get a
proper setting. The switch must be set so that the
heater will not fire unless the pump is running. If a
proper setting cannot be reached, contact the factory
service department.
Elevated spas are a special problem if the water
surface is more than 2.4 m above the heater, because
the pressure switch has a limit of 35 kPa. A special
pressure switch is available from the factory for these
installation.
When the water surface is more than a few feet
below the heater, use a pressure switch with a mini-
mum setting of 7 kPa.
2K. Automatic Chlorinators
(Chemical Feeders)
A high concentration of chlorine (or other chemi-
cal) in the pool heater can be very destructive. Heater
damage caused by chemical concentration is not
covered by the Waterpik Technologies warranty. See
Section 3F for recommended levels.
Figure 8. Piping Connections