Pentair MT - Manual (Page 9)

MegaTherm Commercial Pool Heating Boiler Page 9
pool. If this condition exists, follow this procedure to
adjust the switch:
1. With the boiler on, the filter pump running and
the filter clean, slowly increase the pressure
setting until the boiler shuts off. Slowly decrease
the pressure setting until the boiler comes back
on. Decrease the pressure setting another 2 psi to
complete the switch setting.
2. Test the setting by closing the manual gas valve
and turning off the filter pump. Turn the
thermostat to the high setting and slowly open
the manual gas valve. The boiler should not try
to fire when the filter pump is off.
If the boiler is installed more than three feet
above the pool level, install an eyeball fitting on the
end of the return line to the pool to create adequate
back pressure that the boiler to operate the pressure
flow safety switch. Never reduce the factory setting of
the pressure switch. For special installation problems,
consult the factory.
SECTION 3.
Operation
3A. Initial Start-Up
3A-1. Initial Filter Cycle on a New Pool
On a newly constructed pool, be sure to run the
filter pump long enough to completely "turn-over" the
pool water before turning on the boiler. This will
insure that any dirt and residue from the construction
will be removed. The filter may clog rapidly during
this period, causing the boiler to severely cycle if it
is on.
3A-2. Starting Instructions
1. Check the following installation details before
proceeding:
a. Has the required air supply been provided?
b. Is the boiler properly vented?
2. Be sure the filter is clean.
3. Start the filter pump.
Before placing the boiler in operation, the
automatic safety shutoff devices must be
checked. Once the unit is connected to the gas
piping and after all of the requirements in
Section 2 have been met, follow this procedure:
a. Before beginning the tests, make sure the
main manual gas valve, and any other firing
valves are in the OFF position.
b. Make sure the power switch on the boiler is
in the “ON” position. After placing the
manual pilot valves in the open position, and
resetting all safety devices (high limit,
pressure switch, Low-Water-Cutoff, etc.),
pilots can be lit following the procedure
located on the boiler rating plate.
c. Once the pilots are lit and have been
established for five minutes, the flame
failure response time should be checked as
follows:
System 16: (Electronically supervised
standing pilot system standard on propane
gas). Extinguish the pilot flame by placing
the manual pilot valve in the closed
position, and, at the same time, begin
recording the time it takes for the output
signal from the electronic ignition control
to be interrupted. Refer to the electrical
drawing supplied with the boiler for wiring
details. The signal interruption can be
detected either with a test light or a
voltmeter. Because the ignition controls are
in series, the control just upstream of the
gas valves should be tested first. Under no
circumstances should the response time
exceed 5 seconds.
System 18: (Intermittent ignition supplied
only for natural gas). With this system,
pilots are automatically lit when the
thermostat calls for heat. The pilots are
permitted a trial period for ignition, then
the system is locked out if it fails to light.
To retry ignition, power to the boiler must
be momentarily interrupted. After the pilot
is initially lit, the trial for ignition time
should be checked by turning off pilot gas,
and, at the same time, monitoring the time
it takes for the audible sparking at the pilot
burner to stop. Under no circumstances
should the trial for ignition exceed 15
seconds because electronic ignition controls
are in series. The control just upstream of
the gas valves should be tested first (refer
to the electrical drawing supplied with the
unit).
Once the trial for ignition period has been
checked, the controls should be reset and
the flame failure response time checked
by following the procedure given for
system 16.
4. With the pilots lit, initial activation of the main
burners can be achieved by slowly opening the
main manual valve. The result should be a
smooth lighting of the main burners.