Pentair MT - Manual (Page 10)

Page 10 Pentair Water Commercial Pool and Spa
3A-3. Hi-Limit Checkout
After running the boiler for a long enough period
to bring the water temperature within the range of the
hi-limit, slowly back off the high limit setting until the
unit shuts off. The main burners should re-ignite when
the hi-limit is turned back up to its original setting.
The high limit should now be reset and the boiler
run until it shuts off automatically on high limit.
Now that all tests of the safety shutoff devices
have been completed, refer to Section 3B for the
proper settings of temperature controls.
NOTE: Should any of the controls fail to
function properly, consult the factory or your gas
company representative.
3B. To Start Up System
(See Section 3A for Initial Start Up)
Start up boiler:
1. Be certain system pump is running.
2. Lighting instructions are provided on the rating
plate and in the User’s Manual and are as
follows:
a. Turn off main electrical switch.
b. Turn off all manual gas valves and wait
five minutes.
c. Set aquastat or thermostat to lowest setting.
d. Turn manual pilot valve to "ON." For
standing pilot system, press on pilot relay
knob, light pilot and keep relay knob
depressed for one minute then release.
Once the pilot is lit, the power will be
supplied to the gas valve(s) upon activation
of the aquastat.
e. Slowly turn manual gas valve to "ON."
f. Reset all safety switches (manual reset high
limit, low water cutoff, etc.).
g. Turn on main electric switch.
h. Set temperature controller (aquastat) to
desired temperature. Pilot will light
automatically (intermittent ignition pilot
system) and ignite main burners whenever
the aquastat calls for heat.
i. Adjust the pool aquastat as follows:
When the pool water has reached the desired
temperature, as measured with an accurate
thermometer, decrease the aquastat setting with a
small screwdriver until the boiler shuts off. The pool
boiler will maintain the existing pool water
temperature automatically.
3C. To Turn Off Boiler
1. Turn off main electrical switch.
2. Close all manual gas valves.
3D. Spring and Fall Operation
When the pool is not going to be used for a long
period of time, turn the aquastat down to
approximately 70
o F. This will prevent the pool and
surrounding ground from becoming chilled, save on
fuel costs, and also permit the pool water temperature
to be raised back to swimming temperature in a
shorter period of time.
The pool water temperature should not be
maintained below 70 o F. Colder water will cause
condensation to form on the heat exchanger when the
boiler does fire. Prolonged operation at a lower
temperature will cause the boiler to foul externally.
See “Improper Use of Boiler.”
3E. Winter Operation
To shut down the boiler for longer periods, turn
both the manual gas valve and pilot gas valve to OFF.
Where the danger of freezing does not exist, the
normal filter cycle should be continued all year long to
circulate water through the system even when the
boiler is turned off or shut down completely.
3E-1. Draining Boiler Before Freezing
If the boiler is located where it will be exposed
to freezing temperatures, it should be drained before
the first frost. Drain the boiler by removing the drain
plug on the bottom of the front header casting. Leave
the plug out until time to use the boiler again. The
boiler must be level for proper drainage. If
compressed air is used to blow out the lines, it is still
necessary to follow the same procedure. Keeping the
pool heated by continuously running the boiler may
not be adequate protection due to the possibility of a
pump or power failure.
3E-2. Improper Use of the Boiler
The Model MT pool boiler is not designed for
continuous use as an anti freezing device for pools.
Operating the boiler at water temperatures below
70 o F will cause the heat exchanger fins to be partially
blocked with condensation, resulting in incomplete
combustion. Prolonged operation under these
conditions will result in sooting of the heat exchanger
which can seriously damage the boiler and cause a fire
hazard.