LAARS Mighty Stack MS-080 (Sizes 199, 300, 399) - Install and Operating Manual - Manual (Page 23)

Mighty Stack Page 23
SECTION 7.
Maintenance
7.1 System Maintenance
1. Lubricate the system water-circulating pump, if
required, per the instructions on the pump.
2. If a strainer is employed in a pressure reducing
valve or the piping, clean it every six months.
3. Inspect the venting system for obstruction or
leakage at least once a year. Periodically clean
the screens in the vent terminal and combustion
air terminal (when used).
4. Keep the appliance area clear and free from
combustible materials, gasoline, and other
flammable vapors and liquids.
5. If the appliance is not going to be used for
extended periods in locations where freezing
normally occurs, it should be isolated from the
system and completely drained of all water. All
systems connected to it should also be drained or
protected from freezing.
6. Low water cutoffs, if installed, should be
checked every 6 months. Float type low water
cutoff should be flushed periodically.
7. Inspect flue passages, and clean with brushes/
vacuums, if necessary. Sooting in flue passages
indicates improper combustion. Determine the
cause and correct.
8. Inspect the vent system and air intake system,
and if the vent system is Category III, ensure
that all joints are sealed properly. If joints need
to be resealed, follow venting manufacturer's
instructions to clean and reseal vent system.
7.2 Appliance Maintenance and
Component Description
Only genuine Laars replacement parts should be used.
Caution
Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and
dangerous operation. Verify proper operation after
servicing.
Attention
Lors d’entretien ou de réparation des commandes,
étiquetez tous les câbles avant de les déconnecter.
Des erreurs de câblage peuvent provoquer des
fonctionnements incorrects et dangereux. Après
toute intervention d’entretien ou de réparation,
vérifier que l’appareil fonctionne correctement.
The gas and electric controls on the appliance
are engineered for long life and dependable operation,
but the safety of the equipment depends on their
proper functioning. It is strongly recommended that
a qualified service technician inspect the basic items
listed below every year.
a. Ignition control
b. Ignitor
c. Water temperature control
d. Automatic gas valve
e. Pressure switches and tubing
f. Blower
g. High limit
h. Pump
i. Relays
j. Flow switch
k. Gas train
l. Control components
7.2.1 Burners
Close main manual gas valve before proceeding.
Checking the burners for debris - Remove the ignitor/
burner access panel and ignitor, and inspect the
burners through the ignitor hole using a flashlight to
illuminate. If there is any indication of debris on the
burners that is visible, all the burners will need to be
inspected more thoroughly. Remove the gas manifold
assemblies and the burner assemblies. Inspect the
burners. Clean burners, if necessary, by blowing
compressed air from the outside of the burners into
the center of the burner. A dirty burner may be an
indication of improper combustion or dirty combustion
air. Determine the cause, and correct. Replace the
burners in the reverse order.
7.2.2 Filter
The filter used in the Mighty Stack is washable
and has an 80% arrestance rating. Since the filter is
washable, it will only need replacement occasionally.
If filter replacement is needed, it should only be
replaced with a factory part. Inspect the air filter
monthly, or more often in dirty environments. If there
is debris on the air filter, remove it from the filter
frame, and wash it with mild soap and water. Ensure
that the filter is completely dry before reinstalling.
7.2.3 Gas Valve
The gas valve is designed to operate with supply
pressures of 4-13 in. w.c. (1.0 to 3.2 kPa).
To remove a valve, shut off 120-volt power
and the manual gas shutoff valve. Remove the front
panels from the unit. Disconnect the wires to the valve.
Disengage the unions before and after the valve, and
remove the valve. Pull the pipe nipples from the inlet
and outlet of the valve, and clean the threads on the
pipe nipples for reuse. Apply new tape or pipe dope
to the pipe nipples (threaded joints should be coated
with piping compound resistant to action of liquefied
petroleum gas), and reinstall in reverse order. Turn
on manual gas shutoff valve and 120 volt power and
check appliance operation and tightness of gas valve
connections.