Laars Mascot II, Installation And Operation Instructions Manual

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Mascot II Boilers and Water Heaters
Page 37
installation of this kit. The installation is not proper
and complete until the operation of the converted
appliance is checked as specified in the
manufacturer's instruction supplied with the kit.
AVERTISSEMENT
Ce conversion doit être installé par un organisme de
service conformément aux instructions du fabricant et
tous les codes et les exigences de l'autorité
compétente. Si les informations contenues dans ces
instructions n'est pas suivi à la lettre, un incendie,
une explosion ou de la production de monoxyde de
carbone mais résultat causant des dommages
matériels, des blessures ou des pertes de vie. Le
service est responsable pour la bonne et complète
l'installation de ce kit. L'installation n'est pas correcte
et complète jusqu'à ce que le fonctionnement de
l'appareil converti est vérifiée comme spécifié dans le
manuel d'instruction fourni avec le kit.
Conversion to/from LP Gas Instructions:
1. Install "Propane Gas" sticker over the "Natural
Gas" sticker where the gas supply line enters the
appliance (or vice versa).
2. Fill out gas conversion sticker and install adjacent
to the Rating Plate sticker behind the center door
panel.
3. Confirm that the gas supply is propane (natural
gas).
4. Start boiler per lighting procedure shown on inside
front cover or side of appliance.
WARNING
Serious injury or death could occur if
CO
2
levels are not adjusted properly.
5. With a combustion analyzer, check CO
2
and CO
levels at both maximum and minimum input. Input
rating will remain unchanged.
6. Remove lower cover to access gas valve and adjust
as needed. Begin by adjusting the maximum input
CO
2
then continue by adjusting the minimum
input CO
2
. Any high fire adjustment may affect
low fire settings. Screws for adjustment are shown
in
Figure 26.
7. Reinstall front cover.
SECTION 12.
Trouble Shooting
12.1 Sequence of Operation
Mascot II is a cold start appliance that should start
only on a call for heat from a tank aquastat, room
thermostat, zone valve end switch or other space
temperature control device (flow switch for DHW).
1.
Upon a call for heat: (a) the internal pump and
system pump will start; (b) the blower will begin a
short pre-purge.
2. Following the prepurge cycle the direct spark
ignition will spark and will begin a 4 second trial
for ignition. The unit is allowed one or three
ignition retries.
3. The gas valve will then be energized and a reduced
rate ignition will occur. The unit will remain in a
reduced rate start-up period for several seconds.
4. After the reduced rate start time is over, the unit
will be in normal operation. Firing rate will
modulate based on the heating load via the
temperature controller settings and readings.
5. When the call for heat is complete, or the unit reaches
its setpoint temperature, the gas valve will close, and
the fan will continue to run for its post-purge. If a
pump delay time is used, the pump will continue to
run for the specified amount of time (adjustable from
0.1 to 10 minutes).
12.2 Short Cycling
Because Mascot II is a modulating boiler, and its
input will decrease when there is a reduction in heating
load, short cycling is greatly reduced. If the heating load
drops below the minimum input of the boiler for an
extended period, the boiler will have a tendency to short
cycle. This can be a symptom of improper control or
piping layout. When in DHW mode under low load
conditions, the boiler will normally cycle more often,
but should not cycle frequently during call for central
heating.
12.3 Error Codes -
See Table 14 .
Figure 26. Adjustment Screws.