Rapid Engineering CTHN-40, Руководство по установке и эксплуатации

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SECTION 17: O
PERATION AND
M
AINTENANCE
73 of 91
17.2.2 To Start Heater - Unitary
T u rn gas valve and electric po w er OFF and w ait five
min u tes for u nb u rned gases to vent from heater.
T u rn ON main gas valve.
T u rn ON electric po w er.
Set thermostat to desired temperat u re. B u rner
sho u ld light a u tomatically.
Once the heater is operating, keep a w ay from heater.
Do not to u ch any part of the heater beca u se it is very
hot.
17.3 Multiburner System Operation
17.3.1 Checking the Electrical System
1. Set all thermostats belo w room temperat u re.
2. T u rn on po w er s u pply to the system controls.
3. Check to see that no part of the system (i.e.
b u rners, p u mp, o u tside air s u pply blo w er) is
po w ered.
4. Individ u ally check each zone by energizing the
thermostats separately. Each zone thermostat
sho
u ld start the p u mp immediately. When the
p u mp reaches the nominal r u nning RPM, the
press u re s w itch closes and activates the ignition
mod u le. A pre-p u rge period w ill precede b u rner
ignition trial.
5. If more than one system is installed, be s u re that
no part of one system is affected by the controls
of a different system.
6. Make a preliminary vac uu m check at b u rners in
branches w hich have an adj u stable damper
co u pling. See Page 74, Figure 35 for vac uu m
meas u ring instr u ctions. This check is to ens u re
that all dampers are open before the system is
fired. The vac
uu m meas u red in the b u rner
control ho u sing sho u ld be more than .75" w c.
17.3.2 Starting the System - Multiburner
Note: D u ring the initial firing, the protective oil on the
t u be may smoke for 30 to 60 min u tes and adeq u ate
ventilation sho u ld be provided.
1. Start w ith all thermostats belo w room
temperat u re.
2. Open main gas valve.
3. T u rn u p thermostats one at a time, w aiting to
see that all b u rners in a zone start. When the
b u rner ignites, a bl u e flame w ill be observed
thro u gh the vie w er w indo w .
4. If any abnormal operation occ u rs, see Page 78,
Section 18.1 .
17.3.3 Se q uence of Operation - Multiburner
1. Thermostat, on a call for heat, signals the
control panel or relay contacts to energize the
p
u mp motor. The p u mp (and o u tside air s u pply
blo w er, if u sed) are activated.
2. When the p u mp motor achieves normal r u nning
RPM, the press u re s w itch at the p u mp inlet
closes.
3. After a minim u m 45-60 second pre-p u rge delay
(system control only), the zone relay
corresponding to the thermostat calling for heat
is energized (system control only), and line
voltage is directed to the b
u rners in the zone.
4. When s u fficient vac uu m differential ( see Page
74, Section 17.3.6 ) is available at the b u rner and
the control system is s u pplying line voltage to
the b u rner, the press u re s w itch w ithin the b u rner
closes and energizes the ignition mod u le.
5. After a 45 second pre-p u rge, the ignition mod u le
opens the gas valve and energizes the
electrode. When the flame is established, the
sparking seq
u ence ends.
6. If the flame is not established d u ring the ignition
seq u ence, the ignition mod u le closes the gas
valve and p u rge begins. The ignition mod u le w ill
try 2 additional times for ignition ( w ith p u rge
bet w een). If ignition is not established, the
mod u le w ill lock-o u t.
NOTE: After 1 ho u r, the mod u le w ill reset
a u tomatically and ret u rn to steps 5 and 6.
7. If a flame is detected, the gas valve remains
open. When the call for heat is satisfied, the
system control or relay de-energizes the b
u rner
and p u mp po w er s u pply. When u sing the system
control, the p u mp t u rns off after a post-p u rge
period.
8. If the flame exting u ishes d u ring operation, the
ignition mod u le w ill attempt to re-establish the
flame. If ignition is not re-established, the
mod
u le w ill lock-o u t.