Rapid Engineering CGTH-30, Installation & Operation Manual

Page: 48 / 64

CGTH I
NSTALLATION
, O
PERATION AND
S
ERVICE
M
ANUAL
42 of 55
2. When the motor approaches nominal r u nning
speed, the press u re s w itch closes and acti v ates
the ignition mod u le w hich in t u rn initiates the
p u rge.
3. The ignition mod u le then energizes the spark
igniter.
4. When sparking b egins, the gas v al v e is ener-
gized.
5. If a flame is detected, the gas v al v e remains
open. When the call for heat is satisfied, the sys-
tem control mechanism de-energizes and the
gas
v al v e is t u rned off.
6. If no flame is detected, the gas v al v e is closed,
and a p u rge period b egins. After the p u rge
period, the ignition mod u le energizes the spark
igniter and the gas v al v e. If a flame is still not
esta b lished, a third and final p u rge/ignition
seq u ence is b eg u n. After three failed attempts,
the system control mechanism w ill lock o u t for a
period of one ho u r or u ntil the u nit is reset.
7. Reset is accomplished b y remo v ing po w er from
the heater for at least fi v e seconds.
8. With a three-try mod u le, w hen the flame is
esta b lished and then lost on the first or second
trial, the gas v al v e w ill a u tomatically t u rn off. A
p u rge and trial for ignition w ill then occ u r.
12.4 Testin g
Esta b lish that a satisfactorily p u rged gas s u pply and
an electrical s u pply is a v aila b le to the heater.
With the gas s u pply t u rned off at the gas v al v e, and
the electrical s u pply isolated b y s w itching off at the
local s w itch and remo v ing the appliance electrical
pl u g, open the control cham b er sec u red b y the fo u r
scre w s. Remo v e the sealing scre w from the o u tlet
press u re tap w ith a 3/16" Hex Key Allen Wrench and
install a test tap and hose. Remo v e the co v er cap
from the reg u lator scre w w ith a straight slot scre w -
dri v er thro u gh the top hole of the bu rner. See Page
42, Figure 37 .
T u rn on appliance gas v al v e and connect appliance
electrical pl u g. Ens u re that the timer or thermostat, if
fitted, is set to call for heat. S w itch on po w er at the
local s w itch. If necessary, the seq u ence as descri b ed
a b o v e, in the first and second paragraphs, sho u ld
take place. If not, refer to detailed fa u lt finding
seq u ence. When flame is esta b lished, check the gas
press u re reading and adj u st if necessary. See data
la b el or Page 10 , Section 2, for req u ired gas press u re
setting.
Check the gas press u re at the o u tlet of the gas v al v e
to ens u re minim u m press u re. See Page 10, Section
4 , for req u ired gas press u re settings.
S w itch off the electrical s u pply (sh u tting do w n the
heater), remo v e press u re ga u ge and refit pl u g at o u t-
let press u re tap, ens u ring a tight gas seal. Replace
cap and reg u lator scre w . Close bu rner side co v er.
FIGURE 37: Pressure Testin g
Out le t Pre ssu re T ap
C o v er Cap and
R e g u la t o r S c rew