Weather-Rite TT Series, Инструкция по установке, эксплуатации и обслуживанию

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SECTION 27: T
ROUBLESHOOTING
159 of 198
Burner (continued)
27.4 Temperature Controls
If temperat u re control pro b lems occ u r and are not
remedied in the tro ub leshooting proced u re, refer to
the tro ub le shooting ta b le for the u nit specific
temperat u re control amplifier.
1. For u nits w ith the Maxitrol series 14 tempera-
t u re controls, refer to the Field Ser v ice Check
List for Series 14. Series 14 are s u pplied on
u nits eq u ipped w ith DAT and DATRO style
remote panels.
2. For u nits w ith the Maxitrol series 44 tempera-
t u re controls, refer to the Field Ser v ice Check
List for Series 44. Series 44 are s u pplied on
u nits eq u ipped w ith RMTC remote panels.
3. For u nits w ith the Maxitrol series 94 tempera-
t u re controls, refer to the Field Ser v ice Check
List for Series 94. Series 94 are s u pplied on
u nits eq u ipped w ith WRP style remote panels.
4. For u nits w ith the Maxitrol series MP tempera-
t u re controls, refer to the Field Ser v ice Check
List for Series MP. Series MP are s u pplied on
u nits eq u ipped w ith WRP remote panels.
If pro b lems persist after performing the
tro ub leshooting proced u re and the temperat u re
control tro ub leshooting proced u re contact the factory.
27.5 Series 14 - Preliminary Circuit Analysis
For ease in tro ub leshooting, it is ad v isa b le to w ire the
system as follo w s (this differs from the normal
connection).
• The Discharge Air Sensor is disconnected and
replaced w ith a 10,000 ohm, 1/2 w att test resistor
(terminals 3 and 4). If inlet air sensor is b eing
u sed, disconnect and replace w ith a j u mper. On
u nits w here the Remote Temperat u re Selector is
located a considera b le distance from the heater, it
may b e ad v antageo u s to connect the selector at
the heater location.
1. Connect a DC v olt meter (capa b le of reading 0-
24 V DC) on the Mod u lator or Mod u lator-Reg u -
lator Val v e terminals. Set the temperat u re to
the minim u m dial setting. The DC v oltage
sho u ld read 0 v olts. The DC v oltage sho u ld
grad u ally increase to at least 20 v olts as yo u
slo w ly rotate the dial to the maxim u m dial set-
ting. If these v oltages are o b tained, the v al v e
f u nction can no w b e checked o u t.
2. The operation of the Val v e w ith regard to v olt-
age is as follo w s: from 0 v olts to approximately
5 v olts, the mod u lating v al v e sho u ld b e on
b ypass flo w w ith the heater operating on lo w or
minim u m fire. From approximately 5 v olts to 15
v olts DC, the v al v e sho u ld b e performing its
mod u lating f u nction, and the heater sho u ld b e
firing at a mod u lated flo w rate b et w een lo w and
high fire, depending u pon the v oltage. A b o v e
approximately 15 v olts DC, the Val v e sho u ld b e
deli v ering f u ll flo w to the heater and the u nit
sho u ld b e on f u ll fire. If the DC v oltage is
o b tained on the Val v e terminals, bu t the heater
does not respond as descri b ed, the pro b lem
can b e isolated to the v al v e itself or to the gas
control manifold of the heater.
3. In the e v ent proper v oltages are o b tained, and
the Val v e responds correctly to these DC v olt-
ages, the pro b lem co u ld w ell b e in the w iring
leading to the Discharge Air Sensor or the Dis-
charge Air Sensor itself.
4. If the proper v oltages are not o b tained w hen
w ired as instr u cted, the pro b lem can b e iso-
lated to the electronics and this may once
again
b e re v ie w ed in the check list.
PROBLEM POSSIBLE CAUSE SOLUTION
No main flame Man u al sh u t off v al v e closed Open man u al sh u t off v al v e
Safety Sh u t Off Val v e not operating. Is there
positi v e gas press u re do w nstream of SSOV?
Check w iring from bu rner control to
SSOV
Verify inlet gas press
u re
Replace SSOV
Minim u m gas s u pply press u re Verify minim u m gas s u pply press u re as
per data plate is a v aila b le
B u rner openings o b str u cted Remo v e o b str u ction
Clean bu rner orifice holes
Improper bu rner lo w fire adj u stment on mod u -
lating v al v e
Adj u st lo w fire as per the rele v ant Max-
itrol temperat u re control instr u ctions.