TT-S
ERIES
I
NSTALLATION
, O
PERATION
AND
S
ERVICE
M
ANUAL
90 of 198
FIGURE 76:
8
.3LS Remote Panel RMTC
20.2.4 DDC - Ready Option
The DDC-ready option pro
v
ides inp
u
ts to recei
v
e
control signals from a c
u
stomer determined control
system and o
u
tp
u
ts to pro
v
ide seq
u
ence stat
u
s to the
same. A 24VAC transformer is pro
v
ided
b
y Weather-
Rite's control panel for
u
se
b
y the c
u
stomer's DDC
system to command "Unit Start" and "Heat Start"
signals (
b
y means of DDC dry contact)
b
ack to the
air handler control panel.
The air handler pro
v
ides 24VAC signals to the
c
u
stomer's DDC for monitoring the follo
w
ing stat
u
s:
Unit R
u
nning
Heat R
u
nning (Gas Val
v
es "On")
Flame Fail
u
re
On all air handlers, the
bu
rner mod
u
lation
w
ill
b
e
controlled 0-10VDC or 4-20MA signal from the
c
u
stomer's DDC. Temperat
u
re monitoring and
mod
u
lation
v
al
v
e adj
u
stment are completed
b
y the
c
u
stomer s
u
pplied control system. For
v
ol
u
matic
recirc
u
lating and
v
ol
u
matic
w
/VFD style air handlers,
the control system can also control the mod
u
lating
dampers.
20.3 Basic Se
q
uence of Operation
The follo
w
ing is an o
v
er
v
ie
w
of the seq
u
ence of
operation. Depending on the application and options
s
u
pplied
w
ith the air handler, this can
v
ary greatly.
Thoro
u
ghly re
v
ie
w
all doc
u
mentation for the air
handler, incl
u
ding the electrical print, to familiarize
and
u
nderstand the act
u
al seq
u
ence of operation.
Summer (Blower Only)
With po
w
er s
u
pplied to the air handler and the
S
u
mmer/Off/Winter s
w
itch on the remote panel in the
SUMMER position, po
w
er is s
u
pplied to the
b
lo
w
er
motor starter coil, allo
w
ing the
b
lo
w
er motor to start.
The
bu
rner circ
u
it is NOT energized.
Winter (Blower & Burner)
With po
w
er s
u
pplied to the air handler and the
S
u
mmer/Off/Winter s
w
itch on the remote panel in the
WINTER position, po
w
er is s
u
pplied to the
b
lo
w
er
motor starter coil, allo
w
ing the
b
lo
w
er motor to start.
A
u
xiliary contacts on the
b
lo
w
er starter close,
po
w
ering the flame relay thro
u
gh the high limit, and
lo
w
- and high-gas press
u
re s
w
itches (if pro
v
ided).
When airflo
w
is pro
v
en
b
y the
bu
rner airflo
w
s
w
itches, the
bu
rner firing circ
u
it is po
w
ered
u
p. After
the pilot flame or main flame is pro
v
en
b
y the flame
detector, the main and
b
locking
v
al
v
es are opened
and the ignition transformer is de-energized. The
temperat
u
re control system is po
w
ered separately
and controls the flo
w
of the f
u
el to maintain space /
discharge set point temperat
u
re thro
u
gh the
temperat
u
re control amplifier
w
hich controls the
mod
u
lating
v
al
v
e.
20.4 Flame Control
The main f
u
nction of a flame safeg
u
ard de
v
ice is to
pre
v
ent the flo
w
of f
u
el into the
bu
rner in the e
v
ent of
either a flame fail
u
re d
u
ring a r
u
nning cycle or an
ignition fail
u
re d
u
ring an attempt to fire. The
secondary f
u
nction of a flame safeg
u
ard is to cycle
the entire
bu
rner system. Flame safeg
u
ards are
u
sed
w
ith rectification type flame detectors,
w
hich pro
v
ide
a small p
u
lsating direct c
u
rrent
w
hen a s
u
ita
b
le flame
is present. The c
u
rrent is amplified and
u
sed in the
electronic net
w
ork of the flame safeg
u
ard. If the
flame rod signal is ins
u
fficient to hold in the electronic
net
w
ork, the flame safeg
u
ard de
v
ice q
u
ickly and
safely sh
u
ts do
w
n the
bu
rner system. It also triggers
the LED for alarm and the remote alarm light.
Three types of flame safeg
u
ard de
v
ices are
u
sed on
this eq
u
ipment. They are the Fireye
®
MicroM, Fireye
®
M4RT1 and the Honey
w
ell
®
RM7897. The Fireye
®
MicroM and the Honey
w
ell
®
RM7897 are
v
ersatile in
that it can
b
e co
u
pled to a UV Scanner detector or a
flame rod style detector. Its constr
u
ction is mod
u
lar,
so that
b
y changing amplifiers and programmers its
f
u
nction is
v
aried. The Fireye
®
M4RT1 is similar,
bu
t
only accepts flame rod detectors and its f
u
nctions are
controlled
b
y the remo
v
al or installation of j
u
mpers.
All three flame safeg
u
ards can
b
e
u
sed in all agency
Summary of Contents for TT Series
Page 2: ......
Page 4: ......
Page 136: ...TT SERIES INSTALLATION OPERATION AND SERVICE MANUAL 130 of 198 FIGURE 114 Regulator RV61 ...
Page 167: ...SECTION27 TROUBLESHOOTING 161 of 198 ...
Page 175: ...SECTION27 TROUBLESHOOTING 169 of 198 ...
Page 177: ...SECTION27 TROUBLESHOOTING 171 of 198 ...
Page 198: ...TT SERIES INSTALLATION OPERATION AND SERVICE MANUAL 192 of 198 ...
Page 202: ...TT SERIES INSTALLATION OPERATION AND SERVICE MANUAL 196 of 198 ...
Page 203: ...SECTION 28 THE WEATHER RITE TT SERIES WARRANTY 197 of 198 ...
Page 204: ...TT SERIES INSTALLATION OPERATION AND SERVICE MANUAL 198 of 198 ...