Installation manual
www.desatech.com
118531-01C 21
Blue
V a riable
Fan Switch
Fan Switch
(N.O.)
Green
White
On
1 1 0/115 
V . A.C.
Blower
Motor
Black 
Off
1
2
Black
FIREPLACE INSTALLATION
Continued
3. 
Place  blower  against  lower  rear  wall  of 
rebox  outer  wrapper  with  exhaust  port 
directed upward and thermodisc positioned 
up near the replace bottom. Thermodisc 
must be oriented near replace bottom as 
shown in Figure 30, page 20, in order to 
sense temperature and properly operate. 
Blower will be held in position against back 
wall by magnets incorporated onto blower 
housing (see Figure 30, page 20).
4. Be  certain  that  all  wire  terminals  are 
securely attached to terminals on blower 
motor and thermal switch and that screw 
for thermodisc bracket and green ground 
wire is tight. 
5. Mount speed control box by placing plastic 
control  shaft  through opening  in  switch 
bracket (see Figure 28, page 19).
6.  While supporting speed control, secure 
control  shaft  with  lock  nut  by  pushing 
and turning lock nut with pliers clockwise 
until it is  tight  against  mounting  plate. 
Place  control  knob  provided  on  shaft 
(see Figure 28, page 19).
7. Check  to  make  sure  that  power  cord is 
completely  clear  of  blower  wheel  and 
that there are no other foreign objects in 
blower wheel. Also double check all wire 
leads and make sure wire routing is not 
pinched or in a precarious position. Cor-
rect accordingly. 
8.  Turn  on  power  to  duplex  outlet  if  previ-
ously turned off per warning in column 1, 
page 19.
9. Plug  in  blower  power  cord  to  duplex 
outlet.
10. Blower will only run when speed control 
knob is in the ON position and the thermal 
switch senses temperature after replace 
begins to heat up. The blower speed can 
be adjusted by rotating control knob. To 
turn off, turn knob fully counterclockwise 
until it clicks off. If blower is ON and has 
been  running  with  replace  operating, 
blower will continue to run for a short time 
after  replace  has  been  turned  off. As 
thermal switch cools down, blower shuts 
down automatically.
11. Peel off backing paper and stick supplied 
wiring  diagram  decal  on  rebox  bottom 
approximately 12" in front of blower (see 
Figure 29, page 20). 
WIRING DIAGRAMS
    
   
    -
Figure 31 - Blower Wiring Diagram for 
Thermostat-Controlled Models 
DO NOT
CONNECT
TO 120V
RED
REPLACE FA CTOR
Y
WIRING WITH 105°C
EQUIV A LENT OR
HIGHER RATING
EXTERNAL WIRING
USE ONL Y  CLASS 2
THERMOSTA T  WIRE
18 GA. RED/WHITE
WHITE
TH/TP
TP
TH
WALL SWITCH
THERMOPILE
PILOT
BURNER
IGNITOR
PILOT
GAS
LINE
O
F
F
P
I
L
O
T
O
N
PILOT SAFETY VA L V E
INCOMING
MAIN GAS
SUPPLY
Figure 32 - Millivolt Ignition Wiring 
Diagram










