Dunkirk D249 Series Commercial Boiler - Manual (Page 5)

WATER LEVEL
29” TO FLOOR
Steam Side Control - Two low water cutoff devices and
two pressuretrols, one with auto reset and the second with
manual reset, are required. In order to make the two
low water cutoff devices work in the appropriate
sequence, manufacture recommends locating both
devices at same end of boiler.
There are three different control systems for three different
types of condensate returns.
Identify the three different types of condensate returns:
• Gravity return - condensate is returned by gravity.
• Condensate pump return - condensate is returned
by pump(s), controlled by the water level in the
condensate receiver tank.
• Boiler Feed Pump Return - condensate is returned by
pump(s), controlled by the water level in the boiler.
Normal
Water Line
STEAM SIDE CONTROLS
Figure 2 - Steam Boiler Feed Pump Return
Figure 3 - Steam Gravity and Condensate Pump Return
Gravity Return And Condensate Pump Return
With gravity and condensate pump return, additional
control components are the same. See Table #5a and
Figure #2 for tappings.
• Tappings B & B location shown in Figure #2.
Installation shown in Figure #3, Primary LWCO and
Pressuretrol with gauge glass set.
• Tappings D or F (Figure #2)- Manual reset pressuretrol
and ¼” 90° brass syphon.
• Tappings E & F - Secondary LWCO (w/manual reset).
Use in conjunction with primary LWCO equipped on
boiler.
When using two LWCOs, place manual reset lower than
automatic LWCO. Water must be visible in gauge glass
when manual reset trips.
• Figure 3 shows how to raise automatic (Series 67)
LWCO 1-inch.
• Remove 1” from long side of ¼” diameter 90° brass
siphon tube.
• Remove nipple in series 67 and replace with 1 ½” long
nipple and street elbow.
• Water level control device located on condensate
receiver tank and controls condensate return pump is
not supplied.
Table #5a: CSD-1 Steam Trim Carton Material List for Gravity Return
or Condensate Pump Return (Part No. 41257103)
Item Description Part No. Qty.
1 LWCO w/Manual Reset (secondary) 240007388 1
2 Bushing, Steel or Cast 1” x 1¼” 14657016 1
3 Pressure Switch Control, Manual Reset 14662311 1
4 90° Brass Syphon, ¼” 14643004 1
5 ELB,ST,1/2”,45 DEG.BRASS 240007541 1
6 NIPPLE 1/2” X 1/2”LG BRASS 240007542 1
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