Install Instructions

Table 8 Reservoir pipe sizing
Table 9 Boiler feed/condensate return system sizing
Condensate return
Modern steam boilers are designed to steam for less time than
older, larger boilers. When replacing an older steam boiler the
system condensate return time may be longer than the steaming
time. This could cause the following problems:
1. Boilers fitted with an automatic water feed could overfill.
2. Units fitted with only a low water cutoff would shut down
and cycle while waiting for condensate to return.
Following is a simple method for determining whether or not a
reservoir pipe is required to lengthen steaming time for a resi-
dential installation:
1. Disconnect condensate return line at existing boiler.
2. Heat
boiler and allow to steam for 10 minutes. Turn off boiler.
3. Measure length of time from when boiler started to steam to
when condensate begins to return through condensate line.
4. Measure length of time from when condensate begins to
return to when it stops returning. Divide this time by 2.
5. Add time measured in step 3 to time calculated in step 4. This
sum is the average time required for condensate to return to
the boiler.
6. If this total time is 10 minutes or less, no reservoir pipe is
needed.
If total time for condensate to return to boiler (from step 5) is
more than 10 minutes, a reservoir pipe (or boiler feed system) is
recommended. See Table 8 and Figure 20 for suggested reservoir
pipe size. Install as shown in Figure 20.
For larger systems (as noted in Table 8), use a boiler feed system
with a condensate tank and feed pump. You will have to install a
low water cutoff/pump control on the boiler to operate the pump.
Use Table 9 to size boiler feed systems. See Figure 5, page 10, for
tapping locations. (The use of a combination condensate tank and
float-controlled condensate return pump is not recommended.)
For most residential installations a reservoir pipe may be all that
is necessary to ensure proper operation.
Figure 20 Recommended piping for parallel-flow systems
with optional reservoir pipe
Boiler
model
number
Max. boiler
gross
output
Time from initial steaming to average condensate
return (boiler steaming capacity based on 970 Btu per
pound of steam)
15 minutes 20 minutes 30 minutes
MBH
gallons
pipe
length
(feet)
gallons
pipe
length
(feet)
gallons
pipe
length
(feet)
EG/PEG-30,-35 75
¾
¾
1½
1½
3
2½
EG/PEG-40,-45 125
1¼
1¼
2½
2¼
Use boiler feed
system
EG/PEG-50 150
1½
1½
3
2½
EG/PEG-55
175 1¾
1¾
Use boiler feed system
EG/PEG-65
225 2½
2
EG-75
250 2½
2¼
EGH-85
300 3
2½
EGH-95 up
Not recommended — Use boiler feed system if needed
Designed full capacity steaming time of modern boilers is 10 minutes.
Boiler
Model
Gross
Output
Pounds
Steam
Per
Hour
Gallons
Conden-
sate
Per Hour
Minimum Condensate
Receiver Capacity (Gal.)
Recom-
mended
Maximum
Minutes of boiler
operation:
Feed
Pump
Capacity
GPM *
15 30 45 60
EG/PEG-30 62 8 2 4 6 8 0.2
EG/PEG-35 83 10 3 6 9 12 0.3
EG/PEG-40 104 12 4 7 11 14 0.4
EG/PEG-45 125 15 5 9 14 18 0.5
EG/PEG-50 145 17 5 10 15 20 0.6
EG/PEG-55 167 20 6 12 18 24 0.7
EG/PEG-65 209 24 7 14 22 29 0.8
EG-75 240 29 9 17 26 35 1.0
EGH-85 280 34 10 20 31 41 1.1
EGH-95 320 38 11 23 34 46 1.3
EGH-105 360 43 13 26 39 52 1.4
EGH-115 400 48 14 29 43 58 1.6
EGH-125 440 53 16 32 48 64 1.8
*
If pump capacity exceeds capacity shown, pump can be
throttled with globe or ball valve.
Connect piping – steam boilers (continued)
Part Number 550-110-639/0512
19
EG
•
PEG
•
EGH Gas-firEd boilErs — sEriEs 4 — boilEr manual