Weil-McLain 88 Water and steam boilers — Series 2 — for Gas, Light Oil, & Gas/Light Oil-Fired Burners
16 Part No. 550-100-068/0308
Connect steam boiler piping
General steam piping information:
Hartford loop piping arrangement and wet return are required for 1.
steam boilers. Use the Hartford loop for both pumped-return and
gravity-return systems.
Maintain 24-inch minimum from waterline to bottom of header (63" 2.
from bottom of section).
When using condensate receiver, feed pump must be energized by 3.
boiler-mounted pump controller.
Install piping:4.
Install piping as shown on a. page 17 through page 18 for single boil-
ers. See page 19 for additional requirements when piping multiple
boilers.
Return pipe sizing.b.
Pumped return — Size return piping by pump.•
Gravity return — Size gravity return same as Hartford loop •
equalizer pipe size.
Drain valve — Install system drain valve in lowest part of return c.
piping close to boiler. See Figure 17, page 15, for sizing.
Cold water fill piping — Connect cold water fill piping as shown in d.
Figure 20. Also shown are recommended valves and water meter,
if used. Water meter will detect added makeup water, indicating
leaks in system.
Condensate return piping:e.
Satisfactory operation of any steam heating system depends on •
adequate return of condensate to maintain steady water level.
Avoid adding excessive amounts of raw make-up water.•
Where condensate return is not adequate, a low water cutoff •
with pump control, condensate receiver, and condensate boiler
feed pump should be installed.
See • Figure 21 for piping and Figure 22 for sizing.
Cold water fill piping
Condensate piping to boiler
Condensate receiver capacity required
Boiler
model number
I=B=R gross output
(lbs steam per hour)
Gallons condensate
per hour
Minimum condensate receiver capacity (gallons) (Note 1) Recommended condensate
feed pump capacity
GPM at 15 PSI
15-minute boiler
operation
30-minute boiler
operation
45-minute boiler
operation
60-minute boiler
operation
488
810 97 29 58 87 116 3.2
488R
794 95 28 57 85 114 3.1
588
1084 130 39 78 117 156 4.3
688
1358 163 49 98 147 196 5.4
788
1632 195 59 117 176 234 6.5
888
1904 228 68 137 205 273 7.6
988
2170 261 78 157 235 313 8.7
988R
1991 239 72 145 217 289 8.0
1088
2452 294 88 176 265 353 9.8
1088R
2304 277 83 166 249 332 9.2
1188
2724 327 98 196 294 392 10.9
1288
3000 360 108 216 324 432 12.0
1388
3270 392 117 235 353 470 13.1
1488
3550 426 127 255 383 511 14.2
1588
3820 458 137 274 412 550 15.3
1688
4090 490 147 294 441 588 16.4
1688R
3980 478 143 287 430 574 15.9
1788
4370 524 157 314 471 629 14.5
1888
4640 557 167 334 501 668 18.6
Note 1 — Maximum time to when condensate returns to boiler — the longer the time for condensate to return, the larger the receiver must be.
