Weil-McLain EG - Manual (Page 9)

Part Number 550-110-639/0703 9
EG, PEG, EGH G
AS
-
FIRED
B
OILERS
—
SERIES
4 — B
OILER
M
ANUAL
Piping connections
2
Pipe before installing controls. Connect return piping
after jacket is attached. Connect supply piping before or
after jacket is attached.
Failure to properly pipe the boiler may
result in improper operation and damage
to the boiler or building.
Forced hot water boilers and
gravity hot water boilers
(EG Only)
1. To protect:
• radiant panels, plaster, etc. from high temperature water
supplied from boiler, or
• boiler from condensation caused by low temperature
water returned from system.
2. To protect boiler from condensation formed by low
water temperature returned from large water content
converted gravity systems, etc., see Figure 4, page 6.
Refer to tables and Figures 11a and 11b.
1. Circulator must be selected and sized according to
the design requirements of the system. Size expansion
tank to handle the volume of water in the system.
2. Small expansion tanks cause system water to be lost
from relief valve. Make-up water is then added
Figure 11a Recommended piping connections
forced hot water boilers with closed
type expansion tanks
Figure 11b Recommended piping connections
forced hot water boilers with
diaphragm type expansion tanks
through fill valve. Eventual section failure can result.
Expansion tank installation:
a) Closed type expansion tank - connect from the 3/4"
N.P.T. tapping on left end section to expansion tank
using 3/4" N.P.T. piping. Any horizontal piping must
pitch upward toward tank at least 1 inch per 5 feet of
piping.
b) Diaphragm type expansion tank - may be located
anywhere in the system, preferably near the boiler. Install
automatic air vent as shown in Figure 11b.
3. Install water relief valve vertically in “E” tapping.
Relief valve discharge piping must be piped
near floor close to floor drain to eliminate
potential of severe burns. Do not pipe to
any area where freezing could occur. Do
not plug, valve or place any obstruction in
discharge line.
4. Connect system return piping to left end for EG -
right or left for EGH. Supply and return must be on
same end of EGH boiler, for proper flow and
disposition of water throughout the sections.
5. Installer must provide drain cock(s).
6. Connect cold water fill supply piping close to boiler.
7. Plug all unused tappings.