Install Instructions

24
109837-01 - 5/20
PVCG-C
Installation, Operating & Service Manual
10. Drain Valve - The drain valve is shipped in the
boiler parts bag. Install it in the 3/4" tapping
as shown in Figure 7.1.
B. Piping For Special Situations
Certain types of heating systems have
additional requirements. Some of the more
common variations follow:
1. Indirect Water Heaters - Figure 7.3 shows
typical indirect water heater piping. Boiler
piping is the same as for any two-zone system.
Figure 7.3 shows circulator zoning, which is
usually preferred for indirect water heaters.
Size the circulator and indirect water heater
piping to obtain the boiler water flow through
the indirect water heater called for by the
indirect water heater manufacturer.
2. Large Water Volume and Low Temperature
Systems - Use a system bypass if boiler is to
be operated in a system which has a large
volume or excessive radiation where low boiler
water temperatures may be encountered
(i.e. converted gravity circulation system,
etc.). (See Appendix C "Low Return Water
Temperatures").
3. Systems Containing Oxygen - Many hydronic
systems contain enough dissolved oxygen
to cause severe corrosion damage to a cast
iron boiler such as this one. Some examples
include:
• Radiant systems that employ tubing
without an oxygen barrier.
• Systems with routine additions of fresh
water.
• Systems which are open to the
atmosphere.
Figure 7.3: Indirect Water Heater Boiler Side Piping
7 Water Piping (continued)