Weil-McLain Gold CGa - Manual (Page 18)

GOLD CGa Gas-Fired Water Boiler — Boiler Manual
18
Part Number 550-101-009/0107
Water piping — multiple zones
Piping multiple zones
Follow instructions on pages 1 and 1 to install near-
boiler or single-zone piping. (Also refer to Piping for
radiant heating systems or converted gravity sys-
tems, below, if applicable.)
See Figure 11 or Figure 12 , page 19, to complete in-
stallation.
Zoning with circulators (Figure 11)
(return temp over 130°F)
1. Size each circulator to individual circuit require-
ments.
. Do not install circulator on boiler (except for pri-
mary/secondary piping).
3. Install isolation (balancing) valves to adjust flow to
distribute heat to all zones.
4. Install and wire a separate relay for each zone cir-
culator.
Zoning with zone valves (Figure 12)
(return temp over 130°F)
1. Install isolation (balancing) valves to adjust flow to
distribute heat to all zones.
. Provide a separate 4-volt transformer to power the
zone valves. Size the transformer to handle the total
rated load of all connected zone valves.
3c
Piping for radiant heating
systems or converted gravity
systems
Converted gravity (or steam) systems
Whenever possible, use the primary/secondary piping
shown in Figures 13 or 14 on page 1. This piping de-
sign allows changing boiler flow rate without affecting
primary circuit flow rate.
If
Figures 13 or 14 cannot be used, use the boiler-bypass
piping shown in Figure 15 or Figure 16 on page 3. You
can also use the piping shown in Figure 17 on page 5
(system-bypass), if the reduced flow rate in the heating
system will not cause heat distribution problems.
Failure to prevent low return water
temperature to the boiler could
cause corrosion of the boiler sec-
tions or burners, resulting in severe
personal injury, death or substantial
property damage.
Radiant heating systems
Preferably, use primary/secondary piping, as shown
in Figures 13 or 14 on page 1. Alternatively, use the
method of either Figure 15 or Figure 16 on page 3.
Do not use the piping of Figure 17 (system-bypass),
because this method does not control radiant system
supply temperature.
If radiant system tubing has no oxygen barrier, a
heat
exchanger must be used.
Radiant heating system piping should include a means of regulating the boiler return water
temperature and the system supply temperature (such as provided by an injection pumping
control). Boiler return water temperature will be adequately controlled using the methods
shown in this manual provided the system supply temperature is relatively constant.
DO NOT apply the methods in this manual if the system is equipped with an outdoor reset
control . Instead, provide controls and piping which can regulate the boiler return water
temperature at no less than 130°F regardless of system supply temperature. Contact your
Weil-McLain representative for suggested piping and control methods. Failure to prevent
cold return water temperature to the boiler could cause corrosion damage to the sections
or burners, resulting in possible severe personal injury, death or substantial property dam-
age.