Weil-McLain 550-110-260/02002 3c Water piping — multiple zones, GOLD CGs Gas-FiredWater Boiler

GOLD CGs Gas-Fired Water Boiler

3c Water piping — multiple zones

Piping multiple zones Follow instructions on pages 14 and 15 to install near-boiler or single-zone piping. (Also refer to Piping for radiant heating systems or converted gravity systems, below, if applicable.)

See Figure 6 or Figure 7 to complete installation.

Zoning with circulators, return temp over 130 °F

Zoning with zone valves, return temp over 130 °F

Piping for radiant heating systems or converted gravity systems

1.Size each circulator to individual circuit requirements.

2.Do not install circulator on boiler (except for primary/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 circulator.

1.Install isolation (balancing) valves to adjust flow to distribute heat to all zones.

2.Provide a separate 24-volt transformer to power the zone valves. Size the transformer to handle the total rated load of all connected zone valves.

Converted gravity (or steam) systems

Whenever possible, use the primary/secondary piping shown in Figures 8 or 9 on page 19. This piping design allows changing boiler flow rate without affecting primary circuit flow rate.

If Figures 8 or 9 cannot be used, use the boiler-bypass piping shown in Figure 10 or Figure

11on page 21. You can also use the piping shown in Figure 12 on page 23 (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 sections or burners, resulting in severe personal injury, death or substantial property damage.

Radiant heating systems

Preferably, use primary/secondary piping, as shown in Figures 8 or 9 on page 19. Alternatively, use the method of either Figure 10 or Figure 11 on page 21. Do not use the piping of Figure 12 (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 damage.

16 Part number 550-110-260/0200