8

BOILER CONNECTIONS

The Indirect connection labeled “BOILE R WATER OUT” should be piped to the boiler water return piping
as close to the boiler as possible and after any flow control or check valves in the space heating return
piping. The use of a union and a shut-off valve is recommended. The use of a flow control or check valve
is required to prevent back flow through the water heater during o peration of the space heating system.
Pipe and fittings between the boiler and Indirect should be ¾” diameter or large r.
The Indirect connection labeled “BOILE R WATER IN” should be piped to the boiler water supply piping.
Mount the circulator making sure the flow arrow points toward the water heater. The use of Shut-off
valves and unions are recommended for future service convenience. The use of an air separator and vent
is recommended to eliminate air in the system. Pipe and fittings b etween the boiler and Single-wall
Indirect must be ¾” diameter or larger.
Figure 1. – System with Zone Valves
Figure 2. – System with Circulators