Mega-Stor Indirect Fired Water Heater Installation Manual
11
VII. PIPING
1) BOILER SIDE PIPING
Figures 7.1 thru 7.4 show typical boiler side piping for several common situations. Regardless of which system is used it is impera-
pump. To determine the pipe/pump sizes required see page 6.
The systems shown in Figures 7.1 thru 7.4 are described below:
STANDARD CIRCULATOR ZONE
This system is just like the circ zone system on a straight heat job except that one of the zones goes to the MS tank instead of radia-
tion. As on any circulator zone system, check valves should be installed in each zone to prevent unwanted circulation through zones
which are not calling for heat. Figure 7.1 illustrates typical circ zone piping.
ZONE VALVE SYSTEM
Figure 7.2 illustrates a typical Mega-Stor installation using zone valves. The circulator must be large enough to move boiler water
3-WAY ZONE VALVE SYSTEM
Figure 7.3 illustrates typical piping using a 3-way zone valve. In this system a 3-way zone valve is used which has a common
port, a “normally open” port, and a “normally closed” port. The zone valve motor is wired so as to be energized by the Mega-Stor
thermostat (see Part VIII for wiring information). The common side of the zone valve is connected to the boiler. The heating zone is
connected to the normally open side of the zone valve and the Mega-Stor coil is connected to the normally closed side of the zone
open side of the 3-way valve, to the boiler. As soon as the Mega-Stor calls for heat, the zone valve is energized, and boiler water
MEGA-STOR MANIFOLD PIPING (BOILER SIDE)
Multiple tank installations must be done in the “reverse return” manner illustrated in Figure 7.4. The reason for this is to create the
zone piping common to both tanks must be capable of moving 16 GPM (2 x 8GPM).
through each coil when two Mega-Stors of different sizes are placed in the same manifold. For this reason it is best not to mix
Mega-Stors of two different sizes in the same zone if their recovery is critical.