Page 17
SERIES 28RTS/HE BOILER INSTALLATION AND OPERATION INSTRUCTIONS
Table 5 - Water Tappings
WATER BOILER PIPING - RTS
IMPORTANT NOTE!
A minimum distance of 3 ft., 0.9 m, must be maintained
between the Back Section return port and adjacent
construction behind the boiler to allow for RTS
installation and removal, Figures 1 & 18.
NOTE: See CLEANING OF WATER BOILERS before
proceeding!
The supply and return connections should be sized to suit
the system, see Figures 17, 18 and Tables 5 & 6. Do not
pipe the supply from a bottom port or the return to the top
port, the boiler will not work properly. Typical water boiler
piping arrangements are shown in Figure 22. Swing joints
should be used.
Install 3 in. nipples into the two 3 in. NPT lower tappings
in the front section and cap them.
Supply Piping
Install a reducing bushing at the 5 in. fl ange in the upper
front section to obtain the correct supply pipe size, Figure
17 and Tables 5 & 6.
Table 6 - Water Boiler Piping Sizes
Boiler Size
Return Size
Supply Size
# Sections
NPT
NPT
4 & 5
3"
3"
6 through 9
4"
4"
10 through 18
5"
5"
Note: Sizes based on 20°F, 11.1°C,
Δ
T for the system.
Return Piping - RTS Installation
NOTE: Install the smoke hood before proceeding.
1. Install 3 in. x 4 in. NPT bushings in the two 4 in NPT
tappings at the bottom of the back section. Install two 3
in NPT x 3 in. nipples with ball valves or caps, Figure 16.
2. Once the cast iron sections have been assembled
install the eight 3/4 in. x 3 in. studs in the upper rear
casting. Apply a thread sealant to the studs before
installing them, Figure 19.
Figure 19 - RTS Stud Installation
3. Install a fl ange gasket over the studs and insert the
end tube. Depending on the boiler size the end tube
will have two, three or four holes, Figure 20.
Figure 20 - End Tubes
Connect the next section per Table 7 using the brass
screws supplied, Figure 21.
NOTE: The large holes must all be facing in the
same direction for the tube to function properly.
Take care to guide the tube over the support bracket(s).
Attach the fl anged end section and slide the fl ange over
the studs, Figure 23.
NOTE: The tab on the RTS fl ange MUST be in the 9
O’clock position, Figure 23.
Tapping Size
Water
1 1/8"
Chamber
Pressure
2 3/4"
Probe
LWCO
3 3/4"
Temp./Pressure
Gage
4
3/4"
Operating Control - Top
5
3/4"
Manuel Reset High Limit
6
1"
Air
Removal
7
5"
Supply
Flange
8
3/4"
Tankless Heater Operating Control
9 1
1/2"
10
1"
Water Column - Bottom
11
3"
Boiler
Drain
12
4" Boiler
Drain
13
3"
Relief
Valve
14
Return
Flange
