Page 42
4.14
Plumbing Guidelines
Use at least the MINIMUM pipe size for the entire
boiler loop piping (connecting boiler to and from
the primary/secondary connection). Use only
primary/secondary piping as shown.
Failure to follow these guidelines could result in
system problems.
CH pipe minimum size : 1˝
DWH pipe minimum size : 3/4˝
For guidelines in the use of Glycol Products.
Please refer to Section 8.3 on page 76
4.14.1
External Plumbing and Water
Connection Guidelines
- Ensure pipe material meets local codes and
industry standards.
- The pipe end must be clean and free of debris.
- Do not apply torch heat within 12˝ of the bottom
connections of the unit.
- The size of the DHW pipe should be 3/4˝
diameter and central heating water pipe should
be 1˝ diameter.
- Isolation valves(Shutoff valve) will be used.
- All piping should be insulated.
4.14.2
Applicable Backflow Preventer
- Apply a backflow preventer valve in the DHW
supply inlet (water Inlet) to the unit as required by
local codes.
4.14.3
Closed type Expansion tank
- Apply 1" pipe to the expansion tank
to allow air within the system for exhausting.
- Pitch any horizontal piping up towards tank 1
inch per 5 feet of piping.
- DO NOT install automatic air vents on closed
type expansion tank systems. Air must remain in
the system and return to the tank to provide its
air cushion.
- DO NOT use a closed type expansion tank in
a system with the FT Combination Boiler. (Au
-
tomatic air vent has been installed inside of the
boiler.)
- If the combination boiler is installed in a closed
water supply system, such as one having a back
-
flow preventer in the cold water supply line, it will
control thermal expansion.
4.14.4
Diaphragm Type Expansion Tank
- The air in a diaphragm-type expansion tank is
separated from the water by a flexible rubber
membrane. When the tank is installed in and
connected to the piping of the system, water
enters the other side of the tank chamber and
presses down on the diaphragm.
- You should always install an ‘Automatic Air Vent
(Under figure ‘A’)’ on the top of the air separator
to remove residual air from the system.
- Automatic air vent has been installed on the
inside of the FT combination boiler.
- The installation of additional air vent is optional.
- If the combination boiler is installed in a closed
water supply system, such as one having a
backflow preventer in the cold water supply line,
it will control thermal expansion.
- Pump for primary loop is included with FT for
<
15 ft.
CAUTION
CAUTION
