Laars MFTHW199 - Page 44

LAARS Heating Systems
Page 42
Do not exceed 12" apart
PRIMARY LOOP
SECONDARY LOOP (SPACE HEATING)
CH SUPPLY
(SPACE HEATING)
PRIMARY/SECONDARY
CONNECTION
CH RETURN
Circulation pump
Pressure relief valve
Expansion tank
Air separator
(Closed type)
Isolation valve
Check valve
Gate valve
4.14 Plumbing Guidelines
Diaphragm type Expansion tank
- The air in a diaphragm-type expansion tank is
separated from the water by a exible 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
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 Kiturami boiler.
- The installation of additional air vent is optional.
- If the boiler is installed in a closed water supply
system, such as one having a backow preventer
in the cold water supply line, it will control thermal
expansion.
Figure 9. Plumbing Diagram using a Diaphragm Type Expansion Tank