Strainers; Isolation Valves - Watts AERCO Modulex EXT Series Technical Application Manual

Modulex EXT Series Piping
BOILER LOOP DESIGN GUIDELINES
WARNING!
There is 120 VAC between terminals Y4-1 and Y4-2 whenever the boiler is ON.

3.4. STRAINERS

AERCO requires the installation of a Y strainer to keep dirt out of the system and boiler. The strainer should
be installed in the return piping with isolation valves to allow for cleaning as necessary. The Y strainer shall
have a 20 mesh or finer strainer. Such filter shall protect the boiler from heating system dirt. It should be
regularly cleaned to prevent problems.

3.5. ISOLATION VALVES

It is MANDATORY that ball or other type of shut-off valves be installed in the system supply and return
piping to isolate the boiler if necessary. In this case the boiler can be disconnected or drained without having
to drain the whole system.
WARNING!
NEVER bypass safety devices, such as safety valves and expansion vessels.
Page 16 of 37
10.07.2010
Application Guide
Figure 3: Electrical Connection of Primary Pump
AERCO International, Inc. • 100 Oritani Dr.
Phone: 800-526-0288
Blauvelt, NY 10913 TAG-0099