Delta F-25 - Manual (Page 22)

Primary Piping
SECTION V - Primary Piping
General Piping Requirements
Low Water Cutoff Device
- The ELITE is equipped with a factory
installed pressure switch style Low Water
Cut Off device.
- The minimum operating system pressure
allowable with this device is 10 psig.
- Check local codes which require a low
water cutoff device for compliance of
this device.
Backflow Preventer
- Use a backflow preventer valve in the
make-up water supply to the unit as
required by local codes.
Primary System Piping Applications
All piping applications shown in this instal-
lation manual utilize a primary/ secondary
piping arrangement. This method is rec-
ommended as a means to provide priority
to the production of domestic hot water.
For other piping arrangements, consult the
Engineering Department at Triangle Tube
or consult other approved/recognized
design arrangements.
On piping applications utilizing a single
zone or other recognized piping design
arrangements it is recommended the
installer uses flow/check valves with
weighted seats at or near the appliance to
prevent gravity circulation.
Expansion Tank and Makeup Water
Ensure the expansion tank is properly sized
for the outer tank volume (22 gallons) and
the system volume and temperature.
Undersized expansion tanks will cause sys-
tem water to be lost through the pressure
relief valve and cause additional makeup
water to be added to the system. Eventual
primary tank failure can result due to this
excessive makeup water addition.
The expansion tank must be located as
shown in Fig. 7, 7A or 7B page 20 or as per
recognized design methods. Refer to the
expansion tank manufacturer instructions
for additional installation details.
Connect the expansion tank to an air sepa-
rator only if the air separator is located on
the suction side (inlet) of the system circu-
lator. Always locate and install the system
fill connection at the same location as the
expansion tank connection to the system.
Diaphragm (Bladder) Expansion Tank
Always install an automatic air vent on the
top of the air separator to remove residual
air from the system.
Closed-Type (Standard) Expansion Tank
It is recommended to pitch any horizontal
piping toward the expansion tank 1 inch per
5 feet of piping. Use 3/4” piping for the
expansion tank to allow air within the sys-
tem to rise.
For proper operation of the expansion tank
and system, remove the factory installed
automatic air vent from the ELITE and
plug the connection. (See Item 10, Fig. 28
page 50)
CAUTION
BEST PRACTICE
BEST PRACTICE
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