Delta PG PLUS-25 warranty Primary Piping Section V Primary Piping

Primary Piping
SECTION V - Primary Piping
	NOTICE
General Piping Requirements		potential outer tank failures the
	To prevent
Low Water Cutoff Device	primary system piping must be a “closed”
	loop system to avoid any oxygen contami-
- The PERFORMANCE PLUS is equipped	nation of the boiler water.
with a factory installed pressure switch
style Low Water Cut Off device.	Expansion Tank and Makeup Water
- The minimum operating system pressure
	Ensure the expansion tank is properly sized
allowable with this device is 10 psig.
	for the outer tank volume (20 gallons) and
- Check local codes which require a low
	the system volume and temperature.
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

BEST PRACTICE

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.

BEST PRACTICE

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.

CAUTION

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 Figure 11, 11A or 11B page 23 or as per recognized design methods. Refer to the expansion tank manufacturer instruc- tions 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.

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