Direct Open Loop System

Sku#: D-SYS

Item Information

The Direct Series systems are referred to as direct because the sun's heat is transferred through the collector directly to the usable waterline; no antifreeze is required. When the sun is shining, a pump circulates water from the bottom of a storage tank through collectors where it is heated, and then returned to the tank for storage and eventual use.

  • A Differential Control senses temperature differences between water leaving the collector and the coldest water in the bottom of the storage tank. When the temperature of the water in the collector is hotter than the water in the tank, the differential control operates the circulating pump.
  • Freeze protection includes a thermally operated valve installed at the collector (where required) or by manually draining.

Pre-Engineered Direct Systems

DB System Part Number Storage Tank Collector(s)
D-65-32 65 gallon one AE-32 Collector
D-65-42 65 gallon two AE-21 Collectors
D-80-40 80 gallon one AE-40 Collector
D-80-52 80 gallon two AE-26 Collectors
D-80-64 80 gallon two AE-32 Collectors
D-120-64 120 gallon two AE-32 Collectors
D-120-80 120 gallon two AE-40 Collectors

All Kits Contain:

Part Number Description
DTC-ES-1C Eagle Sun Differential Controller with 2 sensors
CP-003ST4 1/40 HP SS, Flow 0-6 GPM, Head 0-5 ft
AV-150 1/4" Air Vent
BV-50 1/2" Ball Valve Qty 2
BD-50 1/2" Boiler Drain Qty 2
PR-150 3/4? MPT Pressure Relief Valve, 150 PSI
AE-FM Flush Mounting Kit

Suggested Components:

Part Number Description
OST-65TSC or OST-80TSC or OST-120TSC Glass Lined, 4500 W Backup Heating Element, Top and Side Port
RF-50 or RF-75 Roof Flashing Set
MV-1170 3/4" FTP Mixing Valve
WH-TM24 Water Heater Timer
SK-5PLW or SK-12PLW Warranty 5 or 12 Year Premium Coverage on Service and Labor