Armstrong International
IOM-706 V2.0
Flo-Direct Water Heater
Page 42 of 45
Controller: The controller is a Powers 535-1112ABD000 model. This is a fully programmable controller that must be programmed
in order to work with the Flo-Direct. These are all pre-programmed and tested before leaving the factory, however, if a
replacement controller is installed, the new will have to be programmed as specified in the documentation sent with the Flo-
Direct.
This controller has three “dry” contacts and a 4-20 mA DC output, two of the “dry” contacts are to drive the actuator one way or
the other, a spare “dry” contact is available for use as an alarm, etc. A 4-20 mA DC output is available to transmit various analog
values such as set point, process variable, etc.
The input is set via internal jumpers for an RTD. In addition, there are five special contacts that can cause the controller to perform
various functions. The designated output (“d-out”) function is always used. When this “dry” contact is closed, the controller will
go to manual mode and 0% output. The controller must be in this mode and output in order for the Flo-Direct to start. Other
special functions are possibly as a second set-point and possibly the ability to accept a remote set-point. Please refer to the
specific program listing, electrical schematic, and the Powers manual for more detail.
Operation:
The operator should not have to do anything during normal operation of a modulating Flo-Direct except change the set-point.
NOTE 1: The operating modes of the heater and Powers controller (modulation) are independent. When the heater is in "AUTO"
mode, the Powers controller must be in manual mode when the heater is not running; once flame is established, it will switch to
auto mode. When the heater turns off, it will switch back to manual mode.
Do not adjust the "MANUAL" button on the Powers
controller.
Heater in "AUTO" mode
not running
Heater in "AUTO" mode
running
Powers controller
must be in
"MANUAL" mode.
Heater in "AUTO"
mode
