WarmFlo HD320, Installation & Operating Instructions Manual

10/04/2007 13 

NI802 

Electric Furnace Control – 

Inside View, Right Board

Room Thermostat Type 

On the control board left side is a peg jumper which needs to point either to conventional heat/cool or 
heat pump thermostat. 

Heat Minimal Blower Speed Selection 

This is only used with H/C thermostat.  With heat pump thermostat, heat jumper has no function.  On the 
right side is a peg jumper for a LO/MED/HI selection.  The WarmFlo technology and action of both of 
the remote sensors will determine the full speed or maximum CFM when required by the heating system.  
This selection is simply a first step blower speed and does not necessarily have to match the kW capacity.  
The suggestions are as following, but 20 kW will function just fine with the LO position. 

ƒ

10 kW   LO   765 CFM 

ƒ

15 kW   MED   900 CFM 

ƒ

20 kW   HI   1035 CFM 

Cool Blower Speed Selection 

At the control board right side is A/B/C/D selection.  It is very important that this selection be matched to 
the cooling ton installed within the system.  When using a heat pump stat , cool jumper relates to heating 
and cooling.  Heat jumper is non-active. 

ƒ

A – 3-3.5 ton   1200 CFM 

ƒ

B – 2.5-3 ton   1100 CFM 

ƒ

C – 2-2.5 ton   1000 CFM 

ƒ

D – 2 ton   900 CFM 

Heat Pump 

When using a heat pump thermostat select the COOL A/B/C/D jumper position relating to the heat pump 
size. 
 

Operation Indicators 

WarmFlo Controller – 

Inside View, Left Board

Monitor LED’s on Front 
Green LED

When illuminated WarmFlo II is receiving 24V power.  Under all normal operating modes, this should be 
solid green. 

ƒ

As a secondary function this green LED provides status of the two remote sensors.  If a 
sensor is inoperative, incorrectly wired, or malfunctioning; this monitor light is in a blinking 
or pulsing mode.  By checking the pulsing pattern, the appropriate sensor can be identified. 

ƒ

OT sensor - 1ØØ ms blink every second. 

ƒ

ST sensor - two, 1ØØ ms blinks every second. 

ƒ

Both bad - ½ second on, ½ second off, alternating. 

Amber LED 

When illuminated WarmFlo II is in the electric heat operating mode (Utility Load Control). 

Inside Warmflo Board, Red LED’s 

The four red LED’s next to the output connector, indicate Stage 1, 2, 3, and 4 operation (Stage 1 is on the 
top). 
 

Electric Furnace Control – 

Inside View, Right Board

Green, next to Fuse 

24-volt power connected and fuse good.