20
Operating Switch
PHP Water Heater Control Switch Operation Instructions
PHP Coolant Heater Operating Switch Instructions R4_DallasEDIT.doc
2
June 9, 2020
On / Off Control:
Press and hold 3 sec. to start heater
Displayed for 3 seconds
Displays max. then actual coolant
temp.
Press and hold 3 sec. to stop heater
NOTE: Heater will initiate a 3 minute cool down cycle.
Displayed for 3 seconds
Disappears
Operating Modes:
The heater is designed to function in two different operating modes.
“Water Temp” mode allows you to control the maximum engine coolant temperature that the heater
will maintain. This is the most common operating mode. This mode allows you to set the desired
maximum operating temperature from 30
℃
to 75
℃
. While operating in this mode, the heater will switch
on and off according to the requirements to maintain the desired maximum temperature.
“Automatic Climate - A/C” mode allows you to control the maximum cabin temperature that the heater
will maintain. This is a less common operating mode and is only practical for use with cargo and cabin
heating applications. This mode allows you to set the maximum cabin temperature from 14
℃
to 40
℃
(As
measured at the Control Switch). In this mode the heater will maintain a coolant temperature between
60
℃
and 75
℃
. However, once the maximum cabin temperature is reached, the heater will go into
standby mode.
When heater is initially started for the first time it will start in “WaterTemp” Mode. Subsequent starts will
be in the last used mode “WaterTemp” or “ A/C”
Switching Between Operating Modes:
To switch heater between “WaterTemp” Mode and “A/C”
Mode;
Press. three times.
“WaterTemp” or “A/C” mode will be
indicated by the corresponding icon.
Or
The corresponding, current Engine Coolant
Temperature or Cabin Temperature will also
be displayed.
On
Off
WaterTemp
A/C
40ºC
