Owner's Manual

60 C199 Manual
Seng Controller to Mute
On the MC-91-2 to eliminate the beeps when keys are pressed or to turn the beeps back on, press and hold both
the up and down buons unl a beep is heard (approximately 5 seconds).
Locking the Controller
The MC-91-2 controller can be locked by pressing the Priority buon and the up buon together for 5 seconds.
A beep will sound conrming that the controller is locked. The display will alternately show “LOC”, the
temperature seng, and a diagnosc code if one has been acvated. All of the controllers in the system are
also locked.
To unlock the controller press the Priority buon and the up buon together for 5 seconds.
To Display Diagnosc Informaon
To display the most recent diagnosc informaon code press and hold the “On/O” buon for 2 seconds on the
MC-91-2 controller. While holding the “On/O” buon press the up buon. The last 9 diagnosc codes will
ash one aer the other. To exit this mode press the “On/O” and up buon as before.
To enter or exit the maintenance monitor informaon mode, press and hold the down buon for 2 seconds and
without releasing it press the ON/OFF buon.
To obtain the water ow rate: press the up or down buons unl “01” displays. The water ow rate will then
appear. For example “58” means 5.8 gal/min.
To obtain the outgoing water temperature press the up or down buons unl “02” displays. The temperature
will appear in degrees Fahrenheit.

This water heater is designed to display diagnosc codes. If there is a potenal operaon concern refer to the
code and remedy on the next page.
  
Water ow rate 0.1 gal/min 01
Outgoing water temperature Degrees Fahrenheit 02
Temperature Opons Without a Temperature Controller
The default temperature seng for this appliance installed without a temperature controller is 120° F (49° C).
Default: SW5 is OFF and SW6 is ON in DIPSW1. If desired, the temperature seng can be changed to 140° F (60°
C) by seng SW5 ON and SW6 OFF in DIPSW1.