Therma-Stor Products Group UA-135H - Manual (Page 14)

5.3I Intermittent or Programmed Ventilation
With the damper in program mode (denoted by “Pr” when setting the
damper operation) the system will operate the ventilation function
according to the current ventilation program.
There are 4 programs available for ventilation Monday through
Friday. There are also 4 programs for Saturday and 4 programs
for Sunday. No other choice of days is available. Each program
to be used has an “on event” called “START” which brings the
ventilation function on, and an “off event” called “STOP” which turns
the function off. Each START and STOP must be entered in to the
controller.
To set or adjust the ventilation program:
1. Press the “PROG” button two times. The display will indicate
“Program 1/start” at the bottom, and the hour display will flash.
2. Use the “SET” + or – button to adjust the hour for the Program 1
start time. Be sure to pay attention to the am/pm setting.
3. Press the “PROG” button again. The display will indicate “Program
1/start” at the bottom, and now the minute display will flash.
4. Use the “SET” + or – buttons to adjust to the desired minute
setting.
5. Press the “PROG” button again to move on to the “Program
1/stop” event. The display will indicate “Program 1/stop” at the
bottom, and the hour display will flash.
6. Use the “SET” + or – button to adjust the hour for the Program 1
stop time. Be sure to pay attention to the am/pm setting.
7. Press the “PROG” button again. The display will indicate “Program
1/stop” at the bottom, and now the minute display will flash.
8. Use the “SET” + or – buttons to adjust to the desired minute
setting.
9. Pressing the “PROG” button again to move onto “program 2/stop”
and begin the process again if setting the other programs. Follow
the same procedure for each program.
10. To end the program process simply leave the control alone (don’t
push any buttons) for about 10 seconds. The unit will remember
any changes and return to “home state”.
5.3J Programming Notes
To run the ventilation program, the damper mode must be in the
“program” mode (“Pr”).
The timer can be operated manually without changing the program
by adjusting the damper mode from “program” to either “on” or
“off”.
To delete a program after it has been entered, adjust the program so
the “START” and “STOP” times are identical.
Occupants should determine ventilation times and rates. Therma-
Stor makes no firm recommendations concerning when to ventilate.
Common ventilation schedules include constant ventilation,
ventilation based on occupancy times, intermittent operation, and
seasonal ventilation.
Remember the control must be on for the unit to be functioning
- make sure the green power indicator “ON” is lit.
5.3K Ventilating or Dehumidifying to Control Indoor
Relative Humidity Levels
Fresh air ventilation may have a drying effect or a wetting effect on
the indoor space, depending on the amount of moisture present in
the outdoor air. Relative humidity is not a good indicator of outside
humidity levels: use dew point measurements instead. Consider
outside humidity levels when using the ventilation function of the
dehumidifier.
5.3L Stop Start
During summer in hot, humid climates operating in ventilation mode
will increase the moisture load in the home.
Consider reducing the amount or frequency of fresh air ventilation if
indoor humidity continues to be high.
5.4 Low Pressure Control
If the low side refrigerant pressure drops to 15 PSIG, the low-
pressure control opens and shuts off the compressor and impeller
fan. It is an automatically reset control that will close when the
pressure rises to 35 PSIG. Its primary function is to prevent damage
to the compressor if a leak develops in the refrigeration system. It
may also open if the unit is A) installed in a cool area (below 50 F)
or B) installed where it is below 40 F and then started. Under these
conditions, the unit will restart within several minutes. Until the unit
warms up, it may repeat the cycle several times.
FOR HVAC INSTALLER AND HOMEOWNER
14 Ultra-Aire 135H Installer’s & Owner’s Manual