Display shows "6522 Rev HH" I cannot clear the display

Thats just telling you what software is in your jandy system and what revision that software is.

click on Start > Control Panel, and choose Regional and Language Options.

Click the Customize button underneath the Standards and formats section.

Click on the Time tab and change the time format to H:mm:ss (note the uppercase H) and press OK

Below that button, you’ll also see an example of how each setting is currently configured for Number, Currency, Time, Short Date, and Long Date.

Type uppercase H or HH to Display time in a 24-hour format

Type lowercase h or hh to Display time in a 12-hour format

Type two characters, HH or hh to Display leading zeros in single-digit hours

Type a single uppercase H, or lowercase letter, such as h, m, or s to suppress the display of leading zeros in single-digit hours, minutes, or seconds

Type lowercase t to display a single letter to indicate AM or PM

Type lowercase tt to display two letters to indicate AM or PM

Type single quotation marks (’) around text to display text

Hi,


ENABLE CUSTOMER PROGRAMMING
 With the handset on-hook, dial #06. The display shows [MMC DISABLED].
 Dial the passcode and 1 and then press #.
At this point, customer programming is open. Follow instructions as needed.

TO SET TIME AND DATE::

Dial #55. Display shows [YY MM DD W HH MM].
Dial new information as follows:
YY = Last two digits of the year
MM = Month (01–12)
DD = Day of the month (01–31)
W = Day of the week (1–7; week begins on Monday and ends on
Sunday)
HH = Hour (use 24 hour clock)
MM = Minutes (00–59)
Dial # to set current date and time. The phone returns to normal use.

And here is the full operational manual:
http://pdf.textfiles.com/manuals/TELECOM-S-Z/Samsung%20Prostar%20816%20Plus%20System%20Admin%20-%20Specia.%20Features%20Guide.pdf

hopefully it works for you.

1. Enable technician programming mode
• Press "#" - "PROGRAMMING" is displayed
• Dial "20" - "MMC ENABLED" or "MMC DISABLED" is displayed
• Dial the password (default - 1234) - if wrong password is enter "ERROR" is displayed
• Dial "1" to enter program mode
• Press "#"
2. Press "#" key - "PROGRAMMING" is displayed
3. Dial "55" - the display shows "YY MM DD W HH MM" and then the current date is displayed
4. Enter the new date
• YY = Last two digits of the year
• MM = Month (01 - 12)
• DD = Day of the month (01 - 31)
• W = Day of the week (1 -7 day of the week begins on Monday & ends on Sunday)
• HH = Hour (Use 24 hour clock)
• MM = Minutes (0-59)
5. Press "#" - new date is saved

Aqualink Guide book

go into time setting and change from 12 hour 2 24 hour. reply me

First, you have to Enable Customer Programming. - With handset on-hook, dial #06. The display shows [MMC DISABLED]. - Dial the passcode and '1' and then dial #. (If you don't know the password try 1234, 4321, 9999, etc.) At this point, customer programming is open... Next, Setting the date and time. - Dial #55. Display shows [YY MM DD W HH MM]. - Dial new information as follows: YY = Last two digits of the year MM = Month (01-12) DD = Day of the month (01-31) W = Day of the week (1-7; week begins on Monday (1) and ends on Sunday (7)) HH = Hour (use 24 hour clock) MM = Minutes (00-59) - Dial # to set current date and time. The phone returns to normal use.