LEFT OUTER JOIN where values is empty

I have a table where I am able to sum of the count of calls based on call code... so the result looks something like this

INIT_CALLBRD_ACTION_CDNumber_of_Calls
HHFR28
RFAA4

When there are no RFAA calls, I want it to shows HHFR and RFAA and want it to return zero for RFAA?

I started with this but can't finish

(SELECT 'HHFR' AS Callboard_Action_Code
  UNION
  SELECT 'RFAA'  )

LEFT OUTER JOIN