ORA-01841 (full) year must be between -4713 and +9999, and not be 0

I am using this query to determine which job is done in which shift.

SELECT srvb.kod AS code,
       CASE
         WHEN srvb.rectarih1 || ' ' || srvb.rectime1 >= srvb.rectarih1 || ' ' || '07:30' 
          AND srvb.rectarih1 || ' ' || srvb.rectime1 <  srvb.rectarih1 || ' ' || '15:30' THEN
          1
         WHEN srvb.rectarih1 || ' ' || srvb.rectime1 >= srvb.rectarih1 || ' ' || '15:30' 
          AND srvb.rectarih1 || ' ' || srvb.rectime1 <  srvb.rectarih1 || ' ' || '23:30' THEN
          2
         ELSE
          3
       END AS shift,
       srvb.rectarih1 || ' ' || srvb.rectime1 AS full_time,
       srvb.rectarih1 AS job_start_date,
       srvb.rectime1
  FROM srvb00O srvb
  LEFT JOIN srvbp0 srvp
    ON srvp.kod = srvb.operatorkodu
  LEFT JOIN srvb00 srv0
    ON srv0.kod = srvb.kod
  LEFT JOIN srvbc0 srvc
    ON srvc.kod = srv0.cihazkartno
 WHERE srvb.rectarih1 <> '          '
   AND srvb.rectime1  <> '          '
   AND srvb.rectarih2 <> '          '
   AND srvb.rectime2  <> '          '
-- AND sysdate-TO_DATE(srvb.rectarih1,'YYYY/MM/DD')=1
 ORDER BY srvb.kod DESC

Here is the some part of the list.

Problem I am facing here is in WHERE statement.
When I try to filter the yesterday's data by using

sysdate-TO_DATE(srvb.rectarih1,'YYYY/MM/DD')=1

I am getting this error -->

"ORA-01841:"(full) year must be between -4713 and +9999, and not be 0" Cause: Illegal year entered Action: Input year in the specified range"