try to pre-remove heka config dir
diff --git a/heka/server.sls b/heka/server.sls
index d4d464a..8415e47 100644
--- a/heka/server.sls
+++ b/heka/server.sls
@@ -5,6 +5,11 @@
   pkg.installed:
   - names: {{ server.pkgs }}
 
+purge-heka-conf-dir:
+  file.directory:
+  - name: /etc/heka/conf.d/
+  - clean: True
+
 /etc/heka/conf.d/00-hekad.toml:
   file.managed:
   - source: salt://heka/files/00-hekad.toml
@@ -13,6 +18,7 @@
   - group: heka
   - require:
     - pkg: heka_packages
+    - file: purge-heka-conf-dir
 
 heka_service:
   service.running: