diff --git a/definitions/grib1/section.1.def b/definitions/grib1/section.1.def
index 1ed21d91e..e1ad6471d 100644
--- a/definitions/grib1/section.1.def
+++ b/definitions/grib1/section.1.def
@@ -319,7 +319,12 @@ alias time.stepType=stepType;
 # ECC-457: GRIB1 to GRIB2 conversion
 concept_nofail stepTypeForConversion (unknown, "stepTypeForConversion.def", conceptsDir2, conceptsDir1);
 if (stepTypeForConversion is "accum" ) {
-    alias productDefinitionTemplateNumber=eight;
+    if (productDefinitionTemplateNumber == 1) {
+        alias productDefinitionTemplateNumber=eleven;
+    }
+    else {
+        alias productDefinitionTemplateNumber=eight;
+    }
 }
 
 meta md5Section1 md5(offsetSection1,section1Length);
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index e442182c1..8fa904776 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -82,6 +82,7 @@ if( HAVE_BUILD_TOOLS )
         grib_ecc-1170
         grib_ecc-1195
         grib_ecc-1212
+        grib_ecc-1230
         bufr_ecc-1195
         bufr_json_samples
         bufr_ecc-359
diff --git a/tests/grib_ecc-1230.sh b/tests/grib_ecc-1230.sh
new file mode 100755
index 000000000..a9e5265e4
--- /dev/null
+++ b/tests/grib_ecc-1230.sh
@@ -0,0 +1,48 @@
+#!/bin/sh
+# (C) Copyright 2005- ECMWF.
+#
+# This software is licensed under the terms of the Apache Licence Version 2.0
+# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
+# 
+# In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
+# virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
+#
+
+. ./include.sh
+set -u
+REDIRECT=/dev/null
+label="prod_ECC-1230-test"
+temp1=temp1.$label
+temp2=temp2.$label
+sample_grib1=$ECCODES_SAMPLES_PATH/GRIB1.tmpl
+
+# paramId 228 is "Total precipitation" (=tp)
+# ------------------------------------------
+${tools_dir}/grib_set -s \
+type=pf,localDefinitionNumber=30,stream=enfo,\
+perturbationNumber=10,numberOfForecastsInEnsemble=51,indicatorOfParameter=228 \
+$sample_grib1 $temp1
+grib_check_key_equals $temp1 "stepTypeForConversion" "accum"
+grib_check_key_equals $temp1 "paramId,shortName,productDefinitionTemplateNumber" "228 tp 11"
+
+# Convert
+${tools_dir}/grib_set -s edition=2 $temp1 $temp2
+grib_check_key_equals $temp2 "productDefinitionTemplateNumber" "11"
+grib_check_key_equals $temp2 "numberOfForecastsInEnsemble,perturbationNumber" "51 10"
+
+
+# Now check 2m temperature (not accumulated)
+# ------------------------------------------
+${tools_dir}/grib_set -s \
+type=pf,localDefinitionNumber=30,stream=enfo,\
+perturbationNumber=10,numberOfForecastsInEnsemble=51,shortName=2t \
+$sample_grib1 $temp1
+grib_check_key_equals $temp1 "productDefinitionTemplateNumber" "1"
+# Convert
+${tools_dir}/grib_set -s edition=2 $temp1 $temp2
+grib_check_key_equals $temp2 "productDefinitionTemplateNumber" "1"
+grib_check_key_equals $temp2 "numberOfForecastsInEnsemble,perturbationNumber" "51 10"
+
+
+# Clean up
+rm -f $temp1 $temp2