diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 17cef03..65bdd03 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -10,10 +10,10 @@ jobs:
   test:
     strategy:
       matrix:
-        go-version: [1.16.x, 1.17.x, tip]
+        go-version: [1.21.x, 1.22.x, tip]
         full-tests: [false]
         include:
-          - go-version: 1.18.x
+          - go-version: 1.23.x
             full-tests: true
 
     runs-on: ubuntu-latest
@@ -21,7 +21,7 @@ jobs:
     steps:
       - name: Setup go
         run: |
-          curl -sL https://raw.githubusercontent.com/maxatome/install-go/v3.3/install-go.pl |
+          curl -sL https://raw.githubusercontent.com/maxatome/install-go/v3.6/install-go.pl |
               perl - ${{ matrix.go-version }} $HOME/go
       - name: Checkout code
         uses: actions/checkout@v2
@@ -30,14 +30,13 @@ jobs:
         if: matrix.full-tests
         run: |
           curl -sL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh |
-              sh -s -- -b $HOME/go/bin v1.46.2
+              sh -s -- -b $HOME/go/bin v1.61.0
           echo $PATH
           $HOME/go/bin/golangci-lint run --max-issues-per-linter 0 \
                                          --max-same-issues 0 \
                                          -E asciicheck \
                                          -E bidichk \
                                          -E durationcheck \
-                                         -E exportloopref \
                                          -E gocritic \
                                          -E godot \
                                          -E goimports \
@@ -54,7 +53,7 @@ jobs:
           if [ ${{ matrix.full-tests }} = true ]; then
               GO_TEST_FLAGS="-covermode=atomic -coverprofile=coverage.out"
           fi
-          go test $GO_TEST_FLAGS ./...
+          go test $GO_TEST_FLAGS .
       - name: Reporting
         if: matrix.full-tests
         env:
diff --git a/cmd/vitotrol/actions.go b/cmd/vitotrol/actions.go
index 58295fb..0613f31 100644
--- a/cmd/vitotrol/actions.go
+++ b/cmd/vitotrol/actions.go
@@ -4,7 +4,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"strconv"
 	"strings"
 
@@ -239,7 +239,7 @@ type devicesAction struct {
 	authAction
 }
 
-func (a *devicesAction) Do(pOptions *Options, params []string) error {
+func (a *devicesAction) Do(pOptions *Options, _ []string) error {
 	err := a.initVitotrol(pOptions)
 	if err != nil {
 		return err
@@ -267,7 +267,7 @@ func (a *listAction) NeedAuth() bool {
 	return false
 }
 
-func (a *listAction) Do(pOptions *Options, params []string) error {
+func (a *listAction) Do(_ *Options, params []string) error {
 	if len(params) == 0 || params[0] == "attrs" {
 		for _, pAttrRef := range vitotrol.AttributesRef {
 			fmt.Println(pAttrRef)
@@ -419,7 +419,7 @@ type errorsAction struct {
 	authAction
 }
 
-func (a *errorsAction) Do(pOptions *Options, params []string) error {
+func (a *errorsAction) Do(pOptions *Options, _ []string) error {
 	err := a.initVitotrol(pOptions)
 	if err != nil {
 		return err
@@ -465,7 +465,7 @@ func (a *setTimesheetAction) Do(pOptions *Options, params []string) error {
 	tss := make(map[string]vitotrol.TimeslotSlice)
 	var data []byte
 	if strings.HasPrefix(params[1], "@") && len(params[1]) > 1 {
-		data, err = ioutil.ReadFile(params[1][1:])
+		data, err = os.ReadFile(params[1][1:])
 		if err != nil {
 			return fmt.Errorf("Cannot read file %s: %s", params[1][1:], err)
 		}
@@ -548,7 +548,7 @@ type remoteAttrsAction struct {
 	authAction
 }
 
-func (a *remoteAttrsAction) Do(pOptions *Options, params []string) error {
+func (a *remoteAttrsAction) Do(pOptions *Options, _ []string) error {
 	err := a.initVitotrol(pOptions)
 	if err != nil {
 		return err
diff --git a/go.mod b/go.mod
index 2cce2d3..24de260 100644
--- a/go.mod
+++ b/go.mod
@@ -2,6 +2,6 @@ module github.com/maxatome/go-vitotrol
 
 go 1.18
 
-require github.com/maxatome/go-testdeep v1.11.0
+require github.com/maxatome/go-testdeep v1.14.0
 
 require github.com/davecgh/go-spew v1.1.1 // indirect
diff --git a/go.sum b/go.sum
index c446431..1979d1d 100644
--- a/go.sum
+++ b/go.sum
@@ -1,23 +1,4 @@
-github.com/davecgh/go-spew v0.0.0-20180221232628-8991bc29aa16 h1:HqkufMBR7waVfFFRABWqHa1WgTvjtVDJTLJe3CR576A=
-github.com/davecgh/go-spew v0.0.0-20180221232628-8991bc29aa16/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/maxatome/go-testdeep v1.0.3 h1:xTds+j0BxPnSJbBEc3jqj8M6mUcffoIGbXCUgCs7Ybc=
-github.com/maxatome/go-testdeep v1.0.3/go.mod h1:n887vr2m8DvuP4YfGAZBug2HhsEiVOC+RMvCDxo70X4=
-github.com/maxatome/go-testdeep v1.0.4 h1:Oq/Hr9suAUJ3p11Xr2bcpN4Urlv1ZgJ8FysHGQvYTNo=
-github.com/maxatome/go-testdeep v1.0.4/go.mod h1:n887vr2m8DvuP4YfGAZBug2HhsEiVOC+RMvCDxo70X4=
-github.com/maxatome/go-testdeep v1.0.5/go.mod h1:n887vr2m8DvuP4YfGAZBug2HhsEiVOC+RMvCDxo70X4=
-github.com/maxatome/go-testdeep v1.3.0 h1:r66U/hnWMFYAEwbHeZvJWmTGfXddhZ8TzHSzi2kMFJo=
-github.com/maxatome/go-testdeep v1.3.0/go.mod h1:011SgQ6efzZYAen6fDn4BqQ+lUR72ysdyKe7Dyogw70=
-github.com/maxatome/go-testdeep v1.4.0 h1:vKQh3/lHKAMsxggya/fXB6fLbf70c7k6wlLveuS9sKE=
-github.com/maxatome/go-testdeep v1.4.0/go.mod h1:011SgQ6efzZYAen6fDn4BqQ+lUR72ysdyKe7Dyogw70=
-github.com/maxatome/go-testdeep v1.7.0 h1:FdH/t2zHa+I43pKIjeUAwfUPoSADSkX0NwY6nvvxT7o=
-github.com/maxatome/go-testdeep v1.7.0/go.mod h1:011SgQ6efzZYAen6fDn4BqQ+lUR72ysdyKe7Dyogw70=
-github.com/maxatome/go-testdeep v1.8.0 h1:7QpuvRvyCUefU41jbEU1+k8N4DhuE6jbu/CvFeUUOhU=
-github.com/maxatome/go-testdeep v1.8.0/go.mod h1:011SgQ6efzZYAen6fDn4BqQ+lUR72ysdyKe7Dyogw70=
-github.com/maxatome/go-testdeep v1.9.2 h1:5D7u/JkeG0A/HDTbZ/CFFmpYZPeWN+uGQ1IbsEHYlCo=
-github.com/maxatome/go-testdeep v1.9.2/go.mod h1:011SgQ6efzZYAen6fDn4BqQ+lUR72ysdyKe7Dyogw70=
-github.com/maxatome/go-testdeep v1.10.0 h1:s1pP+gqiylIm2Fqhscvec1bnvGmCLayVQW8iFkGNGKw=
-github.com/maxatome/go-testdeep v1.10.0/go.mod h1:011SgQ6efzZYAen6fDn4BqQ+lUR72ysdyKe7Dyogw70=
-github.com/maxatome/go-testdeep v1.11.0 h1:Tgh5efyCYyJFGUYiT0qxBSIDeXw0F5zSoatlou685kk=
-github.com/maxatome/go-testdeep v1.11.0/go.mod h1:011SgQ6efzZYAen6fDn4BqQ+lUR72ysdyKe7Dyogw70=
+github.com/maxatome/go-testdeep v1.14.0 h1:rRlLv1+kI8eOI3OaBXZwb3O7xY3exRzdW5QyX48g9wI=
+github.com/maxatome/go-testdeep v1.14.0/go.mod h1:lPZc/HAcJMP92l7yI6TRz1aZN5URwUBUAfUNvrclaNM=
diff --git a/time.go b/time.go
index d1327ba..2a70b98 100644
--- a/time.go
+++ b/time.go
@@ -25,7 +25,9 @@ func (t *Time) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
 }
 
 // String returns the time formatted using the format string
+//
 //	2006-01-02 15:04:05
+//
 // considered as being a localtime value.
 func (t Time) String() string {
 	return time.Time(t).Format(vitodataTimeFormat)
diff --git a/types.go b/types.go
index 192c16b..2343f85 100644
--- a/types.go
+++ b/types.go
@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"strconv"
+	"strings"
 )
 
 // Singletons matching Vitodata™ types.
@@ -56,19 +57,23 @@ func (v *VitodataDouble) Human2VitodataValue(value string) (string, error) {
 	if err != nil {
 		return "", err
 	}
-	return strconv.FormatFloat(num, 'f', -1, 64), nil
+	return strings.Replace(strconv.FormatFloat(num, 'f', -1, 64), ".", ",", 1), nil
 }
 
 // Vitodata2HumanValue checks that the value is a float number and
 // returns it after reformatting.
 func (v *VitodataDouble) Vitodata2HumanValue(value string) (string, error) {
-	return v.Human2VitodataValue(value)
+	num, err := strconv.ParseFloat(strings.Replace(value, ",", ".", 1), 64)
+	if err != nil {
+		return "", err
+	}
+	return strconv.FormatFloat(num, 'f', -1, 64), nil
 }
 
 // Vitodata2NativeValue extract the number from the passed string and
 // returns it as a float64.
 func (v *VitodataDouble) Vitodata2NativeValue(value string) (interface{}, error) {
-	num, err := strconv.ParseFloat(value, 64)
+	num, err := strconv.ParseFloat(strings.Replace(value, ",", ".", 1), 64)
 	if err != nil {
 		return nil, err
 	}
diff --git a/types_test.go b/types_test.go
index cac1d4d..a1a7766 100644
--- a/types_test.go
+++ b/types_test.go
@@ -14,7 +14,7 @@ func TestVitodataDouble(tt *testing.T) {
 
 	// Human2VitodataValue
 	str, err := TypeDouble.Human2VitodataValue("1.200")
-	t.CmpDeeply(str, "1.2")
+	t.CmpDeeply(str, "1,2")
 	t.CmpNoError(err)
 
 	str, err = TypeDouble.Human2VitodataValue("foo")
@@ -26,6 +26,10 @@ func TestVitodataDouble(tt *testing.T) {
 	t.CmpDeeply(str, "1.2")
 	t.CmpNoError(err)
 
+	str, err = TypeDouble.Vitodata2HumanValue("1,200")
+	t.CmpDeeply(str, "1.2")
+	t.CmpNoError(err)
+
 	str, err = TypeDouble.Vitodata2HumanValue("foo")
 	t.Empty(str)
 	t.CmpError(err)
@@ -35,6 +39,10 @@ func TestVitodataDouble(tt *testing.T) {
 	t.CmpDeeply(num, float64(1.2))
 	t.CmpNoError(err)
 
+	num, err = TypeDouble.Vitodata2NativeValue("1,200")
+	t.CmpDeeply(num, float64(1.2))
+	t.CmpNoError(err)
+
 	num, err = TypeDouble.Vitodata2NativeValue("foo")
 	t.Nil(num)
 	t.CmpError(err)
diff --git a/vitotrol.go b/vitotrol.go
index 4a4a1e4..48e8937 100644
--- a/vitotrol.go
+++ b/vitotrol.go
@@ -4,7 +4,7 @@ import (
 	"bytes"
 	"encoding/xml"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"log"
 	"net/http"
 	"sort"
@@ -55,7 +55,7 @@ func (v *Session) sendRequest(soapAction string, reqBody string, respBody HasRes
 	}
 	defer resp.Body.Close()
 
-	respBodyRaw, _ := ioutil.ReadAll(resp.Body)
+	respBodyRaw, _ := io.ReadAll(resp.Body)
 
 	if resp.StatusCode == 200 {
 		cookies := resp.Header[http.CanonicalHeaderKey("Set-Cookie")]
diff --git a/vitotrol_test.go b/vitotrol_test.go
index 9d01d0e..5a74e82 100644
--- a/vitotrol_test.go
+++ b/vitotrol_test.go
@@ -3,7 +3,7 @@ package vitotrol
 import (
 	"encoding/xml"
 	"fmt"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"reflect"
@@ -27,7 +27,7 @@ const (
 func extractRequestBody(t *td.T, r *http.Request, reqBody interface{}, testName string) bool {
 	t.Helper()
 
-	bodyRaw, err := ioutil.ReadAll(r.Body)
+	bodyRaw, err := io.ReadAll(r.Body)
 	if !t.CmpNoError(err, "%s: request body ReadAll OK", testName) {
 		return false
 	}
@@ -45,7 +45,8 @@ func virginInstance(pOrig interface{}) interface{} {
 func testSendRequestAny(t *td.T,
 	sendReq func(v *Session) bool, soapAction string,
 	expectedRequest interface{}, serverResponse string,
-	testName string) bool {
+	testName string,
+) bool {
 	t.Helper()
 
 	ts := httptest.NewServer(http.HandlerFunc(
@@ -113,7 +114,7 @@ func TestSendRequestErrors(tt *testing.T) {
 
 	// HTTP status error
 	ts := httptest.NewServer(http.HandlerFunc(
-		func(w http.ResponseWriter, r *http.Request) {
+		func(w http.ResponseWriter, _ *http.Request) {
 			w.WriteHeader(http.StatusInternalServerError)
 		}))
 	defer ts.Close()
@@ -236,9 +237,7 @@ func TestSendRequest(tt *testing.T) {
 		"sendRequest app error")
 }
 
-//
 // Login.
-//
 func TestLogin(tt *testing.T) {
 	t := td.NewT(tt)
 
@@ -294,9 +293,7 @@ func TestLogin(tt *testing.T) {
 		"Login with error")
 }
 
-//
 // GetDevices.
-//
 func TestGetDevices(tt *testing.T) {
 	t := td.NewT(tt)