Totaling valuestream - JSON does not allow non-finite numbers problem

I`m going trough  valuestream entries and filtering them and saving to infotable in a service.

Basicaly im totalling values between hour A to hour B on each day for a week.

Problem is I get error when i use:

Totall+= StreamValue;

Im getting error:

"Wrapped org.json.JSONException: JSON does not allow non-finite numbers. Cause: JSON does not allow non-finite numbers."

everythign works fine if I use Totall+=1 or Totall= StreamValue;  but  +=StreamValue makes a problem.

Code used:

var params = {

                oldestFirst: undefined /* BOOLEAN */,

                maxItems: undefined /* NUMBER */,

                endDate: undefined /* DATETIME */,

                query: undefined /* QUERY */,

                startDate: undefined /* DATETIME */

};

var data = me.QueryPropertyHistory(params);

var params = {

                infoTableName : "InfoTable",

                dataShapeName : "StorageDataShape_granicd"

};

var result = Resources["InfoTableFunctions"].CreateInfoTableFromDataShape(params);

var tableLength = data.rows.length;

var newEntry = new Object();

var Once=0;

for (var y = 0; y < 7; y++)

{

        var Type1=0;

        Once=0;

        newEntry.timestamp=null;

        for (var x = 0; x < tableLength; x++)

        {

            var row=data.getRow(x);

            if(row.timestamp.getDay()===y && row.timestamp.getHours() >= FromHour && row.timestamp.getHours() < TillHour) //row.timestamp.getDay()==y

            {

                if(Once==0)

                {

                    newEntry.timestamp=row.timestamp;

                    Once=1;

                }

                Type1+= row.LM;      //problem line      

          }

       }

       newEntry.LM_Totall=Type1;

       result.AddRow(newEntry);        

}

me.Totallhours=result;