how to get value of HTML element via .load via cross domain using jquery

Note, value property may set 22.25 to 22 , see console at jsfiddle , where 22 returned by element.val() , element[0].value , and element.prop("value") . 22.25 returned by element.data("value") from html data-* attribute.

Try

html

<!-- added `data-value` attributes , 
     having same `value` as `value` attributes ,
     to maintain same `data-value` when processed 
-->
<div class="temeratura">
<ul id="temperatura_lista">
  <li id="temp_Sypialnia" data-value="22.25" value="22.25">Temp. Sypialnia: 22.25</li>
  <li id="temp_MalyPokoj" data-value="19.75" value="19.75">Temp. Mały pokój: 19.75</li>
  <li id="temp_Salon" data-value="23.00" value="23.00">Temp. Salon: 23.00</li>
</ul>

js

$("#new-tempSypialnia")
.load("http://some.address.com/index.html #temp_Sypialnia #temp_Sypialnia"
, function(data) {
      var val = $(data).find("#temp_Sypialnia");

      // console.log("`elem.data('value')`:", val.data("value")
      //            , "`elem.val()`:", val.val()
      //            , "`elem[0].value`:", val[0].value); 

      var result = val.data("value");          
      alert(result);
});

jsfiddle http://jsfiddle.net/guest271314/ckLv2eub/

See

.load() , at complete callback

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