[tony_sologubov]

You have two ways to achieve it:

1) Via template
- Enable Custom Skin module or create your own one (I believe, you already created one) that registers skins
- Create the template main.header.tpl that will replace default one, so its code will be as follows:

<div id="header-area">
{*
commenting out mini-cart widget
  <div class="desctop_header">
    <list name="layout.header" />
  </div>
*}

  <list name="layout.header.mobile" />
</div>

This template will sit in the skins/custom_skin/default/en/layout/ folder if you are using Custom Skin module.

If you are using your own module, it will sit in the <PATH-TO-YOUR-CUSTOMER-SKIN>/en/layout/main.header.tpl

Finally, the whole process is described here:
http://kb.x-cart.com/pages/viewpage.action?pageId=7504837#Webinar2-10Apr2014-DesignchangesinX-Cart5(Custom...stomSkinmodule
http://kb.x-cart.com/pages/viewpage.action?pageId=7504837#Webinar2-10Apr2014-DesignchangesinX-Cart5(Custom...ridingtemplate

2) Via PHP code

This process is described here:
http://kb.x-cart.com/pages/viewpage.action?pageId=7504837#Webinar2-10Apr2014-DesignchangesinX-Cart5(Custom...-2.2.ByPHPcode

In this case, you need to create runBuildCacheHandler() method in your Main.php file and call there something like:

PHP Code:

public static function runBuildCacheHandler()
    {
        parent::runBuildCacheHandler();
 
        \XLite\Core\Layout::getInstance()->removeTemplateFromLists('layout/main.header.tpl');
    } 


Please, let me know if it helps.