How to hide old price for products without discount?

[kostianev]

Hello, I`m trying to hide the old price for products in product details page and category page, which are without discount, because the old price is the same with sale price.
I am using Themler for my template and there I can add Custom CMS code, which to show the old price with condition if the product has discount.
They discribe shortcodes and condition here: http://answers.themler.com/articles/67028/tips-and-tricks#t_price, but not working for me, the system can't recognize if the product has discount and show prices for every product. Can someone help me with exact code for product_template and category products pages.

See my video demo with the issue: https://db.tt/CzeSlpLfbr