Price sorting displays random products in the ascending search

Example url that demonstrates the issue: http://demo.yes-cart.org/yes-shop/category/notebooks/page/0/sorta/facet_price_10_EUR

840 G1 with price 2615.08 is displayed first then two items with 0 price (showroom examples) then products are sorted correctly.

Some diagnostics.
It looks like when results are sorted "840 G1" is given NULL for field "facet_price_10_EUR" which is why it is pushed to the top before the 0 prices items.
However indexes appear to be correct facet_price_10_EUR for that items shows 00261508 as expected.
Interestingly this issue appears only after FULL RE-INDEX. If you navigate to the product in YUM and update it (triggering product specific entry index) the issue is resolved and sorting works as expected.

Igor, could you please investigate this (use yc230br, please)