Hi,
I saw the same problem in version 1.6.1.14.
I detected, the problem is the call to function convertPrice, is missing in the TPL.
I changed the files, product-list.tpl and product-tpl
{*if !$priceDisplay}{convertPrice price=$product.price}{else}{convertPrice price=$product.price_tax_exc}{/if*}
{if !$priceDisplay}{Tools::convertPrice($product.price)}{else}{Tools::convertPrice($product.price_tax_exc)}{/if}
Regards,