Hello,
Did you make changes to Boot records? such as installing OS etc.. if yes, it will make changes that leads for the product not not trigger recovery from partition. i think you need to use HP recovery media.
This should help get the media.
http://h10025.www1.hp.com/ewfrf/wc/document?cc=us&lc=en&docname=bph07143
alternatively, Please visit www.hp.com ; select country from the bottom left handside if you are outside USA.
now please select "support and drivers" > now click drivers & software> input model number of your computer. (if the list is populated incase similar models are there in this series, select the model you have)
select the OS you recieved this with computer and click next > now you should get one option "order recovery media - select that and under that you have type of media available. select and media you want.
incase you have issue in ordering media; you can try after sometime and/or contact HP support to get the media ordered.
also for few countries or products recovery order online may not be available; in such cases, please visit region/country website ( www.hp.com and select country). click connect with HP and contact HP. email/phone support numbers are available, please contact support team to place an order for your product in specific country(if available).
hope it helps, Good Luck !!!