Response to Hi, Abel. To achieve at least 1 degree temperature increase an hour,  you will need at least a 200,000 BTU unit. A larger unit will provide you with a faster temperature increase. 

An image is worth 1,000 words! Add an image or two to your comment to help ensure it is understood accurately.

Yes, please email me exclusive discounts, swimming pool tips and helpful how to guides. This comment may be posted on a public site. Do not include: HTML, references to other retailers, pricing, personal information, or any profane, inflammatory language.