How do I format a timespan to show me total hours?

I want to save the user's hours worked in a database varchar column, but by default, the formatted value includes days if the number of hours is more than 24. I just want the total number of hours.

For example: if a user works 10:00:00 hours today, then 13:00:00 hours tomorrow, and 3:30:00 hours the day after tomorrow then the formatted total I want is 26:30:00. Instead, I am seeing 1.2:30:00.

How can I get the formatting I want?

Also, when I save the value 40:00:00 in the database manually, and try to read it into a TimeSpan later, I get a bug.

How can I save the hours in the database the way I want, and still be able to read it back into a TimeSpan later?