[DATE, ex. Monday, March 31, 2008]

[NAME, COMPANY AND ADDRESS, ex.
Link Building
XYZ Inc.
1234 First Street
Suite 567
Anycity, Anystate  85245]

Dear [NAME, ex. Link Building],

Unfortunately, the [PRODUCT, ex. Cold Elite Air Conditioner unit you installed in our premises] on [DATE, ex. June 1, 1998] is malfunctioning. [STATE NATURE OF MALFUNCTION(S), ex.  Instead of cold air, the unit expels room-temperature air.]

I would like to arrange an appointment for service under warranty #[WARRANTY NUMBER] (a copy of which is enclosed, along with the sales receipt).  Please call [NAME, ex. me] at XXX-XXXX so that we can determine a mutually-convenient time.

Sincerely,

[YOUR NAME, ex. Jill Jones]