There are a number of issues you are probably dealing with as a result of a small fire in the server environment. Smoke, soot, water, and other contaminants the water may have brought (sprinkler water is a notoriously nasty mix of water, pipe cutting oil, some bio-growth, and so on). NFPA standard 75, "Standard for the protection of Electronic Computer / Data Processing equipment," appendix C, deals directly with the situation you are faced with, and goes through a number of steps for 'do it yourself' recovery from smoke and water.
In addition, there are dozens of local and regional businesses that deal with this sort of restoration project. If it turns out you feel the damage and/or work is too great to take on yourself, I would advise looking into "Fire restoration" companies locally. A few moments with a web search or web-powered yellow pages application should get you in touch with several locally. One benefit to a professional restoration program is that if local authorities (environmental and/or occupational safety groups) are required, they will have experience in finding the right folks to get in touch with.
This was first published in July 2005