調べてみたらこいうことらしいです↓
http://www.content4reprint.com/business/home-business/network-marketing/warm-marketing-vs-cold-marketing.htm
A "warm" contact is someone we have previously dealt with - ie. someone with whom we have built a rapport , or gained their trust in the past. People in this group range from family and friends, to colleagues, past clients, etc. Basically, anyone you know (and who knows you back) could be considered a warm contact.
On the other hand, a cold contact is simply the opposite of the above. We have not met these people, and hence do not know their behavioural or consumptive patterns, nor their real demand for our product.
端的に言うと”Warm”はリピーターもしくは取引きしたことのある顧客で、対して後者は新規顧客ということですね。
推察するに仕事の内容は、Res1さんがおっしゃるように、新規飛び込み営業といったところではないでしょうか?Cold Callは新規開拓を電話で行うということです。