The phrase putting out fires means dealing with many small problems, usually at work. Though the problems might be small, they need to be solved quickly before they become bigger ones.

Take note

To get on like a house on fire. If you say two people get on like a house on fire, it means they like each other and find it very easy to become friends – they get on very well together.

Example:

Phoebe and Alice get on like a house on fire. They share exactly the same sense of humour and are always joking and laughing together.