This symbol is a combination of the ideograph for the noun tent and a pictograph of some flames. An open-air fire that is associated with tents is a campfire.
Illustrative Text Reference:
Harappa: Tablet in bas-relief: H-766 A: Sayid Ghulam Mustafa Shah and Asko Parpola, 1991: Corpus of Indus Seals and Inscriptions: Volume 2: Page 323: Collections in Pakistan: Suomalainen
There is only one extant example of this Indus sign.
Indus Script Sign Number 4359: List of Sign Variants: Iravatham Mahadevan, 1977: The Indus Script: Texts, Concordance and Tables: The Director General Archaeological Survey of India.