This might be part of a bigger temperature overhaul (big rooms + fire is a "bit" broken combination), but with the addition of that new low tech cooling device, this might show up sooner.
Long story short, I feel colonists and animals should produce warmth, as seeking warmth in each other and dogs are probably the oldest methods to combat cold.
To avoid CPU overload in an attempt to track every entitys heat effect, this should only "switch on" while sleeping (as it's the most relevant then).
To rebalance low tech heating, pawns would get negative thoughts when sleeping in a room with fireplace (smoke etc.), you could avoid this by venting heat from separate "broiler room" with airvents.
Long story short, I feel colonists and animals should produce warmth, as seeking warmth in each other and dogs are probably the oldest methods to combat cold.
To avoid CPU overload in an attempt to track every entitys heat effect, this should only "switch on" while sleeping (as it's the most relevant then).
To rebalance low tech heating, pawns would get negative thoughts when sleeping in a room with fireplace (smoke etc.), you could avoid this by venting heat from separate "broiler room" with airvents.