That is a good question. On my Forest River I never had a problem and I did camp in freezing temps. In that coach the outdoor kitchen was located next to the compartment with the water pump and whole house filter and that compartment was heated.
My Challenger has heated storage compartments where the water tanks, filter and pump are located. I honesty don't know about the outdoor kitchen area. I am on a business trip about 500 miles from the coach so I'll have to pull the outdoor kitchen drawers and look around inside this weekend.
Is there a specific coach model that you are asking about?
US Army (Ret)
2020 Entegra Accolade 37TS
2019 Jeep Grand Cherokee Trailhawk (Toad)
FMCA - F432054