If you are losing coolant and once it gets low enough then the heater core will lose coolant as well and could lose heat. I would suggest to keep the coolant topped off to start but we need to confirm why you are losing coolant.
https://www.2carpros.com/articles/head-gasket-blown-test
I would suggest to test the head gasket and make sure that is the issue and then we will need to repair that, fill the coolant and retest the heat.
Let me know what you find with the head gaskets and we can go from there.
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Thursday, November 12th, 2020 AT 1:04 PM