No, looking back over it now it does appear that it is a water loop that goes between a heat exchanger in the outdoor unit and the storage tank. Glad you pointed this out to me before I ordered this for myself .
That does seem like a weird way to set it up. Why not have the heat exchanger indoors on top of the tank and run a refrigerant that can't freeze all the way there? I guess I'd know if I was an engineer, or had an engineer explain it to me.
You probably saw the Freeze Protection bullet points. It does reference some kind of freeze protection heater. That seems strange, as the entire unit is a heater that is supposed to work effectively at temperatures as low as -20F. It should be able to sense when the outside temperature is below freezing and just run the system slowly to keep the water moving, which should keep it from freezing. I wonder if there is a backup heater in the outdoor unit for cold snaps where the temperature might be below spec?
Or perhaps -20F is just the threshold for where you'll be able to get the hot water like you want, but perhaps it can still (with an efficiency penalty) pick up heat at lower temperatures without getting the water as hot as you want, but still well above freezing.
That does seem like a weird way to set it up. Why not have the heat exchanger indoors on top of the tank and run a refrigerant that can't freeze all the way there? I guess I'd know if I was an engineer, or had an engineer explain it to me.
You probably saw the Freeze Protection bullet points. It does reference some kind of freeze protection heater. That seems strange, as the entire unit is a heater that is supposed to work effectively at temperatures as low as -20F. It should be able to sense when the outside temperature is below freezing and just run the system slowly to keep the water moving, which should keep it from freezing. I wonder if there is a backup heater in the outdoor unit for cold snaps where the temperature might be below spec?
Or perhaps -20F is just the threshold for where you'll be able to get the hot water like you want, but perhaps it can still (with an efficiency penalty) pick up heat at lower temperatures without getting the water as hot as you want, but still well above freezing.