Hello everyone. Our air-to-water heat pump has been in use for about half a year now. We recently noticed some hissing noises coming from the outdoor unit. It sounds similar to a truck brake losing pressure, but somewhat quieter. I have heard this noise three times so far. The last time, I happened to be outside near the outdoor unit. The noise appeared, and the fan stopped running—not suddenly, but gradually. I stood right in front of the unit to see what was happening. After a few seconds, the fan turned on again. At that moment, a kind of "cloud" appeared. Not a real cloud, more like when you blow dust off an old book. It didn’t smell like something burning, but more like intense heat being generated. I hope you understand what I mean. How would you assess this situation? So far, neither the heating system nor the unit has shown any error messages. The heating is working perfectly. Because of the weather, the outdoor unit is practically running almost non-stop. Could this be some kind of overheating that causes the fan to briefly switch off?
untergasse437 Jan 2021 18:23In summer, I would use it to heat the pool 🙂
I was a bit startled the first time I watched our air-to-water heat pump during the defrost cycle.
By the way, I just checked the heat balance. Out of 8,703 kWh (thermal) produced, 245 kWh (thermal) were used for the defrost process. So, over 6 months, that caused about 15€ in electricity costs. That’s negligible 🙄
By the way, I just checked the heat balance. Out of 8,703 kWh (thermal) produced, 245 kWh (thermal) were used for the defrost process. So, over 6 months, that caused about 15€ in electricity costs. That’s negligible 🙄