Long update from your neighbour…
I sent a documented case to the Norwegian consumer authorities in April after the seller refused to cooperate and made unreasonable demands when I asked to switch to another brand through him (eg. Not allowed to reference any measurements towards the service manual, just have to accept that it will be «as is» etc, seller couldnt even provide me with any information about what a proper replacement could be).
It took about 6½ months for the case to be officially opened. The same evening the case was assigned to a caseworker, I suddenly received an email from the seller saying that Panasonic wanted to buy the unit back. I sent my «report» to Panasonic as well, without any replies.
Apparently, asking questions about marketing numbers that are not achievable and about poorly programmed control logic was too much…
I'm now getting the pump removed and will receive a full refund. I'm happy with the outcome, but I'll stay clear of Panasonic heat pumps in the future unless they make major improvements in several areas:
Technical and functional issues
- Defrost time (15–25 minutes) – The pump can take up to 25 minutes before it starts blowing warm air again, but usually 20 minutes. For homes with larger heating demand, this can create a negative cycle: as the temperature drops after each defrost, the unit ramps up unnecessarily, which in turn causes more frequent defrosts.
- Temperature readings after defrost – After defrost, the unit blasts hot air for a short time, then short-cycles aggressively. Which in turn causes defrosts to happen more often.
- Temperature control – When the display shows 21 °C, increasing the setpoint to 21.5 °C or 22 °C does nothing, same energy use, same air temperature. Only at 22.5–23 °C does it react, but then it overshoots and wastes power.
This leads to confusing temperature behavior: 21 °C might keep the house at 22 °C one day, but when outdoor temperature changes, the unit doesn't adjust its power draw so indoor temperature slowly drops or rises even as the unit "thinks" it's stable.
From the service manual, it looks like the unit only reacts to temperature differences larger than 1.5 °C, which might explain the strange behavior. (My wife said it was cold, so she increased the temp by 0.5 like with the mitsu, nothing was happening, then another 0.5. Still nothing and she was cold. Then after doing this a few times it was suddenly way too hot. Not very user friendly)
- Internal temperature sensor placement. From the factory, it's mounted directly on the indoor coil. This design caused huge temperature fluctuations and unreliable readings in my case.
- Minimum input power draw. The marketed minimum power draw is not achievable under normal conditions. The seller had no idea how to make it happen, and Panasonic hasn't commented either.
Looking at other forums (and as I wrote previously here) found a hidden "recipe" for achieving the advertised numbers, but it's basically impossible unless the internal sensor is moved far away from the coil. My unit had, on the worst days, up to 100 starts/stops per day, causing big indoor temperature swings and unnecessary power draw due to this.
Other issues:
- Ticking sound: A mechanical ticking noise started around 7–8 months in. Before buying, I was told "there are never issues with Panasonic," yet the seller's later email suggested this was actually a known issue with a bearing and an adjustment needed.
- Outdoor unit behavior: The first outdoor unit defrosted without any real need for it. Replacing the unit improved this, but it still performs unnecessary defrosts even with a clean coil, just less often.
- Noise level: The outdoor unit is much louder than my previous Mitsubishi and Daikin models. It genuinely sounds like a small propeller plane, and the compressor makes a metallic resonance.
- Indoor vanes: The vanes on the indoor unit deformed after only 2–3 months of normal use.
Summary:
I'm relieved to get a full refund, but the experience was exhausting. The product clearly doesn't perform according to its specifications, and the support process was unnecessarily difficult. Hopefully this helps others evaluate their options before buying.
Unit will be replaced with a Daikin comfora we have in the bedroom, which I know works fine…
Disclaimer: These are my personal experiences with «one» unit and one seller; others may have different results.