4 ms·

If you have floor heating + heat pump, then the manufacturer recommendation is to keep it running 24/7 from October to April. That's for the climate where I liv

• lucb1e 5y ago
  Why though? Is it to not have disappointed customers because it takes 4 hours to heat up and it's harder to explain to people how to set a timer to turn on at 3am, or because keeping a higher temperature delta between indoors and outdoors is actually more efficient with this system?
  • genewitch 5y ago
    I'd wager it's to prevent damage if the stuff inside the pipes freezes/expands.
    • lucb1e 5y ago
      Floor heating won't go from heating temperatures (30°C? I don't know exactly) to freezing across 8 hours of sleep, even if it's -25°C outside. The advice also doesn't have to be "turn it off", just "turn it down to 5°C" which would be safe indefinitely. There has to be another reason why the advice is to keep heating 24/7.
      • jan_g 5y ago
        The controls available aren't in the sense of thermostats - for example, you can't ask it to keep temperature at 21 degrees during the day and 18 degrees during the night. Instead, it has something called 'heating profiles'. There are summer (passive cooling, essentially) and winter profile (heating). And for the winter profile you can set the level of heating: from -5 to +5 degrees compared to what it considers optimal. I have mine always set to -5, because even at that setting it's warm enough. Note that 'degrees' in this instance is not the air temperature in the rooms, but I believe the water temperature in the pipes. In other words, it will automatically adjust depending on the time of day, temperature outside, etc. It is possible to influence how it works, via 'administrator' settings meant for the repair guys, but I haven't touched those.
        • IshKebab 5y ago
          Well that just sounds like a badly designed heating system then.
          • mercutio2 5y ago
            I have radiant floor heating, and setting the thermostat to my target temperature 3 hours before wake-up is fine. But note that the OP has not just radiant floors, but also a heat pump (which isn’t using gas, so we’re far afield from the overall question, but setting that aside). Heat pump systems are generally sized so that compressor’s sweet spot is pretty close to your expected normal/max output. To be honest, this is more about the lifespan of the compressor than it is energy efficiency, but there is also a small loss of efficiency if you get the system into a state where it’s turning on/off frequently. So it seems plausible and sensible that a radiant-heat pump system would recommend circulating 24/7 in the winter rather than cycling on/off a lot.
          • jan_g 5y ago
            I don't know. It's not what I was used to before in my previous homes (thermostats in different rooms, specific temperature settings, etc.), but you know what? It keeps me warm and is cheapest heating I've ever had to pay for, by far.
  • jan_g 5y ago
    I don't know all the details and reasons, because I don't have enough knowledge about heat pumps. But the explanation given was that takes many hours for the whole system to 'warm up' and start working within optimal range. Turning it on and off frequently would actually make it perform worse, wasting more energy than if it's running all the time.