Hi, I had an R290 Ecodan 6kW (with a 200l FTC7 packaged cylinder) installed at the end of August.
I’m hoping to get Level 2 monitoring installed later this year or early next year. I have a Shelly EM monitoring the power usage at the moment, I am using Phil Thomson’s Ecodan esp8266 WiFi bridge to monitor and control it via Home Assistant, which has been very useful as I don’t have a wireless FTC controller.
I’ve been quite impressed with it so far, a COP of roughly 3 (calculated from the Ecodan outputs) during some mild weather periods in the North West of Scotland (Isle of Lewis).
The Ecodan seems to overestimate consumption by about 50% compared with the Shelly data, the longer the run time, the less the consumption overestimation seems to be. If I take the Ecodan production values and the Shelly measured input the COP is closer to 4.5 on average.
The pump has barely used the immersion even with 60C legionella cycles.
A R290 heat pump should never use the immersion, R290 can deliver a flow temperature of 75C. It’s debatable if legionella cycles are required at all, but 55C-60C tank temperature is plenty hot enough to kill legionella
My immersion has been used for about 15 minutes since install over 100+ days, at the high point of the legionella cycle when it is nearing ~60C, it doesn’t always but it is usually between 3-4 minutes each time.
I think the R290 Ecodans were launched at the end of 2023, I think only in the last couple of months they widened the range to their larger units (above 8kW). To be honest with the lower advertised COPs I can understand the limited uptake and in retrospect my installation would have been simpler with an R32 and a preplumbed (as opposed to packaged) FTC6 cylinder with MelCloud, as my installer hadn’t installed an R290 one previously and there seemed to be some confusion in what parts were required from the wholesaler.
Not sure if there are any other benefits to R290/FTC7 (aside from the high temp performance), I’m impressed with how low it can modulate, it’ll be interesting to compare it with an 8.5kW R32 my mother will have installed next week by the same installer.
Vaillant’s R290 units also uses the immersion/backup heater for the Legionella cycle. 75°C flow does not translate to 70+°C DHW temperature, which is what they are targeting (irrespective of whether that makes sense).
