S2D2

100% sink in the middle

Did they specify a flow temp? They proposed ripping out and replacing all my rads to hit a flow temp of 50 and would not allow me to spec larger radiators at my own cost. I raised it with the heat pump team and greg@octopus who just referred it back to the heat pump team. They claim that they design for a scop of 3.3 with an "efficient" flow temp of 50 because 3.1 would cost the same to run as a gas boiler. This year the average Octopus tracker scop needed for price parity is around 3.7, so they're openly talking absolute nonsense. Quoted 5.5k after the 7.5k grant, so not even worth accepting then doing the rads myself later. I was on here touting them as a good option before I hit this brick wall with them.

Octopus refused to design rads for a flow temperature below 50°C for me so they're a non-starter for homes that can (and should) go lower. Smaller local MCS outfit has been much more accommodating.

Don't expect the 15p rate to be around for a lot longer, tracker import is down to around 17p.

I don't understand the price of these things, you could pay a human to do it for about four years for that, how long is the warranty?

Yes, Vaillant I think use a MID approved electricity meter but the MID approved heat meters are very expensive so they use cheaper sensors to calculate flow rate and flow/return temp. Generally regarded as accurate enough, some other manufacturers have been shown to be way off.

Arotherm plus? They're known for outperforming the datasheets when installed well. You're a bit above the crowd at https://heatpumpmonitor.org/ but it depends if your plumber was just rounding up and you will be running at a lower flow temp etc.

The upgrades part of the site is for an ASHP Install quote, if you just want information from their articles try https://www.heatgeek.com/category/knowledge/ or their YouTube channel https://youtube.com/@HeatGeek

I could be wrong, but I think this is the same change that has been in place for new signups since December, so if you signed up recently there won't be an extra increase. They're now moving old signups which weren't a fixed term tariff (which the new one is) to the new rates.

Octopus Tracker has had by far the best rates over the last year. Obviously it's not without risk as prices change daily but as long as the market is on a downward trend it should be a winner.

In hindsight, Cosy worked well but ended up costing £30 more than just being on Octopus Tracker for 3 months, before even factoring in battery inefficiencies. So I'm just on Tracker now. Obviously tracker won't stay cheaper forever, but at present with low rates on Tracker there just isn't a use case for Cosy to me. It still compares well against standard variable, of course. Flux was a different beast, over £200 better being on that over summer compared to Tracker with fixed export at 15p, so I'll switch back to that again in the spring depending on where export rates go.

Zero and 3 will behave the same (full OS with Python on top). CircuitPython is for things like the Pico. Good luck.

adafruit_mlx90614 is the CircuitPython library (https://docs.circuitpython.org/projects/mlx90614/en/latest/api.html) so you'd have to flash the firmware to your microcontroller. I'm assuming instead you're using a zero or such with a standard python install, so you'd want another library. The one you linked might work but note the different name for pip/include: https://pypi.org/project/PyMLX90614/ Full disclaimer I've never used any of this stuff so could be completely wrong.

Adtran box will be the ONT probably, Linksys modem+router. It should have spare ethernet ports in the back, if so you don't need a switch?

Tracker is a daily price. Agile has half-hourly pricing that varies over the day. Both have their rates set the day before or so.