Exhaust Heat Pump: Why are my bill's so high?

The first couple of days I lived in the flat I noticed the bills were incredibly high. Someone, who helps building the flats, told me the immersion was on and that was why things were high. So, since then, I’ve always had that turned off. So not sure it’s that.

Before I switched the temperature to a consistent one throughout the day, I did notice spikes at 7.30am and 6pm (the times I had the temperature to go up). Ironically though, the usage now is the same as then :)

The plot thickens !!

Can you try a comparison for a 24 hour period - switch the immersion back on and see what your half hourly graph shows. If we compare a non immersion period with that (preferably with similar weather conditions which we do have for another day or so) it might give a hint as to what’s going on.

Personally I wouldn’t have the meter checked just yet as I don’t think that’s responsible for these peaks.

I’ve just had someone from the estate agents come over to take a look at things. She is quite new to heat pumps too so didn;t know loads. But I showed her the usage I’ve had the last month, including the nutty £12 day. She did actually mention that the property management team suggested, at the very start, for tenants to have the immersion on all the time. That surely would cost loads?! Anyway, I’ve put it on and let’s see what that does to the price for the rest of today.

It should just be switched on and off by the control unit so won’t actually be drawing power all the time 🤞🏻

So just to clarify, the switch for immersion is on but the heat pump controller will decide whether to actually power it up if it’s needed. 
This is mine:

Switch top right is On but red indicator light is only lit when the heat pump  chooses to use it. Ignore loose cable marked “immersion backup” hanging alongside !!

Evening ​@joshantmann just wondering how you’re getting on with the latest change ie having the immersion switch on? I’m just listening to a podcast about ventilation systems (yes really 🤦‍♀️) and the ducting you have on yours was described as the least good as it falls into kinks and the corrugations tend to trap moisture. It would be far better if it was solid insulated ducting. I think from what you’ve said that you’re renting so I’m not sure what you can do about that, but it does make me wonder what the ducting we can’t see is like.

​@joshantmann not heard from you for a few days but I’m still very interested to know how your system is doing.

Apologies for the very late reply. Still having a few issues with the heatpump and I can’t work out what is going on. The property management team are really not helping me at all and I’m having to do everything myself. I can;t even get into the advanced settings, to try and adjust the hot water, as the property management have no idea what the code is and won’t get an electrician around.

Anyway. Here’s a general example of my usage. This was from the Monday just gone and I actually left my flat for 24 hours at 3pm and turned off my thermostat...you should be able to see that. By the way...I have my thermostat on a schedule in 4 parts, 7.30am-9am (18c), 9am-6pm (15c), 6pm-10pm (18c), 10pm-7.30am (15c). So I can’t work out why there is movement at 4.30am for a couple of hours. In addition there is more movement at 5pm, for 3 hours when the heating isn’t even on!

The immersion hasn’t been on at all and there is nothing else on in the flat. So if anyone has a clue as to what is going on then I’d love to know. Thanks all.

Hi ​@joshantmann When you say the immersion hasn’t been on at all is that because you’ve turned it off somewhere?

My advice is to leave it switched on so it can be controlled by your Joule system.