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Posted by: @editor@andrewj it appears that Microsoft email address (including Hotmail and Outlook) are blocking some of our system issued notifications as spam. Please try and whitelist emails from "renewableheatinghub.co.uk" as not spam.
Must be a recent thing. I've added this to my safe senders and will see how that goes. MS do some strange things with their Spam/Junk filtering: they run their filters and make a decision for you before you even get to know about it, so it's not possible to, for example, set up mail rules because they have also decided that mail rules should never be run on mail going to Junk!
If you reply to this I'll see if it works or not.
Think of it like a dT modulated unit. Since they can offer a tarrifs into a specific unit with say a oversize compressor, it does make sense to aim at running cost rather than scop... So as backwards as it sounds it might be cost beneficial to bump a cosy off it's minimum 24/7 schedule (they really don't like running below 34C) and dumping heat when it's cheap 3x a day at a marginally lower COP.
If you have a battery, the cost effectiveness of that storage will really trump any tiny scope gain also...
@pwils on the cosy hub, there’s a button on the top, press and hold it for several seconds, the cosy white light will flash blue and you can link your phone to it via blu tooth.
You can then login to the hub at 192.168.1.1 and view lots of parameters; anything you can’t view or alter is protected so have a furkle.
Last night I set the schedule to be 25c 24/7, a temp it can't reach so it is now running continuously. Looking at the sparse data available to me, I can see that I used an average of 1.02kW (min 0.91kW, max 1.17kW) per hour with an OAT between 6.0c and 4.1c, excluding the water heating period. My main living area stayed between 22.2c and 22.4c. A couple of rooms downstairs were at 19.8 at 7am (LSVs on these fully open.) Upstairs temps ranged from 23.7c to 25.5c. I know this isn't wholly relevant but reported COP is 3.91.
I'm looking to run at around 22c so my thought is that the WC curve looks about right and I should just turn down the LSVs on rads upstairs (a total of 6 rads) and tweak down 2 rads downstairs which are over heating - I have 15 rads in the house in total. I could then come back to the WC curve if the living area is getting too warm.
As earlier, does the power consumption feel about right for this OAT? I have no historical data to go on but from an earlier post it would seem that the answer is yes.
Posted by: @andrewjAs earlier, does the power consumption feel about right for this OAT? I have no historical data to go on but from an earlier post it would seem that the answer is yes.
Depending on your house loss and location I would say probably yes.
Here is what my 7kW Vaillant has been doing, and the OAT. My house loss is 7kW @-2
Posted by: @andrewjI'm looking to run at around 22c so my thought is that the WC curve looks about right and I should just turn down the LSVs on rads upstairs (a total of 6 rads) and tweak down 2 rads downstairs which are over heating - I have 15 rads in the house in total. I could then come back to the WC curve if the living area is getting too warm.
Sounds about right. When balancing radiators (which you are obviously still doing) at least one LSV should normally be fully open, there is no point in artificially restricting flow.
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
@jamespa Thanks James. The temps are crazy upstairs - it's hitting 26c on the landing. I've closed down all upstairs and then cracked it open 0.25 turns to see how that goes. I have two radiators downstairs fully open, in the coldest rooms. Living area downstairs has hit 23c with an OAT of 4.9c but I don't know if it's due to solar gain or not - my house is a Finnish style one so the soffits are really large (for snow fall presumably) so the sun doesn't directly shine in - and it's West facing. It may be worthwhile turning down the WC 0.5c and seeing if that impacts things - it doesn't matter too much if it cools down below 22c overnight as I want to try and sneak us to 21c anyway (don't tell the wife 🙂 )
Posted by: @andrewj@jamespa Thanks James. The temps are crazy upstairs - it's hitting 26c on the landing. I've closed down all upstairs and then cracked it open 0.25 turns to see how that goes. I have two radiators downstairs fully open, in the coldest rooms. Living area downstairs has hit 23c with an OAT of 4.9c but I don't know if it's due to solar gain or not - my house is a Finnish style one so the soffits are really large (for snow fall presumably) so the sun doesn't directly shine in - and it's West facing. It may be worthwhile turning down the WC 0.5c and seeing if that impacts things - it doesn't matter too much if it cools down below 22c overnight as I want to try and sneak us to 21c anyway (don't tell the wife 🙂 )
Some tweaks of WC may indeed be necessary, if its too hot both downstairs and up (and its not solar gain) then you definitely need to turn the WC down!
Hot upstairs seems to be a problem with modern houses. With open plan and good insulation, there is literally nowhere for the heat from downstairs to go other than the bedrooms. People on buildhub are now doing newbuilds without upstairs heating other than in the bathroom. This is all a bit iterative, it might take you the whole season to get it spot on. There is also an element of adjusting to constant temperature!
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
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