@webcmg Glad to help. If you only charge up the cylinder once at night and you might be able to save a little more. Something doesn't seem quite right as our consumption is less than half of yours, 30kwH vs 71kwH so far this month but you may use the hot water much more than us (family of 4 with 2 small kids).
@colin Hi Colin, we've certainly reduced our Kwh usage for the hot water based on the settings. We now currently use between 3-4 Kwh per day to heat the water. 2kwh in the morning and 1-2kwh in the afternoon depending on usage (n.b. flat rate tariff). The anti legionnela cycle seemed to reach the required temperature when I checked this week which is also good. Thanks for your help.
Interesting, I'd like to get to the bottom of the efficency because we're seeing high usage for DHW and heating which is why I started this thread. I did insulate the cylinder (which sits outside the thermal envelope of the house in a store room area of the garage) on 5th June and this seems to have had a minor impact (although it could also be the warm weather). This and recharging twice per day will accounts for some of the difference (up to 18 kwh?) .
In terms of usage, we are a couple without kids and we each have a shower per day, one of us in morning and the other at night. My wife does seem to like having long hot showers and we have large high capacity rainfall shower heads. I suspect this could be a factor. If I have a relatively quick shower in the morning the cylinder temp drop off is around 10-15 degrees, so the cylinder does normally need recharging during the day to avoid a disappionted wife.
A few questions, if I may?
Do you all have showers at a similar time of day?
What style showers do you have?
What is the orientation of your heat pump unit (ours faces westerly) - pictures of installation would be helpful if possible?
I thought a recharge during the day might result in a higher yield ad the air temperature is typically higher, is this likely to make a difference?
Is anyone aware of any other reasons why our heat pump might not be acting efficiently?
@colin one thing I have noticed is that we have a secondary return on the hot water circuit. It has a timer which activates a pump to circulate the water. This is to reduce the hot water run off time in the extremities of the property. I haven't ever switched the pump timer on do the pump isn't active but I have noticed that the pipework on the return is often very hot. Could it be convecting/syphoning which means the water temperature is reducing more quickly thank normal?
@webcmg We don't have showers at a regular time each day, also we have the same style showers as you. Our pump is pointing in an east-north-east direction. Recharge during the night will consume a little more because it's cooler outside but that's when our tariff is 3 times less so makes sense in our case.
Your cylinder could be heating up multiple times per day because of usage which may explain the higher consumption? If you can figure out if your 300L cylinder only consumes 2 to 3kwh to do a single recharge, if not then there's something not right. Easiest way would be set it to charge for a couple of hours each day. Ours only takes about an hour to charge up the 300L tank, even in winter.
I'm not sure if I've got the circulation pump. I've included a graph of my cylinder temperature over the past few days so maybe you can compare temperature loss etc during the day.
@webcmg Hi, I'm using a free bit of software called 'Home Assistant' that can run on almost anything including old PCs. link: www.home-assistant.io/
I'm using the below Home Assistant Vaillant integration to monitor the all the Vaillant kit, Pump/Cylinder/Controls.
Link: github.com/thomasgermain/vaillant-component
It's helped me a lot by getting a bit more understanding about what was happening under the hood and optimising our consumption but I appreciate it needs a wee bit of technical know how.
@webcmg Hi, I'm using a free bit of software called 'Home Assistant' that can run on almost anything including old PCs. link: www.home-assistant.io/
I'm using the below Home Assistant Vaillant integration to monitor the all the Vaillant kit, Pump/Cylinder/Controls.
Link: github.com/thomasgermain/vaillant-component
It's helped me a lot by getting a bit more understanding about what was happening under the hood and optimising our consumption but I appreciate it needs a wee bit of technical know how.
Thanks, will have a go at getting this set up. Hope it works with the installation here.
There're other ways that don't rely on IHDs, e.g. I'd bought a SMETS2 monitor which also works well but you need to buy the monitor plus a Zigbee dongle/controller. www.amazon.co.uk/gp/product/B08WXT6HHJ
These dashboards helps me to see what's going on under the hood at a glance.
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