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Hi Derek,
What I changed this morning has made the ufh come up to temperature very quickly, so I'm guessing that's not going to be efficient as the thermostats have knocked it off again. Prior to me messing it seemed slow and steady.
Unfortunately time is one thing I have little time to adjust, and tbh my patience is running rather thin after 3 years for what I was hoping would be set up on commissioning by a company that sells such products.
This kind of aggravation is what puts people off ashp's. Can't remember having such issue's/set up with a gas guzzler.
2102 is set to 34c now but guess I need to lower again. Or change something that I already did this morning?
Posted by: @roamingbullHi Derek,
What I changed this morning has made the ufh come up to temperature very quickly, so I'm guessing that's not going to be efficient as the thermostats have knocked it off again. Prior to me messing it seemed slow and steady.
Unfortunately time is one thing I have little time to adjust, and tbh my patience is running rather thin after 3 years for what I was hoping would be set up on commissioning by a company that sells such products.
This kind of aggravation is what puts people off ashp's. Can't remember having such issue's/set up with a gas guzzler.
2102 is set to 34c now but guess I need to lower again. Or change something that I already did this morning?
Changing 2104 from 0C to -5C will automatically reduce the required LWT.
I presume when you say it was "slow and steady", this was during milder weather conditions. The problem now would appear to be that as the weather gets colder, a LWT of 35C is insufficient to supply the heating demand, due to the increased heat loss.
The reason that many installer try to avoid correctly adjusting the WC curve is because it can be time consuming.
You don't need to spend all day monitoring your system, particularly if historical data is available. Once correctly optimised it should not be necessary to make further adjustments to the WC curve.
Obviously it is your decision as to how much time and effort you wish to spend getting the settings correct.
Good Evening Derek & AF,
Sorry for the late reply to your info given.
So I change the settings as per AF/Grants settings a few days back.
Outcome is that I have reduced 2102 down to 30.5c and nothing really has changed and it's still staying rather warm.
2101 = 45c but that shouldn't make any difference as we are on WC.
2102 = 30.5c and it's staying around 22c given that I've dropped it 4c!!
2103 = 30c
2104 = 0c as per AF's reply.
2105 = 20c. All these are more or less Grants figures.
Heating the 300m2 house with the fairly mild weather is just under 30kw per day fyi.
Posted by: @roamingbullGood Evening Derek & AF,
Sorry for the late reply to your info given.
So I change the settings as per AF/Grants settings a few days back.
Outcome is that I have reduced 2102 down to 30.5c and nothing really has changed and it's still staying rather warm.
2101 = 45c but that shouldn't make any difference as we are on WC.
2102 = 30.5c and it's staying around 22c given that I've dropped it 4c!!
2103 = 30c
2104 = 0c as per AF's reply.
2105 = 20c. All these are more or less Grants figures.
Heating the 300m2 house with the fairly mild weather is just under 30kw per day fyi.
Try lowering 2103.
So more or less step forward Two weeks to -2 temperatures and we are struggling to get 20c. Increased 2102 back to 35c. But still struggling.
Guess the only option is to increase 2102?
Can anyone tell me how I would check that Weather Comp is enabled on my system? I can’t seem to find that out anywhere.
I remember when I asked the installers if it was enabled they were like “yeah, sure”. I wasn’t convinced.
Grant couldn't make it any simpler(!) ... or not ...
Go to the Controller, and open up the flap:
Press 3 buttons at the same time: the one that looks like the sun (top row), and + and - (2nd row) Hold them down for a count of 5 (at least) until you hear a bleep, then release.
The display should now show 'Inst' with '00 00' below it, and one of those '00' will be flashing.
To change which '00' is flashing, press the + and - keys. To change the flashing value use the up/down arrow keys on the right of the controller.
You want the value to be '21 00', so that's either 21 keys presses, or press and hold the up arrow for a while when the left most '00' is flashing.
Once you have '21 00' flashing, press the 'tick' button. This will then show the value for '21 00'. If it's '1' Weather Compensation is on; if '0' then it's not.
I'm not sure this user interface is going to be widely adopted.
Grant Aerona 3 10kW
Posted by: @marvinator80Can anyone tell me how I would check that Weather Comp is enabled on my system? I can’t seem to find that out anywhere.
I remember when I asked the installers if it was enabled they were like “yeah, sure”. I wasn’t convinced.
To do that one needs to know what system you have.
Retrofitted 11.2kw Mitsubishi Ecodan to new radiators commissioned November 2021.
14 x 500w Monocrystalline solar panels.
2 ESS Smile G3 10.1 batteries.
ESS Smile G3 5kw inverter.
@roamingbull or disable weather compensation for a short period and revert to constant higher flow temperature. My 10kW Aerona is defrosting every 45 minutes or so, and as a result is not reaching target leaving water temperature. It should be 45degC at 0degC but it’s about 41. Still doing the job, but the house is a couple of degC cooler as a consequence. Log burner had just been lit to boost for the evening….
thanks Mike.
going through the 2100s now.
weather comp is on.
2101 55 degrees
2102 52 degrees
2103 35 degrees
2104 -4 degrees
2105 30 degrees
Anything look off to you or anyone else from that?
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