Weather Compensation Cost not efficiency?
Posted by: @jeegneshso this is on Valiant aroTHERM and my settings has the the room temp mod now set to inactive, so essentially no thermostat, hence my question what the timer is for
The timer is for if you are in expanded mode the wc is modified by switching off the heating if it’s too warm. You can have a set-back temp overnight or other period with a lower temperature for a certain time.
The other mode is active which is wc plus aiming to a set temperature (ie like ‘normal’) and that is for certain times.
2kW + Growatt & 4kW +Sunnyboy PV on south-facing roof Solar thermal. 9.5kWh Givenergy battery with AC3. MVHR. Vaillant 7kW ASHP (very pleased with it) open system operating on WC
If I am in inactive mode, then how or when does setback kick in?
Timer mode lets you specify a time and a temperature but as inactive the temperature for sure has no input.
13.6kw Solar, 27kw Battery, 10kw Heat Pump and EV Car
@jeegnesh Doesn’t matter which room temp mod mode you’re using; the following behaviour happens:
During scheduled ‘heating’ periods, the heat pump targets your chosen set point temp.
During scheduled ‘off’ periods, it targets your chosen setback temp.
So this is it, what is my chosen set point, how does it get that? Considering the Room Temp Mod explanation and mine is set to Inactive.
-
InactiveThe thermostat is only a display, and the heating circuit is not being used
-
ActiveThe thermostat adjusts the flow temperature based on the difference between the room temperature and the indoor target. For example, if the room needs more heat, the system will increase the flow temperature.
-
ExpandedThe thermostat acts as an on/off switch for the heating, turning it off if the room temperature is exceeded. The system control also regulates to the target room temperature, regardless of the outdoor temperature.
13.6kw Solar, 27kw Battery, 10kw Heat Pump and EV Car
@jeegnesh Your chosen set point temp is the desired indoor temperature that you choose via your SensoCOMFORT controller and myVaillant app.
If you’re finding that your house doesn’t drop in temp enough to hit your chosen setback temp during the scheduled ‘off’ period, then this means that either your weather comp curve needs tweaking, and/or you should select a lower setback temp.
@ectoplasmosis so it constantly breaches that number and turns on.
I do know if I switch to expanded then it adheres to that temperature. So I guess I am asking what inactive does
13.6kw Solar, 27kw Battery, 10kw Heat Pump and EV Car
@jeegnesh It’s all been explained to you already.
Inactive is pure weather compensation mode, where the only sensor which affects flow temperature and thus heat input into your house is the outdoor temp sensor. There is no longer a concept of an indoor thermostat.
If your system is overshooting your chosen set point temperature, then your weather compensation heat curve setting is set too high. Lower this setting, wait a couple of days and see how your house reacts. This is a process of trial and error, and takes time to end up with the perfect curve setting which suits your particular house.
Make sure any TRVs etc are fully open.
@ectoplasmosis perfect this now makes total sense to me.
13.6kw Solar, 27kw Battery, 10kw Heat Pump and EV Car
- 26 Forums
- 2,242 Topics
- 49.9 K Posts
- 365 Online
- 5,903 Members
Join Us!
Podcast Picks
Latest Posts
-
RE: My experience with 3 heat pump surveys: Heat Geek, British Gas & Octopus
Did they confirm it was being installed as an actual 4 ...
By Temperature_Gradient , 38 minutes ago
-
RE: Daikin Octopus installation update - I saw my first defrost. 😍😂
@radwhisperer Thanks but that is definitely not a mixer...
By Jancold , 44 minutes ago
-
-
RE: RDSAP10 effect on existing heat pump EPC rating?
As I understand the situation, Elmhurst Energy trains e...
By Transparent , 5 hours ago
-
RE: Octopus Cosy Heat Pump Owners & Discussion Thread
OK thats cheap, the commercial price seems to be £400 p...
By JamesPa , 6 hours ago
-
RE: Solar inverters - where does the energy go when clipping?
I think I must query the sources on which Greenmatch ha...
By Transparent , 8 hours ago
-
RE: Replacing knackered oil boiler with Samsung ASHP - Perthshire
This is how I run my Samsung 12kW ASHP with a 3rd party...
By Old_Scientist , 10 hours ago
-
RE: Testing new controls/monitoring for Midea Clone ASHP
@cathoderay thanks- yes will keep an eye out for the de...
By benson , 1 day ago
-
RE: Renewables & Heat Pumps in the News
Hoping so as well! I am no specialist. The language use...
By Batpred , 1 day ago
-
Do you need the DHW tank as high as 50°C @egp01 ? Ha...
By Transparent , 1 day ago
-
RE: The Hidden Secret to a Successful Heat Pump: Pipe Size Matters
@old_scientist Just to say that during our retrofit, we...
By Toodles , 1 day ago
-
RE: Daikin Altherma 3M ASHP and British Gas Hive Home
We have a Daikin EDLA08 8kW monobloc (DHW is handled se...
By Toodles , 1 day ago
-
@old_scientist @jamespa So this was last nights DHW r...
By bontwoody , 1 day ago
-
-
@springswood we install these nationwide and I have the...
By dgclimatecontrol , 1 day ago
-
RE: DESNZ doing a survey which asks the right questions!
Fair comment. I have a feeling that ratings more gen...
By JamesPa , 1 day ago
-
Thanks! My consumer unit collection is ready with the W...
By Batpred , 2 days ago
-
RE: Designing my house system with a mix of air to air and air to water
@jamespa Cheers James, it's great reading. In quite a f...
By pipebaron , 2 days ago
-
RE: PV Panels on roof in Conservation Area
If there is any way you can determine daily oil consump...
By JamesPa , 2 days ago
-
RE: Grant 13kW Aerona3 - issues getting zones to temp
attached is prelagged in case indicates anything. &nb...
By Crimson , 2 days ago



