Joining the Renewable Heating Hub forums is completely free and only takes a minute. By registering you’ll be able to ask questions, join discussions, follow topics you’re interested in, bookmark useful threads and receive notifications when someone replies. Non-registered members also do not have access to our AI features. When choosing your username, please note that it cannot be changed later, so we recommend avoiding brand or product names. Before registering, please take a moment to read the Forum Rules & Terms of Use so we can keep the community helpful, respectful and informative for everyone. Thanks for joining!
Assessing Heatmiser Neostat Accuracy: How and Why to Calibrate Them
Moving into our home brought the advantage of an already installed underfloor heating system, regulated by Heatmiser Neostats. These devices, promising precise control and energy efficiency, became a focal point of curiosity about their accuracy in temperature regulation after it was raised on a recent YouTube we posted. To assess this, I used a FLIR ONE thermal imaging camera to compare the thermostat readings against the actual environmental temperatures across different heating zones.
The process unveiled unexpected discrepancies between the Neostats' temperature readings and the thermal camera's more accurate measurements. Additionally, it highlighted hot spots within the thermostat units, potentially influencing the accuracy of the readings and, by extension, the effectiveness of our home's heating system.
Motivated by our findings, we recalibrated our Heatmiser Neostat thermostats.
How to Recalibrate Heatmiser Neostat Thermostats
🔥 Britain’s Heat Pump Shitshow
How Installing a Heating System Became a National Nervous Breakdown
Free UK shipping.
📗 Heat Pumps Explained
A Jargon-Free Guide for Homeowners
Rewritten and updated for 2027
📘 From Zero to Heat Pump Hero
🛠️ Bodge Buster
New to heat pumps?
Take the Heat Pump Fundamentals course and use INTRO50 at checkout for 50% off.
How do you know that the thermal camera or any other reference device is actually providing accurate readings?
What is the manufacturer's specified accuracy for the devices being compared?
@derek-m that thought crossed my mind while I was working on this, leading to a humorous vision where I found myself testing the device used for testing the thing that was testing the other thing. 🤣
🔥 Britain’s Heat Pump Shitshow
How Installing a Heating System Became a National Nervous Breakdown
Free UK shipping.
📗 Heat Pumps Explained
A Jargon-Free Guide for Homeowners
Rewritten and updated for 2027
📘 From Zero to Heat Pump Hero
🛠️ Bodge Buster
New to heat pumps?
Take the Heat Pump Fundamentals course and use INTRO50 at checkout for 50% off.
Posted by: @editor@derek-m that thought crossed my mind while I was working on this, leading to a humorous vision where I found myself testing the device used for testing the thing that was testing the other thing. 🤣
In the real World, the test equipment should be at least 3 times more accurate than the device being tested. So if the device being tested is specified as providing an accuracy of +/- 1C, then the test equipment should have an accuracy of +/- 0.33C or better.
This works all the way up the chain to National and International standards.
Obviously most people don't have access to intermediate standards let alone National or International ones, but there are still tests that can be performed at home.
Melting ice will be at 0C and boiling water will be at 100C, under standard atmospheric conditions of 1 atmosphere.
Heatmiser Neostats are also used by Grant. Theirs are Grant branded, but identical items. They have up to 3degC adjustable differential if I recall, so are well suited to renewable heating system control.
I had a Heatmiser Neostat installed with my Ecodan. I was told, I think, by Brendon that it was a simple on-off switch not suited to ASHP control. He advised stripping it out and installing Mitsubishi components. I did exactly that.
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.
@morgan Likewise, I had a Neo Air Thermostat installed originally, at that time, my choice of a Homely smart controller was not yet available; as soon as the Homely kit was available for my Daikin, I had the system changed over. The Neo Air, is very crude - just on/off and not really very suitable for a heat pump system at all. Regards, Toodles.
Toodles, heats his home with cold draughts and cooks food with magnets.
@toodles I wish Homely was available for my Ecodan but apparently they have no intention of providing for it.
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.
Posted by: @morganI had a Heatmiser Neostat installed with my Ecodan. I was told, I think, by Brendon that it was a simple on-off switch not suited to ASHP control. He advised stripping it out and installing Mitsubishi components. I did exactly that.
Ours will also probably go when we commence with the work of rectifying our installation. It’s going to be carnage. So much superfluous crap will be removed.
🔥 Britain’s Heat Pump Shitshow
How Installing a Heating System Became a National Nervous Breakdown
Free UK shipping.
📗 Heat Pumps Explained
A Jargon-Free Guide for Homeowners
Rewritten and updated for 2027
📘 From Zero to Heat Pump Hero
🛠️ Bodge Buster
New to heat pumps?
Take the Heat Pump Fundamentals course and use INTRO50 at checkout for 50% off.
Posted by: @editorPosted by: @morganI had a Heatmiser Neostat installed with my Ecodan. I was told, I think, by Brendon that it was a simple on-off switch not suited to ASHP control. He advised stripping it out and installing Mitsubishi components. I did exactly that.
Ours will also probably go when we commence with the work of rectifying our installation. It’s going to be carnage. So much superfluous crap will be removed.
You must post a report/summary when it's done. I'm keen to know how it goes. Also still trying to get a Heat Geek to review my install.
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.
@morgan we intend to document everything and show the difference. Where in the UK are you based?
🔥 Britain’s Heat Pump Shitshow
How Installing a Heating System Became a National Nervous Breakdown
Free UK shipping.
📗 Heat Pumps Explained
A Jargon-Free Guide for Homeowners
Rewritten and updated for 2027
📘 From Zero to Heat Pump Hero
🛠️ Bodge Buster
New to heat pumps?
Take the Heat Pump Fundamentals course and use INTRO50 at checkout for 50% off.
- 27 Forums
- 2,800 Topics
- 66.2 K Posts
- 2,923 Online
- 7,206 Members
Join Us!
Installer Finder
Degrees of Separation
Latest Posts
-
At this point, whenever someone mentions our heat pump,...
By Mars , 7 minutes ago
-
RE: Say hello and introduce yourself
@e-a-west as the good Major said, welcome to the forums...
By Mars , 28 minutes ago
-
RE: New Build 3 Phase or 1Phase
We are on three phase power because it's an enormous li...
By EtchedPixels , 42 minutes ago
-
RE: How much of your renewable and home setup would still work if the internet went down?
Yes I actually have a copy of a tool that whenever a ce...
By EtchedPixels , 10 hours ago
-
RE: How will removing the standing charge on gas bills benefit heat pumps?
The shoulder months are very difficult to judge COP on ...
By scrchngwsl , 11 hours ago
-
RE: Indevolt Batteries UK Support & Info Thread
@editor Hi, To resolve this, please tap on the A...
By Indevolt Tech , 17 hours ago
-
RE: Double or Triple Glazed Windows?
Posted by: @singlespeed With 9 years repairing windo...
By Rob of York , 1 day ago
-
@transparent we’re still running a secure version of PH...
By Mars , 2 days ago
-
RE: How quickly would you want/expect heat recovery to take from setback?
Much longer than that here. The heating isn't even on. ...
By bobflux , 2 days ago
-
RE: Passiv Smart Thermostat - Help & Forum Support
Obviously the weather is changeable but there's a defin...
By Singlespeed , 2 days ago
-
RE: The Changing Jet Stream Could Challenge UK Air Source Heat Pumps
@rob-of-york I must admit that when we had a Daikin hea...
By Toodles , 2 days ago
-
RE: Forum updates, announcements & issues
Get the Renewable Heating Hub heads-up on WhatsApp. I...
By Mars , 2 days ago
-
RE: Safety study for plug in batteries out to tender - looks like Q3 2027 at best before legal
@editor I pointed out to the one of the Fuse execs that...
By dansus , 2 days ago
-
RE: 15kw pump for 225m2 1990's house - over kill?
@seaviews As well as loft insulation, there are othe...
By Rob of York , 2 days ago





