The OVO SMETS2 Smart Meter Health Check (SMHC)

  • 10 September 2020
  • 56 replies
The OVO SMETS2 Smart Meter Health Check (SMHC)
Userlevel 7

Updated on 14/02/22 by Jess_OVO


Your guide to the SMETS2 Smart Meter Health Check (MHC)



If you think there might be communication issues with your SMETS2 meters, we’d recommend checking out the advice given in the following topics first:  


Still having communication difficulties? A Smart Meter Health Check (SMHC) can help diagnose things. Carry out the checks below - Any unexpected results should be forwarded to our Support Team for further investigation. 


If your Secure Liberty SMETS1 smart meter is having communication issues, find the SMETS1 Smart Meter Health Check here


The SMETS2 smart meter health check


There’s currently two manufacturers of SMETS2 meters that OVO installs: Aclara (Flonidan for gas) and Honeywell. They’re similar in shape and style but the placement of the buttons, Meter Serial Number (MSN) and WAN lights may differ. Aclara have two versions of their electricity meter V1 and V2.5. We’ll be moving onto installing only V2.5, but V1 has already been installed in some homes. There are only small differences between the two versions (images found near the bottom of this guide) and there are other versions of SMETS2 meters that are being installed by other suppliers.


Are the Meter Serial Numbers (MSNs) correct?


We first need to make sure that the meter(s) we’re dealing with are correct (mistakes can sometimes be made, meaning the wrong MSN is listed on an account). 

Where can I find the serial number on a smart meter?


The MSN for an S2 electricity smart meter can be found near the meters barcode above the display. The Aclara version of the SMETS2 will start with either 17M, 18M, 19M, 20M, 21M or 22M (depending on the year the meter was manufactured). The Honeywell meters will start with either 17K, 18k, 19K, 20K, 21K or 22K.


The MSN for a gas smart meter can be found below the display. It will start with G4F. For Honeywell, it will start with G4K.

You can check these match the meter details shown on the ‘Meter Readings’ page on your online account or OVO app (download for Android or iOS).


Are the meters commissioned?


If the HAN light isn’t flashing on the smart meter communications hub (attached to the top of the electricity meter), this suggests that the meter hasn’t been commissioned. Further to this, on the screen itself, a commissioned meter would have a signal bar and "HAN" written on it to indicate connection.

Our Support team can also do some checks for this. 


Is there a WAN connection?


These are the lights on the communications (comms) hub for SMETS2 found on the electricity meter:


Lights on the communications hub

SW - Represents the status of the comms hub's software
WAN - The comms hubs ability to communicate with us
MESH - Communication through another S2 comms hub (will be more applicable when there are more S2 smart meters)
HAN - Communication of elec meter, gas meter, and IHD with the comms hub
GAS - Gas meter HAN connectivity


What lights are flashing and how often? - Please note that this is very different to SMETS1


Low - every 5 seconds - everything is fine here
Medium - every 3 seconds - searching for connectivity  
High - every 1 second -  connectivity issue
Off - connectivity issue

Please check your electricity meter and confirm what the LED light labelled 'WAN' is doing. The lights are on the communication hub (shown in the picture below), which is above the electricity meter.

If the lights aren’t flashing every five seconds, this indicates an issue for our Support team need to investigate further. 

When fitting SMETS2 meters in low WAN areas engineers will fit an aerial to the meter. On these meters there’ll be a box (yellow arrow in pic below) sticking out of the comms hub and a wire connecting to the a small (T1) or large (T2) external aerial. So if there are WAN issues and an aerial has been fitted, make sure you find out which size has been installed. Please bear in mind that if you have a larger aerial already installed, there is nothing more we can do to improve WAN.


Exact appearance may vary



T1 aerial (6") and T2 aerial (12”)


T2 aerial (12")


Is there a HAN connection?


The best way to check HAN is on each of the components that connect to the HAN. 


If any of these symbols are missing then it indicates they’re not connected to the HAN. 

In addition, on the comms hub, the HAN or GAS light may be flashing every second or not at all if there’s an issue with the HAN. A medium flashing HAN light on the comms hub (5 flashes, pause and repeat) indicates a HAN set up and connected with devices. 


Is the meter clocking usage?


Aclara (Flonidan for gas)

  • Electricity: There’s 2 buttons on an electricity meter. Pressing B will cycle through all the menus on the meter screen and pressing A will cycle through all the sub menus. To take an electricity reading, you will need to press A - TOU rate 1 will be the electricity reading. For Economy 7 members, TOU rate 2 will show the rate 2 reading.
  • Gas: Gas meters have A, B and C. Pressing C will give you the menu and A & B will allow you to scroll through the options. The balance section is where you can check the reading (when you wake up the meter it should automatically default to the reading screen). Screen 1 - readings, active tariff price, standing charge, export reads, meter mode.


  • Electricity: Press the top button once or twice to access the reading. 
  • Gas: Press the middle button once or twice to access the reading. 

Aclara V1 Elec

Aclara V1 Elec

Aclara V2.5 Elec


Aclara V2.5 Elec

Flonidan Gas

Flonidan Gas


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56 replies

Userlevel 7
Badge +3

A few points to add to what @Tim_OVO ’s writing here:

Honeywell is now a division of Elster. Most other websites seem to call these “Elster meters” even if they actually say Honeywell on the front. The two names are interchangeable.

SMETS2 Gas Meters: AFAIK most of the SMETS2 sites installed by OVO to date have Uniflo gas meters made by the Dutch company, Flonidan. Could you please clarify this, Tim? You’re suggesting that OVO is only supplying Honeywell gas meters.

MESH network communications. There’s actually a sizeable installed base of Communications Hubs with Mesh networks. I have one because I live in a rural area! The Mesh indicator flashes to indicate that the network is alive. It doesn’t tell you anything about whether data is being transferred across it.


Userlevel 7

Honeywell is now a division of Elster. Most other websites seem to call these “Elster meters” even if they actually say Honeywell on the front. The two names are interchangeable.

SMETS2 Gas Meters: AFAIK most of the SMETS2 sites installed by OVO to date have Uniflo gas meters made by the Dutch company, Flonidan. Could you please clarify this, Tim? You’re suggesting that OVO is only supplying Honeywell gas meters.


Thanks @Transparent - this is correct. I’ll be posting a tutorial as part of this DIY series on Monday, all about S2 smart meters. We’ll go into a bit more detail about Honeywell/Elster, and about Aclara (elec) and Flonidan (gas) meters then. 


For now, I’ve updated this topic to include Flonidan rather then Aclara for those gas meters. :) 


Also, tomorrow I’m posting 2 tutorial topics on In Home Displays. One giant guide about the multiple IHD versions for S2 (and the different ways to diagnose and fix connectivity issues). One about the S1 Pipet IHD. I have updated our existing S1 Chameleon IHD guide here today!


This should really help us get to grips with these different versions, issue indicators, fixes. @Transparent I think you’ll like the S2 IHD guide….. :blush:

Userlevel 7

Oh and I’ve fixed this topic so the images work now! 

my meter is different than both these images it is aclara sgm1411-9 Standard 420 ,and only has WAN and HAN lights , lights flash every 5 seconds but you dont seem to receive data.

Userlevel 7

my meter is different than both these images it is aclara sgm1411-9 Standard 420 ,and only has WAN and HAN lights , lights flash every 5 seconds but you dont seem to receive data.


Thanks @stalybooks - I think this is a SMETS1 Aclara smart meter, which will be upgraded to the DCC and able to communicate with all suppliers at some point. 


As our SMETS1 smart meters are ‘Secure Liberty’ models, I know the DCC upgrade schedule for these meters is September 2020 - September 2021. 


Where’s a good resource for customers to find upgrade plans for other SMETS1 meter types, does anyone know, @Transparent ?

This was fitted by OVO about 2 months ago.

Userlevel 7
Badge +3

The best website for background information on Smart Meters is SmartMe, and there’s a timetable for upgrades of SMETS1 meters towards the bottom of that technical page. I’ll reproduce it here with a minor amendment based on what an OVO Engineer told @Tim_OVO and I.


OVO have a 12-month window during which they expect to migrate all meters to the National Smart Meter Network.

Some have already been moved across, particularly those at sites on the Priority Services Register. For obvious reasons it would not have been acceptable for these to have been receiving software changes in the middle of winter in case something went wrong.

Userlevel 7

This was fitted by OVO about 2 months ago.


I’m now a tad confused. @stalybooks can you send us a screenshot of the electricity smart meter and I can confirm make and model with some experts, unless I’m beaten to it by our very own community experts…


Thanks for the above, @Transparent - super handy!


Userlevel 7

Thank you, @stalybooks - this is so handy as I’ve been able to confirm from a smart meter engineer that:


“This is a new Aclara meter but the comms hub is a Northern region comms hub. All EDMI hubs are Northern region, Toshiba and WNC hubs are South and Central”


You’re able to use those WAN and HAN indicator lights as advised the guide to determine communication  :blush:

Userlevel 2

Very informative tutorial - thank you.

My SMETS2 meters were installed by my previous supplier (Bulb) and have never really worked properly. They have worked intermittently, with my IHD showing real-time usage (as noted whenever I switched on the kettle for a cup of tea - scary!) but after a few days it would revert to a waiting for data message. More recently, it has gone to showing random usage numbers which don’t change no matter how many appliances I switch on or off and - interestingly - all the other IHD on-screen text is now in Welsh! (I don’t live in Wales btw).

I wasn’t aware until reading this article of what the flashing sequence of the WAN/HAN lights should be. Mine flash every 5 seconds or so and my IHD appears to be receiving a good wi-fi connection, so all would appear to be fine according to what you say above. For your information, my comms hub is an EDMI Standard 420, and my meters are Landis & Gyr (E470 Type 5394 for electricity, and G470 672 for gas).

My monthly usage is now usually  estimated by Ovo despite having so-called “smart” meters, so I have reverted to supplying monthly meter reads online, which kind of defeats the object of having them installed in the first place. Will they be forever “dumb”?


Userlevel 7
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Welcome to the forums @Grim Up t'North !

Could you fill out your profile for us please? It can help us to give you the right advice a bit faster. :sunglasses:

I think I know how to help you fix some of those issues. The guides over here 

Should help you to get your IHD switched back to English. But if you get stuck, we’ll guide you through it.

As for your meter issues, that sounds like it could be one of several things. I believe @Transparent might have some advice that can help here. But hopefully they’ll recover eventually.

Userlevel 2

Thank you @Blastoise186. My IHD is at least now in English once more (even if the numbers on it make no sense!)and I have discovered it is an IHD3 type, thanks to the tutorial you directed me to.

Userlevel 7
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Glad to hear it. :sunglasses:

Misbehaving IHDs are a common one that we’ve seen quite a few times and I know there’s a few threads on the forums somewhere but I can’t seem to find them right now. But I’ll let you know if I manage to find them.

If you need help with anything else, definitely feel free to stop by the forums again too. While volunteers such as myself can’t handle account specific queries, there’s a lot that we can do which might save you a call… Or three...

Userlevel 7

Hi @Grim Up t'North and welcome to our lil community of problem solvers large and small :blush:


For anyone else with a Welshy IHD, the bit of that tutorial @Blastoise186 linked to confirms:




IHD is showing text in Welsh

Occasionally, IHDs have been known to default to Welsh. Follow these steps to change back to English:

1. Tap the”OK” button at the bottom of the IHD screen.
2. Tap the right arrow until you see “Gosodiadau Wedi anfon yr” and tap OK.
3. Tap the right arrow 8 times until you reach the option “Dewis iaith Wedi anfon yr” (if this doesn't work, you may need to try the next option: “Clirio Gosodidau Wedi anfon yr") and tap “OK”.
4. Tap the left arrow to select English, then tap "OK".





Misbehaving IHDs are a common one that we’ve seen quite a few times and I know there’s a few threads on the forums



Yep and I've been in discussions with some different teams at OVO to try and sort this out, at least of us forum members. 


At some point next week, I'm going to be adding a template set of questions to these smart health check and IHD tutorial topics, which I will ask the likes of @Grim Up t'North to complete as a comment in the topic. That makes it super easy to copy and paste it in a web chat, along with the topic URL, which the adviser you speak to can then copy in a ‘case’ to our Smart meter and IHD fixers. If they then fix it and confirm what they did, @Grim Up t'North and others can then update the topic to confirm, allowing us to see trends. This has a few different benefits as it speeds up the convo @Grim Up t'North has to have with our web chat team, whilst making sure the fixers have everything they need, speeding up the diagnosis. 


More on this to come next week. Have a lovely weekend everyone! 


Userlevel 7
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Nice one!

I think it might also be useful to have templates on hand for as many common setups as we reasonably can, since a one-size-fits-all doesn’t always work. :wink: The main snag here being that the SMETS1 Smart Meter Health Check questions for the Secure Liberty 100 family meters don’t work very well for Aclara SGM1300 Series meters. I don’t think Aclara puts numeric keypads on any of their meters...

I think I still have a copy of the template which the support team gave me, so I’d be happy to try and adapt it to cover the Aclara ones if you’d like me to. :slight_smile:

Userlevel 2

Well, strangely enough, since I got my IHD to speak to me in English once more, the other data on it (certainly as regards electricity) seems to have miraculously come back to life! Now when I switch an appliance on or off, at least the figures on the display change as I would have expected. I guess I’ll have to wait and see how long it lasts, and whether my online account successfully reflects this at the end of the month.

Userlevel 7
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Thanks for the update @Grim Up t'North !

It’s definitely good to hear that your IHD is somewhat working again. Showing any signs of life at all is definitely better than nothing. The issue with not showing gas data is also known too. I’ll dig up all the relevant threads as soon as I can for you.

Please do keep us posted if your IHD gets any better or worse. It helps a lot.

I can also confirm that even with a dead IHD, your online account should still update as long as your meters are able to submit readings to OVO. If you’d like to get the best chances of this, I recommend setting your meters to submit readings on either a Half-Hourly or Daily basis, since this massively increases the opportunities to get a good reading in.

Changing the settings is of course completely optional though. If you’d rather stick with monthly, that’s cool too. You’re welcome to choose whichever level you’re happy with. :slight_smile:

Userlevel 2

Thanks @Blastoise186 and @Tim_OVO 

I’m really not sure how often the meters are set to submit readings. As they (and/or the IHD) have always been somewhat erratic in operation, I’ve simply left them in the default state they were left by the installing engineer. I wouldn’t know how to change them, or even that they could be changed by the user.

I only mentioned “monthly” because, in the absence of any readings from my meters, that’s how often Ovo choose to estimate them, which I then usually correct with a manual read. The graphs of my daily usage aren’t really any good because they simply divide my whole month’s usage into 30/31 equal parts, and the chances of me using EXACTLY the same amount of electricity every day are vanishingly small to non-existent!

Userlevel 7
Badge +1

No worries :)

It definitely sounds like your meters might need some extra attention. Hopefully Tim can give you a hand there.

In terms of changing the settings related to how often the meters submit readings, that’s not something you can change yourself, but it is possible to do remotely. As far as I’m aware, I think the default setting with OVO is Daily unless you specify otherwise. But if you’d like to change between Half-Hourly, Daily and Monthly, you can do that an unlimited number of times whenever you want, completely free of charge. OVO can also check the current settings for you too.

If you’d like to check the current settings and make any changes, the fastest ways would be either via the live chat or phone and the support team can do that for you. It doesn’t usually require an engineer visit. Half-Hourly is recommended if you’d like to have the usage charts be as accurate as possible.

I also have a handy tip too. If you’re finding that your meters aren’t submitting readings properly, you might be able to submit them manually to cover the gaps. I’m currently waiting for my meter to activate after switching to OVO recently (should be live on Monday!), but by putting in manual readings on a daily basis myself, I’ve been getting pretty good graphs so far. The more often you submit, the more accurate the bills are. :)

While I do mine daily, you can also do weekly if you’d rather not do 365 manual readings a year!

Userlevel 2

Well, it seems I spoke to soon! Today my IHD has gone back to “Elec data unavailable” although, as I speak, at least it’s still in English!

Userlevel 7
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Thanks for letting us know @Grim Up t'North . Please keep an eye on things for us.

I know this might be a bit painful, but can I please ask that you don’t have support team attempt any fixes/repairs just yet. There’s probably valuable diagnostic data on your meter and IHD that could provide helpful clues, but the short term fixes that the support team can perform will often wipe out this diagnostic data.

Tim will hopefully be back in the morning to dig into this further. Pulling the diagnostics from your meter and IHD by itself shouldn’t cause any data loss, so we’d definitely appreciate your help here too. :)

Userlevel 7

Thanks for these updates, @Grim Up t'North 


As @Blastoise186 mentioned the default communication setting is half hourly, but your online account charts indicate that we might not be getting this. Your first message indicated your meters ‘weren’t really working properly’. I think we need to dig deeper into this before reaching out to our Support team to check.


Can you let us know the results of the actions outlined in this guide topic? I’m mainly interested in the WAN light on the comms hub, and hearing from you about the mobile phone signal and the situation in the house: thick walls around the meter area, meter location info etc etc. 

Userlevel 2

Hi @Tim_OVO 

Please see attached some photos showing my meter installation and current IHD read out. Hopefully, they will be of help.

My meters are installed in my garage which is attached to the house so only separated from the hallway by one wall, albeit an exterior one. Distance from the wall on which the electricity meter is located to my IHD unit is around 5 metres.

As outlined in my original post, the WAN and HAN lights both flash simultaneously at an interval of approx 5 seconds. A red light on the electricity meter beneath the green button marked “A” flashes approx every 3 seconds. 

Hadn’t particularly noticed the signal indicator on the electricity meter before but seems OK to me at 3 bars, or should this ideally be higher? There is no similar indicator on my gas meter which is situated on the opposite wall of the garage, so approx a further 2.5 metres away. (It’s only a small garage!)



Userlevel 2