C17MR02N0B with 900w headline
Do you have a Neff / Siemens / Bosch built in microwave oven or combination oven and think it’s energy efficient? You may be surprised by what we’ve found – it’s not good news, here’s why.
There are two issues. Firstly on the ‘normal’ 600 watt setting the microwave oven consumes over 3kW similar to an electric kettle. Secondly, on the highest microwave setting ‘Max’ or 900 watts, if your model has the audacity to display it, the pathetic inverter only pushes out the 900 watts for a couple of minutes then reduces to below the 600 watt setting without telling you. Here’s what we discovered.
Excessive power consumption
Energy saving is on most consumer’s minds given the huge increase in the cost of electricity and gas prices in 2022. Here in the UK our energy provider E-ON has doubled our monthly bill So, like many, we decided to do a power audit here at Retro Radio to identify waste and reduce our consumption. I reported some previous findings in an earlier post Household standby power consumption and updates to highlight the savings we’ve made.
During the audit we discovered a wolf in sheep’s clothing – the Neff combination microwave oven type C17MR02N0B. I guess many consumers have been lead to believe using the microwave to heat food is more economical than conventional electric ovens. So it was with some surprise when I discovered our Neff N70 / C17MR02N0B was consuming over 3kW on the 600watt setting!
Power rating for microwave ovens has always been confusing given that wattage refers to the microwave power that’s generated to heat the food or drink rather than the input power it consumes. Microwaves are typically only 50% efficient so your 800w setting will actually consumer around 1600w, double the power. You may find both input and output power levels displayed on the back of older standalone microwaves.
But our built-in Neff combi oven was demanding over 5 times as much input as it was producing output – so can this be right, is it faulty? The answer surprisingly is no, it’s been designed this way yet is boasts a good energy rating. Here’s what we discovered.
The oven was installed in December 2019 so was out of warranty as the nice BSH customer service representative told me (Bosch, Siemens, Gaggenau and Neff brands are all owned by BSH Hausgeräte). I’d waited patiently being told to hold the line in three languages as she consulted her technical department to answer my question.
Well since we had purchased a combination oven that had both microwave and conventional heating my measurement of 3.45kw was within the rating for that appliance. Hmm, I began to smell an undercooked rat. I asked if such a poor efficiency was normal for a Neff appliance – a brand that promotes itself as producing quality built-in kitchen appliances. The issue would need an engineer to visit I was told.
As a gesture of good will on this occurrence BSH were willing to send out an engineer to inspect the oven to see if it was faulty. If a fault is found we would have to pay as it was out of warranty. The Consumer Rights Act 2015 here in the UK is supposed to provide some redress for up to 6 years. But that is more an act of comedy as the right is between consumer and retailer not the manufacturer. So if the oven was part of a house renovation and supplied by third party there are often too many contract hoops to jump through. And the onus is on the consumer to prove the product is defective due to manufacturing or design defect which for many requires professional inspection that’s costly.
How long do Neff expect their ovens to last I asked? Well it depends on how much the appliance is used and treated she replied. The ‘usual get out of jail free’ answer manufactures love to use. Manufacturers could fit a simple usage meter that tracks how often the appliance is used to quantify but as it’s not in their interest few do.
Shortly after the combi microwave, along with its sister folding door conventional oven, was installed we’d hear a loud buzzing noise for a few seconds after being used. We’d tried to record the noise that occurs intermittently and for a short duration but by the time we’d fumble to switch on the phone’s video the sound had stopped. We’d mentioned it to the nice Neff service engineer who’d been called out to replace the conventional oven’s display that had decided to get dimmer day by day. Fortunately the Neff oven was still under warranty so after a month with two visits, to identify the fault and return with parts two weeks later the display was working again. The engineer could not hear anything wrong with the microwave so it could not be fixed. We asked if it could be logged so if it did fail like the screen it could be covered under warranty.
Well Neff warranties don’t work that way. They won’t investigate intermittent faults and they would not log the noise as a fault as we could not be sure which appliance the noise was from! But I could demonstrate the excessive power consumption to the engineer.
If you have a smart meter it may be worth checking your built-in microwave oven to see just how much power it’s consuming. If like us you find it’s taking over 3kW on a 600 or Max setting then complain.
It’s pretty simple to check. Click the buttons on the on smart screen display to show the electricity consumption and note the number of watts. Then fill a microwaveable dish or glass jug with half a litre of cold water. Switch on the microwave for 2 minutes and monitor the smart meter display. Make a note of the highest reading and note any changes. When the microwave completes after 2 minutes write down the reading. Subtract the average of the two readings with the microwave off from the highest reading with the microwave on. In our case the two off readings were 235W and 248W average 241W and max reading was 3.19kW so consumption was 3190-241 = 2949 or approx 3kW.
As a comparison we tried our 20 year old standalone 800w microwave with its rotating glass shelf. It draws just 1320w so is around 60% efficient compared with the Neff combi that can manage a mere 20%.
After more in-depth investigation (reading the manual) it turns out the increased power consumption on microwave is due to the appliance design firmware that switches on the heating element at the start of a microwave only programme to reduce condensation. Subsequent runs of the microwave don’t need the heat as the element is still warm. The oven door is also likely to be covered in condensation anyway so it needs a drying programme to run afterwards. You can appreciate all this consumes more power but there is an option to switch it off if you read the manual.
900 watts is not for cooking
You may have wondered why your expensive Neff 900w flat bed microwave is taking longer to heat than the cheap old freestanding microwave you’ve always used. Ding. Well I can tell you why and you may be rather angry to learn that the 900w setting – yes the one that says an emphatic ‘MAX’ on the display and takes several button presses to select rather than the default 600w – is not designed to cook food. Yes that’s right you can’t actually use the 900w headline setting to reheat your ready meal or quickly defrost that soup portion you made in a batch to save time.
How can this be true? Well it says so in the manual on page 17. You did read the instruction manual before you decided to purchase didn’t you? No, we didn’t either. We saw the 900w headline on the product tag in the show room and on the website description. And we checked the specification that says 900w as the maximum microwave output. So we assumed we could use it on 900w just like we have always used our 800w standalone for.
No, not according to Neff. They decided to prevent their ‘innovative intelligent inverter technology’ from over heating they would design it to reduce its power level to 600w or below after a couple of minutes on Max. But the clever little appliance fails to display its reduced output – it shows Max – so they could not allow it to be used to cook or heat food as that may be deemed liable. So they simply hide the limitation on page 17 inside the instructions where they are pretty sure few will bother to read and it’s the customer’s fault if they fail to read it.
So what can you use the 900w for I hear you ask? It’s been designed to heat liquids. Make of it what you will. Water maybe? Well if you decide to heat water in your £1000 microwave I’d ask yourself do you have a £20 kettle, as the kettle will heat water in a fraction of the time it takes the ‘innovative intelligent inverter technology’ to. And for far less money.
Inverter microwaves
Don’t be fooled by the innovative inverter technology. Your humble mobile phone charger probably uses the same technology to transform the 240v AC mains power into the 5v DC needed to charge your mobile. An inverter does a similar job to the larger heavy transformer that was used in older microwave ovens and the black wall wart chargers of yesteryear.
Inverters can be more efficient at regulating the power providing a smoother delivery. But they are not designed to overheat at normal output power levels.
We can’t let manufactures get away with this kind of thing any longer. It needs you and I, the consumer, to complain to BSH and share this issue on social media. I was shocked at the VW emissions scandal that rocked the car market several years ago. How could such a respected brand act this way. Respected manufacturers disgraced.
Will I be buying another Neff / Siemens / Bosch kitchen appliance? No and I recommend you don’t waste your money either. Not only will you have the cost to replace the oven in a couple of years when it’s out of warranty, or pay for expensive spare parts and engineer’s visit if you go for a repair — you will also have paid for 80% more energy to use the microwave when you’d thought you were saving money.
Power Reading Notes
Microwave ovens can emit small amounts of radio frequencies that interfere with smart meter displays that use similar frequency to communicate with the smart meter. If you operate the display close to the oven like I’ve shown in the photo it could show an incorrect reading or stop receiving signals from the smart meter. Always keep the display away from the oven when you start it and wait until you see a stable reading before noting the consumption. Remember the display may stop updating when the microwave is on giving you a false reading. Check by switching on an off another appliance when the microwave is running to ensure the display’s signal is not being blocked.
10/04/2023 at 1:52 pm
In December 2020 i bought a Neff C17UR02N0B Built-In Microwave, costing £600, now over£700, at the beginning of April 2023 it stopped heating anything and slso emitted a burning smell. John Lewis says “warranty ran out less than 4 months ago, we can’t do anything. Am I entitled to have it repaired or replaced? 2 years 3 months and 3 weeks isn’t old in my view and I believe it may be a manufacturer fault.
11/04/2023 at 6:47 am
Sorry to hear about your Neff built-in microwave, another casualty. Consumers have up to six years in the UK, or 5 years in Scotland, to complain under the limitation act – part of the Consumer Rights Act 2015. But after 6 months, the consumer has to prove the item had a manufacturing or design defect. The manufactures and retailers know this and play off against each other bouncing the consumer into submission. But it’s worth trying and be persistent. Search the web for others that have the same issue and use social media to raise awareness. Call Neff and see if they will provide a free of charge call out to investigate what the problem is. Ask if there’s been a recall or technical bulletin about the issue. They may offer a free of charge repair if they know you know there’s an issue. Good luck.
11/04/2023 at 7:49 pm
Looking at the spec of your C17UR02N0B it shows the 900w microwave power level is not designed for heating foods as was our combi C17MR02N0B. John Lewis still advertise the 900w setting without stating it can’t actually be used for food. If you’ve been using your microwave on the 900w setting it could have overheated and lead to early failure of the inverter or magnetron. So you could try challenging John Lewis on the product marketing as we did since your contract is with the retailer. You would need proof of what’s failed and likely cause which Neff service engineers could provide.
If you’ve just used your C17UR02N0B on the 600w setting then early failure indicates bad design or faulty manufacturing. Our 20 year old standalone microwave is still working and cost less than £100. As I say in the post the more consumers that complain about Neff’s products and avoid buying them in the first place will force the BSH to improve.
11/04/2023 at 7:57 pm
Take a look at the customers product reviews to see others have found the same problem:
Neff C17UR02N0B – 15 customers give just 1 star
John Lewis C17UR02N0B – 14 give just 1 star
Ignore Incentivized reviews!
05/08/2023 at 3:23 am
Confused about my new NEFF combination oven. Why put a 900w setting if it’s not to be used for cooking food?
05/08/2023 at 6:03 am
Hi Sylvia – yes, it’s not just confusing it’s wrong and NEFF’s retailers should not be allowed to market the appliance with the 900w headline. I’ve complained and you should too. Our retailer RDO did offer a refund option or discount on an alternative appliance but neither were suitable as we discovered this 2 years after purchase. There’s a Panasonic combi oven that does provide a true 1000w power setting for cooking but it won’t match the slide oven if that’s what you want.
The more customers that complain to retailers the more chance they will force NEFF and owner Bosch Siemens Hausgeräte to change. Good luck and if you keep it don’t be tempted to use it to cook food as it won’t provide the expected temperature and could be dangerous. Judging from reviews the appliance’s microwave also is prone to fail when used on 900w setting which is why it defaults to 600w. Shame on BSH for deceiving customers in this way.
15/02/2024 at 9:05 am
Shocked to read this post, but it explains why when using my combi oven and microwave model no. C17MR02NOB/38 on microwave only, the grill element comes on. Although I have had the oven for over 6 years I have only just noticed this happening. I called Neff customer support and they said they had not heard about this issue before.
Fortunately I still have my ancient Panasonic stand alone microwave which I will use more for microwaving.
18/02/2024 at 10:32 am
Yes Kath it is shocking. We too have stopped using the Neff combi and use our ’90s Daewoo microwave which is noisy and takes up worktop space but is so much more efficient. To think we paid over £800 for a Neff product we only rarely use as a plate warmer is also frustrating. Given the switch to an air fryer, we just use the main Neff oven for baking bread and pizza. Neff / BSH must improve the efficiency of their appliances or their market share will fall off a cliff. I don’t believe Neff customer services when there are so many reviews that contradict what they tell you.