Navien UK Reviews 500

A 90-year old with no heating - phoned Navien for help and was put through to Aubrey. What a splendid chap! He courteously, patiently and efficiently guided me to a resolution of the problem. I could not have been more satisfied with the service he provided.

From my initial phone call to Navien about my boiler fault, the repair was carried out within 24 hours and the engineer was very efficient and courteous. Everything was tested thoroughly before he finished and left clean and tidy.

Our boiler has been a bit tricky however Navien sent an engineer up the next day with all the parts to get it working again :-)

Very well presented, very friendly making me feel at ease and did a wonder job getting my boiler working again. Didn’t take him long to work out what the problem was and he got straight to work and I have heat again. No mess was made. Highly recommend

My boiler has a 10 year
Guarantee. I called my local Heating company when it failed during the recent cold weather. Their engineer got it working but suggested that I speak to Navien as they thought there was an underlying fault. Rang Navien at 1pm. By 7pm thelr engineer Grant had visited found and fixed the fault. Navien is a Total Quality company in my opinion.

Navien are inefficient, and don’t care about their customers. They are leaving me without hot water and heating for 10 days. They cut you off when you speak to them, wouldn’t have another Navien boiler under any circumstances

An update- after 4 days a Navien Engineer came and fixed the boiler. Many thanks Navien. Now a week later, fingers crossed, it’s still producing hot water and heating. Thanks again.

Had a Navien boiler for about 3 yrs, warranty is for 10 yrs, experienced loss of pressure over and over again just randomly, tried on multiple times to log a support request with Navien via the web site, nothing heard back, really poor I thought.
Booked a British Gas engineer to come out, they sorted it the next day, had to change a pressure relief valve and complained that Navien were bad for spare parts, lesson learned, cost me a couple of hundred quid to fix but I was desperate...no more Navien for me after this, take note if you are reading this, after sales is important and Navien are particularly bad at it

Have gone from 1 star to 5.
Faulty boiler but at the end of the day, customer services did what they committed to, found an engineer who came out and fixed it n day.

Thank you

We got our boiler fitted by Boxt.Navien boiler.Pressure dropping after a year.We had it serviced.Phoned for engineers to come out which was about half an hour.The date n 8-1 time slot with an hour's notice phone call.No phone call! Just a message saying he was here at 12.20 looked at cameras it was 11.30.Had to phone again n they said will sort same day but 1-6 after changing my day around.Assured me i would get a phone call.If they phone n I get my boiler sorted by this company Navien I will be back on Trust pilot with a gleaming report n a 5 * but something tells me....I won't hold my breath!! The engineers came out still no phone call from Navien.The British Gas engineers-really good n hopefully sorted it now.Navien boiler is good.Boxt who fitted it are good.British Gas are excellent.So the most simplest but worst is Navien customer service!! Sort this out-its ridiculous.How difficult is it to phone a person to give 1 hours notice?! Obviously difficult....its not rocket science.Navien please sort this out!! The day after had to do pressure x 3 times phoned Navien n waiting for a phone call.Hppefully won't have to have British Gas out every week.Also contacted Boxt no reply yet

Navien UK Team always going above and beyond the call of duty - you are not only buying a great product but also peace of mind for many years to come. One of the best Customer Service Teams I have ever dealt with - well done and keep it up. Chris / Ayrshire

The Boiler broke down yet again. After phoning the helpline and being transferred to the Philippines. I was put on hold for only 43 minutes to be told someone will call me back. Luckily this time they did and was given an appointment for Thursday and told the engineer will call me one hour before arrival. This must have been lost in translation and the British Gas engineer called to say he was ten minutes away, not great as I was twenty minutes away. One very unhappy engineer who said he would come back later, 3 hours later only to tell me he didn’t know anything about the Navian boiler( great convenience boost for me) turns out he didn’t know about it as he came back Friday to try again. I called the customer service line and was told to call back Saturday morning. Called Saturday morning to be informed that a Navian engineer would visit and I would get a call within the hour. Fare enough he didn’t say what day that would be. Monday got the call to say the engineer would be there on Friday. Yes that is two weeks without heating and hot water. Good news is the coldest February. Great service NOT. A compete shambles

I originally experienced a very frustrating issue with my Navien oil combi boiler, which is only four years old and covered by a 10-year warranty. After reporting a fault on 29/12/2025, we unfortunately experienced periods without heating and hot water, which was particularly difficult with an infant in the household. There were delays with parts and communication, which caused understandable concern at the time.

However, I am pleased to say that the situation was resolved in a way that truly deserves recognition.

On 06/02/2026, Chris Peden, the National Service Manager for Navien UK and Ireland, personally attended our property to resolve the issue. Chris travelled over 12 hours round trip to ensure the fault was fully diagnosed and repaired, which demonstrates an exceptional level of commitment to customer service.

Chris was extremely knowledgeable, professional, polite, and thorough throughout the visit. He took the time to explain the issue, ensured the system was fully operational before leaving, and even provided his direct contact details for any future concerns. His dedication and willingness to go above and beyond completely restored our confidence in Navien as a company.

While it is unfortunate that it required escalation to reach this point, the level of care and ownership shown by Chris reflects very positively on Navien’s commitment to standing behind their products and supporting their customers.

Thank you again to Chris and Navien for resolving the issue and ensuring our home is warm and fully functioning again.

— A very appreciative customer

Had a visit from an engineer today who supposedly made a temporary repair, of which the boiler is still not working.
Thus saying a service is needed to get the boiler working
My own engineer cannot visit until 21st as very busy, which is understandable being the winter.
Now we will be without hot water and heating for 18 days
Call navien warranty useful... I think not!
Very unacceptable

I am writing to formally recognize the outstanding support I received from Matthew Cundill regarding the heating system at our property located in Snowdonia National Park.

Because our property is a five-hour drive from our primary residence in London, remote reliability is absolutely critical for us.

We recently experienced a total loss of communication with the boiler management system. Upon arrival, we discovered the batteries in the Smart Plus NCR10-RW Wireless Room Thermostat had been exhausted, and the radiators were failing to reach the necessary temperatures for the local climate.

Matthew provided expert guidance that went above and beyond a standard service call. Specifically:
• Permanent Power Solution: Matthew helped me find a battery replacement/power adapter solution that connects directly to the wall plug. This ensures we will never again lose communication due to battery failure of the Smart Plus NCR10-RW Wireless Room Thermostat —a vital fix for a remote property.
• Climate Optimization: He guided me through recalibrating the Weather Compensation Factor Curve specifically for our geolocation. This ensures the boiler now responds correctly to the extreme cold of North Wales.

In an era where remote management is essential, Matthew’s technical knowledge saved us from a potential disaster, including the risk of frozen or burst pipes. He is a credit to the Navien team, and his expertise has given us immense peace of mind.

I called the company as my boiler wasn't working it had an error report. My local heating engineer, who is excellent said
the problem needed done under the warranty. The boiler is 6 years old with a 10 year warranty. No one could come for a week. This was in December and snowing. I live in the country in Aberdeenshire and on my own.Nearest service engineer is Glasgow.
When he came he constantly complained about the state of the boiler. He arrived at 1.30pm and needed to be home at 6.30. It's a 3 hour drive. Not my fault. I had it serviced a month prior to the visit. He headed off said it was fixed. It wasn't, I phoned him and he came back. Not happy. 45 minutes later he left. Still not working. He showed me to press a switch inside the boiler, it's an outdoor boiler. It stayed on 5 minutes and went off again. I phoned and he told me to get my engineer to sort it. At my expense of course. Warranty not worth the paper it's written on.
I contacted my engineer and asked him to quote me for a new boiler. A reliable one with local workforce. 3 days later he fitted it. A Grant combi boiler. Fabulous. My house has never been so warm. Navien is total rubbish with very poor non existent back up. Avoid at all costs.

I emailed Navien after they commented on my review saying I would like to discuss further. To date, 8.2.2026 I have not had a reply to my email. Sounds about right!!!On 16th February still no contact from Navien!! True to form sadly. Avoid this company!!

The boiler was repaired under warranty which was great. The engineer was very knowledgeable and the job was completed quickly. The only slight niggle was that it took a week to get him there and while we had not moved in and wasn’t a major problem if we were living there it would’ve been a major headache.

I needed to report a hot water issue and got a call back within minutes of contacting the installation company. Aubrey at Navien was wonderful; extremely helpful and so pleasant to talk to. Thank you !!

Bought a Navion Boiler last year as was promised they were a good quality boiler .......I was pleased with it u till 2 days ago when it lost pressure and would not fire for either hot water or the heating. Was passed on to Navion custo er service as it has a 10 year warranty.......however it will take a week for an engineer to come out. No hot water or heating for this time in mid winter with the cost of 5 snd a half grand to have it installed.....and the customer service attitude seems to be I should be grateful they are coming out at all as 'they are not a service company'......makes you wonder how valuable that 10 yr warranty really is?! Wish I'd stuck with my gut and bought a Worcester Bosch!

Wow!

Where to start… I suppose context first!

We had a Navien boiler fitted via Boxt in Feb 2025.

It broke January 2026.

We have been without reliable heating or hot water for a week now, this includes 1 telephone visit and 1 engineer visit.

Currently heating starts, makes a rather disturbing noise, error messages and lights, before shutting off, cooling down and starting again on a 4 hour cycle….

Boxt were appalling ( with the exception of a couple of engineers) their customer service really ended with, “Just call Navien yourself “

So I Did

My God, it’s the most frustrating conversations I’ve ever had. I think I spoke to 3 different individuals throughout the week. So let’s go through them individually…….

Customer service rep 1.
Just plain rude, absolutely rude! However engineer booked in relatively acceptable time for a Saturday. I’m not unreasonable and appreciate weekend work

Engineer 1
Talks us through fixing it over the phone, twisting various knobs…. Unsurprisingly it broke again almost immediately

Engineer 2.
Lovely chap. Replaced a part on the boiler, but it broke again very quickly only this time it lost power too. He also reported the thermostat to Boxt

Boxt engineer brought a new thermostat and tightened some screws on the boiler and power was returned… it still doesn’t work, but at least there are some pretty lights to look at.

Customer service rep 2
Insinuating from the information from engineer 1 the broken boiler was our fault, and we should be grateful for all help.

Customer service rep 3
Attempted escalation to get a third visit to fit in with our schedule rather than theirs…. I very much doubt this happened.

The third visit will occur 3 days after the call was raised, require me to take a 3rd afternoon off work. A total of 7 days without reliable hot water or heating

I have probably spent as long chasing issues with both Boxt and Navien as I have in my full time job ( ok that’s an exaggeration but I’m pretty cross still so forgive me).

I thought Boxt were one of the worst customer experiences I’d ever had, then I spoke to Navien.

My only advice is don’t even consider a Navien heating system. Especially if you are Elderly or vulnerable, or acting on behalf of elderly relatives. Please don’t risk it, I’m middle aged relatively well and active. But I’m cold and unable to bathe or wash up without boiling a kettle or wash and dry my uniforms for work. I still think over a week for a boiler repair is unacceptable, particularly in January. But I’m particularly worried for those prone to hypothermia, or to vulnerable to survive without these common amenities. These people exist, I work with them.

As a result of the poor care, and absence of conscience, professionalism, or duty of care displayed by Navien I hope Boxt stop using them.

I work in a public service role, by taking repeated afternoons away from work, to allow for Naviens incompetence has affected many people, not related to my boiler. It must be understood that as customers we still have lives to lead, commitments to fulfill and jobs or roles in society. It shouldn’t be expected that customers drop everything repeatedly to allow engineers to fix problems that shouldn’t exist to begin with. As customers these issues should be fixed at our discretion not the company at faults.

This is Navien/Boxts problem, caused by either poor installation or poor products compounded by poor customer management. The effects are felt by not only myself, but my family and the public I represent in my professional role. Simply unacceptable.

I’m sure the response will be something to do with the number of engineers available, short notice etc. I do not accept this. There are many local engineers, we know subcontractors are used.

In summary don’t, please just don’t I suspect although can’t prove I’ve been misled, compounding generic poor if not unethical service and rude public facing service staff…..

Not really the magic formula is it

I chose Navien believing the warranty would protect homeowners if something went wrong. When our tankless water heater failed, I learned how difficult it actually is to access that warranty.

Navien refused to communicate with me as the homeowner and would only speak with licensed contractors on site. To pursue warranty support, I had to hire a plumber, an electrician and a general contractor—not primarily to repair the unit, but simply to act as intermediaries with Navien. They spent hours on hold, repeating basic troubleshooting steps, taking photos, and submitting documentation.

Despite this, Navien repeatedly deemed the information insufficient and imposed additional, sometimes contradictory requirements. Promised callbacks did not materialize. Documentation submissions were rejected or routed into procedural dead ends. Instead of progressing toward resolution, the process repeatedly reset.

In total, I spent more than five contractor hours and over $500 simply trying to access the warranty. Only after significant escalation did Navien agree to replace a single internal component rather than the unit.

The issue is not that a part failed—it’s that the warranty process appears structurally designed around contractor gatekeeping, prolonged delays, and escalating procedural hurdles that shift cost and effort onto the homeowner.

After reading other customer accounts, it’s clear this is not an isolated experience.

My conclusion: Navien may sell advanced products, but their warranty is effectively out of reach for most homeowners. If you are considering Navien, understand the real risk may not be the hardware—it may be the process required to make the warranty usable. I'll not make that mistake again with Navien.