Shop Products
Houzz Logo Print
rickyk22

Navian condensing combi, good or bad?

rickyk22
10 years ago

Hi,

I am looking into converting from oil to gas and it was suggested that I get a navian condensing gas boiler/water heater. I was wondering the pros and cons to this as opposed to a boiler with separate water heater. also, how are the navian boilers? any other brands I should look at and is a condensing boiler what I want?

Thanks for the help.

Comments (127)

  • canadave
    8 years ago

    I received the heat loss report which said that the house requires 55,000 BTUs and that's for the whole house of 2,800 sq. ft. It did not break down upstairs and downstairs. The pool room requires 38,000 BTUs. Since the pool requires 210,000 BTUs, the Navien 240 Combi which only puts out 120,000 BTUs, is 90,000 BTUs shy of what's required for the pool alone. I'm going to install the Jandy 260,000 BTU boiler for the pool and pool room so the Navien can concentrate on the house and domestic water. If the contractor knew what he was doing he should have installed a smaller, assuming there's a smaller one that would heat the house and water. The difference in cost between a smaller one and the 240 may have covered the cost or come close to the cost of the Jandy JXi LO NOX 260,000 BTU pool heater.


    which will cost $1,869.00 or $2,112.00 Canadian after tax. Being one hell of a nice guy I had earlier told the contractor that I recognize the possibility of the boiler being too small in which case I was willing to pay the difference between what I bought and what I should have bought (or is that botten?) which is the price of a pool heater. I didn't have to do that since by law here in Ontario he has to deliver what he promised and he has to do whatever is necessary to do so at his expense. I had another quote which was $1,700 more and included a 230,000 BTU boiler which should have worked for the house and pool but not the domestic water. Had I gone which that quote I should have been fine but I would still have to use the electric water heater. For what it's worth my hydro bill has dropped by $100 per month since that electric water heater is gone but I don't know how much I'm paying to heat the water with propane using the Navien 240. I suspect it's still a huge savings and I'm probably better off with it and a pool heater. I'm also going to blow some insulation into the attic which I'm told will pay for itself in two years at the most and result in less demand to heat the house. Wouldn't it be nice if everything in life was simple and obvious? By the way the Canadian buck has gone from par to 70 cents U.S. which means you should come up (or down if you live in Alaska) and buy lots of crap here and save a bundle. I pity the American folks who bought a cottage here three years ago instead of now when it costs 30% less.

  • canadave
    8 years ago

    ionized_gw

    "If you want to get a better grasp of your savings, get local weather information degree days. Divide gas dollars, therms or cubic feet by degree days for a periods before and after the boiler change".

    That sounds a tad anal to me but what do I know; I'm a technopeasant and have no idea what you're talking baout.

  • canadave
    8 years ago

    I mean about or aboot as we say in Canada.

  • ionized_gw
    8 years ago

    gamma888, You have what might be a tough problem matching a mod con to 7 small heating zones in a mild climate. I can't imagine not having a short cycling problem if you have a boiler that will provide enough hot water for you unless you provide a buffer tank. I am not a pro, however, so I could easily be mistaken. There are some enthusiastic boiler/hydronic heat experts at terrylove.com in the boiler forum and at heatinghelp.com.


    Keep in mind that in your mild climate, there is little payback in the highest efficiency heating and cooling. That is especially true in new, well-sealed and well-insulated construction. Make no mistake, the HTP are high tech condensing, modulating boilers. They use a very different type of heat exchanger that, I believe, use the natural temperature-based stratification of heating water to set up a counter-current heat exchange in the tank. This is compared to narrow tubes in the Navien and countless others.


    Do you have heat loss calculations yet? There may be a way to save some coin and get an HTP-like boiler. HTP manufactures a Phoenix light duty water heater based on the same design, but it has a 3:1 turndown ratio rather than 5:1. There is no secondary heat exchanger (to link the space heating) so the contractor would have to add this rather then use a built in one like in the Versa Hydro. Westinghouse sells the rebadged water heater for a nice price. The WGR080076 is the 80 gallon model (50 and 60 are available). All of them are 76 kBTU max. That compares to the 130-199 kBTU of the Versa Hydros. Available heat output for space heating is 25-30% of that total rated capacity due to lower temperature water after the heat exchanger.

  • Maddie Whitfield
    8 years ago

    After reading every comment in this long thread I've decided to go ahead with installing the Navien 240 combo unit. About 3000 sq ft, heated with hot water rad fin system, and one room Infloor heating with 2 adults and lots of guests. After rebates paying about $10,500 Canadian, taxes in. Since most of the problems I've read about tend to happen soon after installation and seem to surround the installation, I've made sure I have a written 100% satisfaction guarantee for one year in addition to all the Navien warranties. Our boiler installers are manufacturer trained which should be the best available. I will post the before and after and let you know about any issues to help those still deciding. Due to our current low dollar things are much more expensive here, but others can figure this into other dollar amounts.

  • Tony D
    8 years ago

    Installed a Navian NCB-240 propane unit in November. Replaced a 25 yr old oil boiler. I'm estimating a $500 to $1000 cost saving per year on fuel. House is well insulated with a size of 3000 sq ft.. It has 4 zones of baseboard convectors of relatively the same length. Cost of materials (not including labor) were about $5000. It is in condensing mode most of the time. Efficiency is probably 90 to 95%. I am very satisfied with the unit.

  • ionized_gw
    8 years ago

    Tony D, can you find the efficiency at any particular moment or average over a time period by pusihing the right buttons on the control panel?

  • PRO
    New England Nest LLC
    7 years ago

    Good thread. Would appreciate comments on my HVAC situation. Renovating 3 family home in Boston area. Cold winters/hot summers. Each unit 2 beds, 1 bath, in-unit laundry approx 950sf. Home is currently one zone FHW by oil to radiators. No AC. House has gas and 3 HW tanks. The plan is to remove oil and radiators; replace w hydro air and AC. Incorporate HW in system or keep tanks. Space on each floor at premium. Have basement and attic. Getting to 2nd floor is tough. Like idea of suitcase-size boiler to hang in unit pantries, soffit above cabinets and along center wall for ducting. Navien/Combi being discussed for heat and HW with Comfort Aire for AC. Here are my needs: efficient, dependable, space-saving, easy to maintain, rebate applicable, high E, warm in winter, cool in summer, lots of hot water. Is this best solution? Budget: $30K.

  • ionized_gw
    7 years ago

    If you can find a boiler that fits the heating demand and DHW demand, it will work. If not go another route. You won't get real efficiency or good service life from an oversized ModCon.

    Why not install a furnace and a water heater for each unit. Space is too short?

  • PRO
    New England Nest LLC
    7 years ago

    I thought these units were made for smaller spaces like my rentals? Space is plentiful in my basement where we have water heaters for each unit. I can install three furnaces in the basement and then duct from there. But it's tough to get to the 2nd floor. Space in the unit is too tight to put the mechanicals in the units. One contractor suggested using the abandoned chimney to get to the 2nd floor then reach the 1st floor from the basement and the 3rd floor from the attic. Is this a better option?

  • ionized_gw
    7 years ago

    OK, I understand the access problem in installing ducts from the basement. Hydro air coils in an air handler might work better since you only have to run pipes.


    Are these units built for smaller spaces? You need heat loss estimates to know if they "fit". You have to be careful of hydro coils and high efficiency boilers. Hydro air coils generally "run" at a pretty high temperature. To get anywhere near the max efficiency of a condensing boiler, the return water temp should be low. IIRC, you want 130F. In order for a hydro air coil to work at those temperatures, it may have to be prohibitively big to put in the tight-space units. Your heat guys have to know their stuff to put this all together.

    If you can't make the coil big so it has to run hot, you are better off getting the minimum efficiency boiler allowed in this day and age. They are less complicated boilers with less stuff to break and less maintenance.

    You really want to stay away from outdoor ducts. That means stay out of the attic and stay out of chimneys. Ducts leak. Leaking ducts turn your HVAC system into a power vent blowing air our and sucking it in from very random places wherever you have a small opening in the building envelope.

    Is this going to be very well insulated and sealed building when you get done with it. If so, you don't have to worry so much about efficiency. Take a look at this article, nonetheless. Heat pump mini splits might be the thing for you. Do you have essentially three open areas to heat?

    Long-Term Monitoring of

    Mini-Split Ductless Heat

    Pumps in the Northeast

    Building America Report - 1407

    December 2014

    Kohta Ueno and Honorata Loomis

  • PRO
    New England Nest LLC
    7 years ago

    I did consider mini splits but decided against them. They have not been fully embraced in the New England and are better for retrofitting AC for summer homes. Some folks don't consider them full systems and we might condo the units. Also I will need three per floor to get the bedrooms. So I'm back to HVAC using Carrier furnaces in the basement and keeping hot water from tanks OR trying the hydro air condensors with a real pro. The problem with hydro air is the space it takes up in the pantries and the soffiting. I'll talk to the HVAC and plumber who are proposing the systems. This is an older home and we have not started reno yet. I don't know what is in the walls. We may have to blow in some insulation. It seems pretty tight to me. I close on the home next week so it's a new property for me and not sure what goodies await us. I'm trying to do this for $30,000. The hydro air is coming in at $10K per floor w Navien and Comfort Aire. The HVAC is a bit more. But this using chimney and attic unless we can find another way up or down w ducts.


  • gen7accord
    7 years ago

    Anybody hear about the IBC DC 33-124?

    Thanks in advance.


  • smppix
    7 years ago

    I've just read through this entire thread and find it quite interesting. I grew up in Canada, moved to the USA and then to the UK, where I've now lived for almost 20 years.

    We have a small (1200 sq ft) cottage near the Maine coast. It's currently heated (but not used much) through the winter, using a combination of a Hot Dawg (external air supply) propane heater and a gas fireplace (works without power). That's been fine for ten years now, but we intend to make more use of the place in the winter, so I'm considering replacing the Hot Dawg with something a bit more sophisticated (and quieter). If you don't know the Hot Dawg - it's essentially one of those things you see up in the roof of Home Depot pumping out hot air in the winter. Simple, reliable but a bit noisy.

    Although a heat pump is attractive, what with the "free AC" thrown in, they are quite expensive in Maine. A unit that costs $1000 in the UK (Panasonic, LG, Fujitsu) somehow becomes a $3000 unit in the USA. My sister in Canada has a heat pump (split unit) but it was subsidized by the government and their electric power rates are half of Maine (in the top ten for electric cost in the USA). It also quits working at about -20C (~0F - about as cold as ever seen at our cottage, but a consideration).

    Now, I'm very familiar with the "combi-boiler" option. I've had several in different houses and have arranged the installation myself (using pros, of course) so the loads and layout were designed solutions. I've done both mains (natural) gas and LPG. One system was a true combi (on-demand hot water) and the other a boiler with a "Megaflow" DHW heater heated by an immersion loop (plus electric backup).

    A decent small (12KW) combi-boiler is about $1500 in the UK. Installation would add about another $1000, depending on access. It's perfectly feasible to go down to the building store, by a boiler and some radiators, hook it all up and then call a "gas certified" engineer to do the gas line connection, check your installation and fix any errors you made. It is such a common situation there is none of this "that's my protected business" that seems to double the costs of both heat pumps and central heating in the US - but that's just an observation. I installed my Hot Dawg and gas fireplace myself and the local LPG supplier hooked it up for me, so I assume the same can be done (at my rsk) with a combi-boiler.

    The "best" name for gas combi-boilers in the UK is Worcester-Bosch (Greenstar is a sub-brand). They come tops in all the reliability surveys (keep in mind 90%+ of 60 million people will be using this type of heat, so the feedback is sound). Vailant is a notch below. Glow-worm is a Vailant sub-brand.

    Worcester-Bosch has a five-year warranty with a ten year heat exchanger warranty. Many of the older non-condensing models went 20 years (often without a service) but when regulations mandated condensing boilers the reliability dropped off sharply. Much of that was due to poor installation practices. Although it doesn't get that cold in much of the UK, it still drops well below freezing for weeks at a time and there were many problems when condensate drains froze up and then disabled the boiler (failsafe). Of course, the condensing boilers are much harder on their heat exchangers, so newer units are better designed.

    I've yet to find any good reliability data for combi-boilers sold in the USA, but Bosch does offer units, so I will have to compare costs and guess. A small 12KW Bosch combi in the UK is perfectly adequate for a small (800 sq ft) two-bed/two-bath apartment with minimal insulation and an average winter temperature of around 40F. The DHW provision is enough for two showers at the same time (domestic dishwashers and washing machines in the UK all have only a cold water feed and heat their own water). That's using natural gas, which provides less heat than the LPG in another (larger) house. So I am guessing 15KW is probably about right for our cottage.

    BTW, rather than try and "zone" heating in the UK, the radiators (at least in smaller homes) are fitted with individual thermostatic bypass valves. The valves react to room temperature (quite crudely, but effectively) so the heating is one continuous loop and the radiators cycle themselves on and off as required. Bathrooms are heated by a "dual fuel" towel rail. That's a large chrome radiator in the shape of a towel rack. Hot water circulates through the rack, drying your towel (and keeping it toasty warm) while warming the bathroom. (In the summer, you can have timed electric heating for an hour before your shower).

    The DHW at our cottage is now simply a Home Depot 40 gallon electric hot water heater. I think it was $300 ten years ago. Electric consumption is about $25/mo unoccupied (mostly the fridge and the electric company's standing charge) which zooms up to $50/mo if the cottage is occupied and hot water is in use. Propane costs about $1000/yr - that would be at least doubled if the cottage was occupied in winter, but it puts the cost of any replacement heating system in perspective.

    I have some choices to make over the coming months but have the benefit of no pressure - if it doesn't happen this year, the Hot Dawg will keep the winter at bay. I'd be interested in any comments regarding combi-boiler installations or choices and experiences. As mentioned, it's a small cottage so a compact heating system has its attractions and LPG is already available on-site.







  • Kerry Kennedy
    7 years ago

    Bad. We had a new Navien installed in August 2015 and the piping configuration, reconfiguration, and re-install (including an entirely new machine being shipped by Navien) took over two months.
    It errors about once every 10-12 weeks. Resetting it works 75% of the time; otherwise we have to shut it down completely and restart.
    The error code is typically E.110 which I can't even find in the error codes online.
    Came home from a week away in January to a 53 degree house because it error'd and nobody was home to reset it. It also happens when in the shower and suddenly we are stuck in frigid water, have to get out and walk down to te basement in a wet towel to reset. Total waste of money. We just called the company that installed it for us to come back and replace with something else.

  • plegra97
    7 years ago

    I have a hard time believing there could be so much variation in quality with the same exact product. Obviously there are always going to be a few dud units here and there but the main variable with these systems is the person who does the installation. I'm not a plumber by any means, but just looking at the complexity and amount of plumbing that goes into installing the Navien or any other tankless system seems massive to me. If you get the wrong person installing your system it could make a huge difference.

    I have had my Navien for a little over a year and I couldn't be happier. Literally, not a single issue since installation. I lost hot water one time and when I checked the error code it was because the unit wasn't getting any natural gas. Turns out my gas company had shut my block off to do some maintenance. Everything was back working perfectly as soon as they turned it back on.

    About 3 months ago my father converted to a tankless Bosch system because the installer said it was a superior product. From the start nothing worked properly. He had them come back numerous times to check it and finally the owner of the plumbing company came and saw that the installation was done wrong. They redid their work and so far it's been fine.

    In my experience, the product works great, saved me a decent amount of money this past winter, and is unbelievably clean and space friendly. Just make sure you get the right person doing the installation and I don't think you will be disappointed.

  • Rick
    7 years ago

    I've had mine for about a year and a half and have been happy with it. I did have a few issues in the beginning with an error, but they replace a part and its been good ever since. I started this thread and i am sure you can read back my experience from the beginning if you'd like. I too agree that it needs to be installed with a qualified plumber that has experience with these systems.

  • smppix
    7 years ago

    Thanks and yes I have read all the way through - Just had my Worcester-Bosch 24KW LPG boiler serviced yesterday. Third year without a hitch. The Vaillant before that blew up (yes, literally) through a combination of a failed seal (they kept trying new versions) poor documentation (the installer never registered it, so the company couldn't inform me directly) lack of publicity (who wants to brag their boiler blows up?) and minimal servicing (my bad, but it was serviced twice in five years with minimal use). So I'm a bit off Vaillant for the moment.

  • speedracerxyz
    7 years ago

    Thank you for all the pro and homeowner posts on here regarding Navien boilers. Super informative.

    Like many here I have 45+ year old cast iron oil burner in a tenant's unit costing roughtly $200-$250/mo in heating costs for a ~600 sqft apartment in the southern CT. Just had 3 contractors come back with wildly different estimates on replacement:

    1. Cheapest: removal of monsterous cast iron beast and install of a Navien NHB-80 for ~$3k.
    2. Another @ $6500 for a much nicer Weil-McLain CGA-3 (but w/out removal of the old cast iron).
    3. A third spending a good deal of time suggesting I not replace the cast iron boiler at all, but rather consider simply updating the "guts" of the beast and retrofitting it with <something I cannot recall at the moment> to dramaticlaly reduce the overall energy usage of the furnace.

    I know it's old hat for the pros on the thread, but for those outside the field curious about all these differences in technologies I found WP's overview of condensing boilers quite informative for a newbie.

  • ionized_gw
    7 years ago

    3. is probably replacing the oil burner (AKA gun) with a gas burner. This would shift to less expensive fuel, but not improve the efficiency of the system much if at all. It may not be a wise investment in a boiler that old, but if you are planning on selling the property soon, it might be the way to go. Beware, however, that to do this right, the chimney might require modifications or replacement. Stack temperatures for gas are lower than for oil and you could end up with condensation and deterioration of you existing flue/chimney.


    The Navien will require a new flue arrangement since it is a condensing boiler. It looks like the CGA-3 is not so you might be able to get away with the existing chimney, but it has to be examined by someone that knows what they are doing.

    Insist on heat loss calculations and heat exchanger (radiator/convector) calculations to match the boiler to the rest of the system. if the radiators can only output 50 kBTU, the Navien won't be able to use it. The NHB-80 seems very large to me for a little apartment unless it has many leaky windows and no insulation. The NHB-55 is probably a better match and it is close to the capacity of the WM. (You have a conflict between the two contractors there already.) Yes, both Naviens modulate to the same minimum output, but the bigger one may not run as efficiently unless the highest fire can be locked out.

    What are you doing for domestic hot water?

  • Val V
    5 years ago
    Curious for an update from those of you who commented here a couple of years back. I'm scared to death to have my plumber install a Navien Combo after reading this thread. I recently purchased several beautiful Runtal baseboard radiators and the plumber is using the Navien Combo mainly because that's what he has been trained to install. My house is about 1,500 sq. ft., 2-story, total rehab and so this will be a new system. I've been trying to become knowledgeable about Navien through reading threads such as this one. Any further insights would be helpful and appreciated.
  • lbnyc123
    5 years ago

    We've had ours for 3 years now. While it works well, we've had 2 breakdowns mainly with the motherboard. It was switched twice. Thankfully under the warranty but still annoying to have it happen every year. Not sure if I would have spent the amount of money we did and have this happen. We're hoping for an issue free winter this year. Our house is about 2300 sqft.


  • nepool
    5 years ago
    I love mine 4 years later - no issues!
  • plegra97
    5 years ago

    Just past 3 years for me and haven’t had a single issue. I’d say I’m saving anywhere from $700-1000 per year in costs so it’s def been worth it for me.

  • HU-722480012
    5 years ago

    I am planning to upgrade my mid efficiency boiler (Slantfin) to either a Bosch Greenstar boiler or combi boiler, or a Navien combi boiler.

    Last Dec (2017), I received two quotes to install a Bosch, about Cdn $11,800 to $12,000.

    In Sep 2018, a different installer indicated that a Navien boiler will cost about Cdn $5,900.

    Earlier today, they came to take a look, and will provide a quote for a Navien combi boiler.

    A few of the above reviews indicated that a Navien boiler will last about 5 to 7 years.

    My current Slantfin mid efficiency boiler is about 16 or 17 years.

    Any suggestion whether I should install a BOSCH Greenstar boiler or a Navien boiler?

    Thank you.

    in Toronto, Canada

  • HU-200803034
    4 years ago
    last modified: 4 years ago

    JPW

    I purchased a Navien Model 240 three years ago. I continued my service contract that I had on my old system. That contract has now increased to $439 a year. Is it worth paying this every year on a new heating system or just call for a service call when necessary.. I feel like I am wasting a lot of money each year as I have had absolutely no issues with the system. Any thoughts appreciated.

  • Hawk3ye Hawk3ye
    4 years ago

    @Maddie Whitfield did you end up purchasing a Navien combi-boiler? How has it gone? Any issues with installation or maintenance?

  • David Cameron
    4 years ago

    My Navien 240 combi is now 4 years old. The only problem i have with it is that periodically while running a hot water tap it suddenly gets cold for a couple of minutes before getting hot again. As I mentioned earlier it was insufficent to heat the house and indoor pool but that was because the contractor recommended the wrong heater being the combi which produces only 199,000 BTUs which is more than enough for the house but the pool should have at least that much. I ended up getting a New York Thermal 250,000 BTU boiler for the pool which has been working flawlessly.

  • okrom1234
    4 years ago

    My 2 Navien combis were purchased 5 and half years ago. One is working flawlessly. The other gives me a lot of problems. I have changed several components . The problem is the constant error code EO12 FLAME LOSS. MY tech has called the company countless times and replaced many parts, yet the problem persists. Now the tech support says I should change the ignitor. How do I get Navien to replace the boiler? I am really tired of this boiler. Several times a day I have to go down to my basement to reset it.

  • David Cameron
    4 years ago

    I'm feeling a bit nervous of one of the comments here is true that a Navien will only last 5 to 7 years

  • HU-459600872
    3 years ago

    I know this is an old discussion, but wish more owners of Navien Combi system could update their experience.

    I have a triangle tube boiler installed 10 years ago, which worked well for the first 5 years. Now it has required so many service calls, and we have changed motor fan, control panel, ignitor, expansion tank. The machine itself looks in okay shape, but the frequent service calls are quite expensive, so I am thinking to replace the unit.

    One of the plumbers recommended Navien combi system, saying that he has gone through company training and he has done over 20 installations last 2 years with good luck. As two year is not an extremely long time, I would greatly appreciate if anyone can chime in and update their experience.

    Thank you!

  • orionto
    3 years ago

    In BC, Canada, feels like a lot of the contractors are recommending Navien Combi 240. Would love to hear from people who had it for over 5+ years, and whether they recommend it or not.

  • Justin Thomas
    3 years ago

    I just moved into a new home that had an old

    mold Navien 240. This is a small home built in 1850. It was installed in 2012. so about 8-9 years old. Since, we just purchased the home and I was not experience with these type of systems. I had a professional certified through Navien to service the system. I live in MA and have lived in the house once December. We have had no problem and the benefit of having endless hot water is awesome. Traditional hot water heater in my old place in the winter would kick you out the shower with cold water pretty quickly.


    I got side tracked.. back to the servicing. The plumber looked at the system and noticed corrosion coming from the heating mechanism casing. He had me turn the hot water on through out the house. He captured video of the a dripping coming from the case. He called Navien and is getting a full replacement approved. 8-9 years into the 10 year warranty they have on the systems. That does not include labor however so be wary there. Even still to get my old model replaced with their newest mode 8-9 years later with the previous owners having no record of maintenance. It was previously a rental property. I personally will be happy with that outcome. The plumber gave me a kind of wisdom with these types of systems. Basically, servicing yearly is imperative unlike other systems which can be more hands off. Like others have said these systems have so many components that can cause problems. He also may say about any system he installs to get the service calls, but from what I read that seems to be the case.


    Either way, this system has lasted since 2012 without proper maintenance. Navien is replacing the system through warranty after that amount of time. Overall that seems pretty good to me. Just sharing my experience since but I am in no way a professional on these and have limited experience overall With the system. Heats our 1000 sq ft home well and love the no limit hot water. I probably ruin the whole green planet stand point .. but I will try to get better aha.

  • Justin Thomas
    3 years ago

    I spoke to soon on the warranty. They are now denying the claim for lack of maintenance and the use of iron pipes without a separate "navi clean" system. I am not even sure if that was around during the time of this units installation. I am working with them now and hopefully they give some remedy on this. It seems as the Ch-240 has plenty of issues with the heat exchanger. Will update as we go.

  • orionto
    3 years ago

    Keep us updated! I ended up going with Viessmann VITODENS 100-W + IBC Indirect Water Heater in BC, Canada.


    Hopefully it lasts!


  • Peter Gill
    2 years ago

    Hi everyone. I am building a new home. My plumber was originally suggesting a viessmann in my home. I have 7zones for in floor heating plus my domestic water but now he changed his mind and told me to install a combi boiler from navien. Reading all these comments I'm hesitant to install a navien. I was originally going to install a viessmann boiler and a 65gallon holding tank. The reason for the holding tank is so I don't lose water pressure during showers. My house 5400sq. I'm on BC so the winters are not too bad. Has anyone else had any issues with navien.

  • David Cameron
    2 years ago

    You won't need a holding tank for showers. I've never had an incident where I ran out of hot water. Oh wait a minute, that's not true. Periodically when I'm running the hot water it will suddenly stop for a minute or so before it comes back on again. I don't know why. Fortunately it has never happned in the shower. I've had my Navian combi for about five years if my memory werves me well and it's working fine.

  • Peter Gill
    2 years ago

    The reason why we were installing a holding was because our plumber recommended it due to our house size. We thought about a tankless unit but he didn't recommend it but now he saying the new combi navien system came out and it produces 220000 btu. Not why he changed his mind. At the end I just want to make sure the unit I install will enough for a family of 4. Never had in floor heating either.

  • littlegreeny
    2 years ago

    I would seriously reconsider installing a Navien. Watch this video:


    https://www.youtube.com/watch?v=CjdIjA1ZznY&t=1s

  • Peter Gill
    2 years ago

    Thanks for the video. I am definitely not installing a navien. I hope viessmann won't be a problem.

  • userchooser
    2 years ago

    Very informative thread. Thanks to all for posting. Littlegreeny, I was not able to view the video, as it comes up as "private" and one that you need persmissions to view. Can you provide an overview of what the video contains?


    I too am anxious to hear from Navien boiler (combi &/or gas only) owners in that 5 year and beyond range to see how they've been fairing with their units. Ninety eight percent of the installers in my area have suggested I get a Navien wall hung. But, after reading this and as well as the many, many other posts from professionals on other heating help forums/HVAC help sites saying beware of this brand, I question these suggestions. I am very concerned about what replacement brand I should get. One thing I know for sure is, I will put in a gas only wall hung with indirect tank (or traditional HW tank), as all the pros seem to be in agreement on, instead of a combi.

  • littlegreeny
    2 years ago

    HVAC Pro Mikey Pipes posted a video showing leaking heat exchangers in the Navien boilers. He posted a number of these videos and last I heard he was getting pressure from Navien to remove the videos. He must have gotten an order to take them down.


    https://www.youtube.com/c/PipedoctorNet/videos

  • Jesse Ross
    2 years ago
    last modified: 2 years ago

    We’ve had the navien ncb-240 for 8 years now and its still going strong! we repalced our 50+ year old oil system. we were paying $300 per month, year-round for oil. we live in new england, 2,000 square feet and built in 1906. We’re family of 5 and Our gas bills are $20 a month in the summer and never more than $300 a month in the winter and i keep the house at 70°. I can run the dishwasher, washing machine, take a shower and heat the house and the water is consistently burning hot. We’ve not had any major issues with navien, we did just replace one part for $30 plus service for a total of $95.

    With oil we had to have a service $350 contract for oil delivery and maintenance.

    I believe we paid around 8k for installation/ gas conversion... worth every penny!


    found this thread trying to see how long these systems last. scrolled and saw the comment claiming it would never last more than 7 years and blah, blah, blah.

    wanted to add my .2 cents to ease any fears to the new navien owners! they do work and work well!

  • Bastroni
    2 years ago

    Our Navien is about 4 years old. Needs a new heat exchanger which Navien will warranty. The labor, however, is over $3200.00 to replace the heat exchanger. We're not excited to spend that kind of money based on all the bad reviews of these units to begin with. Has anyone ever read through the reviews on BBB? Yikes..

  • Suzan
    8 months ago
    last modified: 8 months ago

    We have had nothing but problems with our Navien NCB-E combi boiler. it worked well for about five years. as soon as our warrenty expired we started having major issues. it has now cost us over $4000.00 in parts and labor never mind the stress and aggravation.

  • David Cameron
    8 months ago

    Our Navien combi only lasted about two years and was so bad it could not be repaired for less than a new one so I replaced it with a Bosche which my research indicated was the best

  • Glenn Sivertsen
    last month

    I own a Plumbing and Heating company in Northern NJ and I have Installed many different types of Tankless water Heaters and Combi boilers over the years and all I can say is They all save you money on your utility bills and yes they all have their quirks with them. The number 1 reason for failure with any of the units are lack of service. These units require yearly cleanings and flushings and must be done or you will have a problem. These units WILL NOT last as long as an older style cast iron boiler. These Combi boilers will only last 15-20 years if properly maintained where a Cast iron boiler should last 25-30 years. The combi units are less expensive then a high efficiency free standing boiler with a 40 gallon Indirect water heater, can be up to 96% efficient and you also get a large rebate back from your utility company. If yomaintain them, look to get 20 years out of them.

  • HU-350097384
    3 days ago

    I have a Navien combo unit, installed slightly more than 7 years ago. ive also kept up with the yearly maintenance. i recently noticed moisture on my basement floor and called the installer i was told the coil is corroded and it’ll be $1000.00 to replace. he also suggested that i could replace the whole system. I find it unacceptable that a 7 year old system has a corroded part that only has a 5 year warranty. personally i would not recommend Navien.

  • fsq4cw
    2 days ago
    last modified: 2 days ago

    START YOUR OWN THREAD - THIS IS ANCIENT & DORMANT!

    It’s not Navien that’s likely at fault. It’s likely your installer that lacks the knowledge and understanding to properly install this boiler to your EXISTING and deficient system. The 1st thing they’re missing it seems, is a proper knowledge of water chemistry. It seems like the right chemical inhibitors, additives and monitoring were not present to prevent corrosion. The distribution system should have been completely flushed and filled with de-ionized water that is less reactive and to have proper automatic dirt and air elimination. The piping of the distribution system needs to properly analyzed and reconfigured for efficient flow and comfort based on heat loss for each room, temperature and flow rate to each emitter with the proper in/out temperature differentials.

    You need a trades person properly trained in modern hydronic installation that understands all the concepts of modern piping - AND someone that is a MATH Wizzard that understands and can do all the proper calculations and then make the changes necessary.

    What you now have seems like a person that’s installed your beautiful Navien boiler like he’s connecting a garden hose to an outside faucet!

    IMPO

    SR

  • Elmer J Fudd
    yesterday

    I very much agree with your "let sleeping dogs lie" sentiment, fsq.

    But your comment triggers a few thoughts. First of all, Navien has developed a TERRIBLE reputation in the US for shoddy designs that cause equipment failures well short of an expected useful life. Sometimes after just a few years. It's a terrible product line best avoided. There are many good alternatives available.

    Second, maybe filling hydronic systems with other than tap water is practiced where you are, that's not been common in my limited experience. Auto-fill valves with pressure reducers are the standard approach. Tap water.

    Lastly, I don't know if you were serious or not but the math required for all aspects of HVAC contracting is not complicated. It's basic arithmetic, not math. Not much more than what a plumber needs to know when running pipes.