Navien NHB 150

ben01

Hello

New to the site but have been reading for quite a bit. I am a Plumbing Contractor in Northern Illinois who focuses on strictly plumbing. I have my personal house which we recently purchased and are looking to replace the hot water boiler. I have cast iron radiators and was contemplating the Navien NHB 150 as I install quite a few of their tankless water heaters and haven't had problems, as of yet.

I am unable to find any information good or bad throughout the internet and I'm a bit concerned as the price point is rather low, compared to other units.

The unit has a SS heat exchanger, outdoor reset, and a 15:1 turndown. I can have this for under 2K...

Any thoughts, good or bad? Navien link attached.

Thanks in advance!

http://us.navien.com/Product/Category-NHB series/Page1/Details/30

jonny88

Just my opinion Have installed a few but went a little above required install specs,dirt mag etc.So far so good but will not install one again.Far better units out there in my opinion.Now from a price point when you add everything up your price is as high as the competition on a level above Navien.Again only my opinion but no more Naviens for me 15-1 is impressive though.

ben01

jonny88 said:

Just my opinion Have installed a few but went a little above required install specs,dirt mag etc.So far so good but will not install one again.Far better units out there in my opinion.Now from a price point when you add everything up your price is as high as the competition on a level above Navien.Again only my opinion but no more Naviens for me 15-1 is impressive though.

Thanks! The dirt mag would be a necessity in any mod con install, right? Also, the items needed would be needed on all mod cons.
What would you recommend in a similar price range?

njtommy

i believe the Crown Phantom boiler is in the same price range, but you won't find it with the nice big turn down ratio. Most of the system will be 5 to 1. Water treatment is a must as well as a magnetic filter.
My recommendation for manufacture is buy what you can where your local supply house stocks and carries the all the parts for. Also it's a plus if they offer training on the manufacturer they sell.

Ironman

You won't find Navien parts at the supply house. You must contact their tech support and they will authorize and ship parts directly to you from NJ or CA. Navien trained techs can purchase different repair kits that have the necessary parts for each boiler, then tech support will send them replacements as authorized. They get them out quickly, but what do you do during a breakdown on a cold Christmas weekend if you don't have the kit?

HDE

Ironman said:

You won't find Navien parts at the supply house. You must contact their tech support and they will authorize and ship parts directly to you from NJ or CA. Navien trained techs can purchase different repair kits that have the necessary parts for each boiler, then tech support will send them replacements as authorized. They get them out quickly, but what do you do during a breakdown on a cold Christmas weekend if you don't have the kit?

Bob, That's not true. Navien distributors may and many do stock parts purchased directly from Navien. These are sold as either warranty or stock. If you know of a Navien distributor that does not stock parts, you should be asking them why. This of course tends to be an industry problem and sets apart the better distributors from the rest. Some are just better with parts than others.
But who here hasn't stocked parts for products that they install in case of emergencies? If not, why?

Ironman

Well, if it's not true, then you need to tell your tech trainer that, because that is exactly what he told the entire class and the reps confirmed it.

Harvey Ramer

It is and has always been the wholesalers job to stock parts for the products they sell. Not the contractor.

Ironman

Harvey Ramer said:

It is and has always been the wholesalers job to stock parts for the products they sell. Not the contractor.

I agree Harvey, but they told us that Navien went that route because entirely too many in warranty parts were being returned that weren't bad. That's what happens when you sell to plumbers who don't have the technical knowledge to service the product. They just start changing parts hoping to get it right because the customer wants it fixed immediately - and rightfully so. This way, you have to call tech support and get them to determine what part is bad and authorize a new one.

I'm not knocking plumbers - I are one. But hardly any plumbers down south, and few HVAC techs, have any clue as to how to diagnose a mod/con.

njtommy

Ironman I though "down south" all you guys had where heat pumps. Lol. I'm kidding.

I looked into a few brands before I installed my Combi boiler, but everyone who sold Vessmen or Weilmclain told me parts would be a day away if I needed any thing. I looked at Triangle Tube and Navien both located in southern Nj about 30 mins from me. Crown is in Pa, but the phantom boiler was not out yet.
I ended up with Navien due to the supply houses at work I deal with on daily basis don't sell triangle tube.

jonny88

Mod cons in general need to support the guy in the field.If supply house sells it they should have any part necessary to fix it.Its not accept table to tell homeowner who is relying on boiler that heat and hot water will be fixed when company ships part to supplier.Whats the wait 2 days?You will always hear I never had this problem with my old cast iron boiler.My former company that I worked for had a problem with a Veissman.Control board was bad.My old boss had to shell out 3500$ to buy new control board before they would accept defective board.Its not only Navien that has problems.Moon is turning red enjoy the spectacle

4Johnpipe

Be mindful of what your current boiler supply water temp is set at. Mod cons have a max temp of 194 or 195. Cast iron rads and associated piping typically have a lot of volume of water to heat up. You may want to consider a buffer tank with a mod con. HTP makes a Pioneer that has 55 gallons of mass and up. It will come in higher in price but it is much more forgiving for older system piping. Also perform a thorough heat loss taking into account as much of the building envelope / construction as you can.

njtommy

The Higher Price tag for an HTP is not much more once you sit down and figure out pricing on the following
Extra pump for Primary loop
Valves and pipeing for primary loop along with added time of install.
The main cost is the buffer tank
It all adds up quick.

Not sure he would need a buffer tank if the boiler fires down to 10,000 btus, It's still a possibility.

Have you done a heat loss calculation yet on the house?

Sal Santamaura

I think it would be interesting for Navien video celebrity Dave Yates, who doesn't seem to have posted here ("GrandPAH") in quite a while, to weigh in on the NHB parts support situation. I'd also appreciate hearing more detail from Dave about the NHB's heat exchanger design and its maintenance requirements / susceptibility to crud buildup.

njtommy

Crud build up needs to addressed no matter what style heat exchanger. Water treatment is probably more over looked then any thing else in the system or design.

sokol

Installed the smart zone 6 controller. Keeps turning relays for zones and zone pumps on and off. Doesn’t stop. Just keeps clicking and clicking. From the initial start-up. I have two air handlers with circ pumps and an indirect water heater. Any ideas anyone ? about to throw it out and buy a Tekmar. It was supposed to be plug an play. So we reconnected everything through a relay again and now everything works. Please help.

sokol

Same pic hopefully in focus. Tried posting a video of it clicking back and forth.

njtommy

@sokol what kind of t-stats are you using? And does it do it with the wire pulled going to the t-stat?

bob eck

4Johnpipe said:

Be mindful of what your current boiler supply water temp is set at. Mod cons have a max temp of 194 or 195. Cast iron rads and associated piping typically have a lot of volume of water to heat up. You may want to consider a buffer tank with a mod con. HTP makes a Pioneer that has 55 gallons of mass and up. It will come in higher in price but it is much more forgiving for older system piping. Also perform a thorough heat loss taking into account as much of the building envelope / construction as you can.

Take a look at Vaughn hydronic buffer tanks 10 - 20 - 30 - 40 - 50 - 80 - 100 - 120 gallon size tanks available.
With a buffer tank you get your primary secondary piping plus you add water volume for systems like baseboard or ductcoil systems that will help the boiler from short cycling giving the boiler longer run times.
You can also get the Vaughn buffer tanks with 1 or 2 coils in the tank.
With one coil in the buffer tank during the heating season you could run your domestic water through the coil to preheat the domestic hot water before going into the combi boiler.

bob eck

If you want to look at another condensing boiler take a look at the Lochinvar Noble combi boiler.
High efficiency 95% AFUE
Stainless Steel fire tube heat exchanger
10-1 turn down with outdoor reset
Vents with PVC, CPVC, Polypropylene or SS
Proper venting is very important. Cross contamination pulling exhaust vent fumes right back into the boiler instead of clean fresh air will kill the boiler.
Blazed Plate heat exchanger for domestic hot water (can use the boiler as a heat only boiler)
Easy to read boiler display and easy to change parameters
Boiler has primary pump, control runs one more pump

Water quality is very important. Some systems need chemicals to clean out the old system and more chemicals to keep system clean.

Should install a good dirt separator / dirt magnet from Caleffi or Fernox there are others.

www.lochinvarnoble.com