First Post Introduction / Navien NFB boiler or combi experiences? / Boiler Favorites?

Teemok

Hello everyone. My name is T-mo. I've been involved with the hydronics trade for 30+ years. Trained by my uncle starting at 13 as a plumber/pump and well/ heating tech. in Maine. I went to art school but found my passion was more inline with mechanical engineering. Did the first two years of school but ran out of money. I've done some sheet-metal fabrication, Air system design and have been an HVAC service tech for a few stints. EPA certified. I ran my own business for 12 years but hated having to find train and run employees, all the desk work and treadmills that come with keeping a crew working. I'm currently a solo hydronics contractor focusing on service in Sonoma, CA. I love diagnostics and resolving long standing problems with existing system. I like the role of detective and engineer, though I'm neither. I enjoy helping people and being worth what I charge. I can geek out on efficiency and tech but have learned simplicity and durability are very valuable. I've done a few heat pump hydronic systems and want to be on that front for new system design and ground up installs.

Anyone have any experiences with Navien's fire tube boiler-NFB or combi-NFC? I'm not a Navien fan but their fire tube seems good. I have a few in service without any issues. I like the control interface, setup and programing so far. The on board zone valve control option is without end switches and I find that inexcusable but that's my only grip. Yes, it's big but that will make it easier to work on. It has a great turn down ratio and is fairly quiet most of it's firing capacity. My next fire tube choice would be an IBC and then a Lochinvar. Rinnai as a company is good and I like the I series boilers and their tank-less units are good. What's your take? No giannoni's. Yes, I know some are better than others. HTP? Let's not.

kcopp

Never Navien for me.

SuperTech

I like the fire tube Weil McLain boilers. Anything is preferable to Navien. 

Teemok

Weil Mclain- I installed when I was training in the late 80's early 90's east coast. Cast iron nat. draft, some oil fired and some mid. efficiency stuff with that used that questionable dark clearish plastic flue material. I'll check them out. Do you know if they make it themselves, is it a collection of others parts or a label change rebrand of another maker? At first glance: 5:1 turn down ratio ??? I'm in a warm climate with customers that want to micro zone every little 2000-6000 btu load space with low mass distribution. Short cycle city. I have to insist they don't do that but they have the money. Maybe it has it's place for some systems.

kcopp

I am a big fan of IBC. My go yo the the HC/ SuperFlow unit.
The SL/ VX are solid units w/ a crazy good control.

Teemok

Yes the IBC SL control has a ton of flexibility and features. I think IBC made it. The HC /super flow HX is unique being both copper and aluminum. They are not IBC manufactured they are Intergas. They are ok. I see Rheem owns IBC now. Hope they stay high quality. The block of aluminum hx is a good little buffer against cycling. They had some fan issues years back. I was sure the aluminum fire side hx "pins" would rot away but I haven't found one dead. The older ones I see have the lower hx corroded but still working and well over ten years old.

hot_rod

Mild climates, micro zones, at some point a buffer tank makes sense


Or one of the HTP tank style heaters, 50 or 80 gallons takes care of micro loads

Teemok

You're right. Some times I do that. That was the design move back when Munchkins were new and so cooL with no HX cleaning notice or instructions and they came with primary only piping diagrams. I tried to make some coffee with those HX grounds but they turned out to magnetic.