OT: Buying a Combi-Boiler

[The Funster]

I worked for an HVAC contractor for over 30 years and now work for an HVAC wholesaler. I don't sell the Navien but it seems to be the best of the bunch right now. Personally, I would stay away from them. They seem to have an effective lifetime (around 10 years) which is short for such a steep investment. You can go with a standard size high efficiency boiler and have much better reliability, IMO.

 

[The Funster]

Can someone explain for a dummy like me what a combi-boiler is and why people are replacing them every 10 years.

I have a Weil-McLain that’s 6 years old and I planned on having it for another 15+ unless something crazy happens. Oil and provides hot water as well, is that combi?

I’m on single pipe steam radiators and have no idea if that makes a difference? All this talk of leaks and hard water ruining things has me nervous I’m not aware of an imminent issue.

Weil makes a great steam boiler. Have it serviced every year and you'll get 20+ years from it. Single pipe steam is just that. Steam rises to each radiator and then when the steam cools and condenses it flows back down the same pipe to the boiler. This is not the same "condensing" that is referred to with high effiency boilers. Same principle but a different application.

 

[JohnFSilver]

Hmm.

You have a steam boiler, cast iron heat exchanger with a tankless coil. Keep it cleaned every year and it should make it to 25-30. Combi boilers are high efficiency gas boilers. The ones that dont vent through the chimney and can hang on a wall. Those dont last more than 10 or 15 years. 80% boilers that make "on demand" hot water are called tankless coils. They provide about a showers worth of hot water and have been around for 70 years. The only bad thing is Weil Mclanes aren't made like they used to be, so you need to be good about the maintenance. If you find you want more hot water then have a plumber add an electric storage tank to it and you'll have more than you'll ever need for around $1000-$1500. You're fine, sleep well.

Got me thinking if i need a water softener before the water goes into the boiler. I love the taste if my well water, and my applicanes are fine. I have full house filter, but not a softener.

Wife will kill me if I keep on spending money there.

 

[tykurez]

Hmm.


Got me thinking if i need a water softener before the water goes into the boiler. I love the taste if my well water, and my applicanes are fine. I have full house filter, but not a softener.

Wife will kill me if I keep on spending money there.

Probably worthwhile to get a water test kit or have someone come out and test it. I plan on doing that since the last time we had it tested it was slightly on the hard side

 

[tykurez]

You have a steam boiler, cast iron heat exchanger with a tankless coil. Keep it cleaned every year and it should make it to 25-30. Combi boilers are high efficiency gas boilers. The ones that dont vent through the chimney and can hang on a wall. Those dont last more than 10 or 15 years. 80% boilers that make "on demand" hot water are called tankless coils. They provide about a showers worth of hot water and have been around for 70 years. The only bad thing is Weil Mclanes aren't made like they used to be, so you need to be good about the maintenance. If you find you want more hot water then have a plumber add an electric storage tank to it and you'll have more than you'll ever need for around $1000-$1500. You're fine, sleep well.

Thanks. My only worry with the whole system is the age of the pipes and the quality of my well water. I imagine having semi-regular water tests is also a good idea to make sure nothing dramatic has changed.

 

[Pistolpete]

There seems to be a lot of manufacturers to choose from: A.O. Smith, Rinnai, Navien, etc. I've had a Navien for about 10 years but considering a different choice this time around.

Please contact me. I have worked and for a natural gas utility for over 30 years and been involved in over 500 combo boiler installations. Too much to text email me with your contact information