Looking for some opinions on the replacement of my scortched air furnace

[chiggins]

The time has come to replace my scortched air furnace! I have been lurking here for quite a while now and learned quite a bit. There is a great deal of knowledge here and I make it a point to check out the posts daily.

My scortched air furnace is not running well. . . and due to some remodeling we only have heat in the half the house. My bedrooms hovers at around 55. This obviously is not too good in the WAF department. I planned to replace the furnace over the summer during our construction which forced the removal of the hot air ducts to that part of the house. But as usual, I procrastinated, and learn to live with a 55 degree bedroom. An electic blanket helps to manage the WAF.

So my current plan is to replace the furnace with i high efficiancy boiler and then add a wood boiler over the summer. I have looked at the NTI boiler as well at the Munchkin and am currently leaning towards the munchkin.

I would consider myself very handy and have done several plumbing heating projects in the past and have run most of the piping already for the new baseboard heat. I am planning to install pex without heat transfer plates under the first floor as an interim until we remodel the first floor. I really don't feel like grinding all the hard wood flooring nails off to install the transfer plates and the basement is my workshop so I am not too concerned about the heat loss that way.

I am attaching my drawing of what I am thinking of doing and would love to hear the good and bad points from the brain trust here. I would also be interested in any feedback on the NTI or munchkin boilers. I am thinking I should probably have someone come and install at least the boiler so that is tuned correctly. I don't mind paying for someone to do the work but I am a bit of control freek and like everything to be nice and neat and I want to understand everything so I usually end up doing most of my own work. It seems good contractors are still hard to find although I am sure they are out there. (and it sounds like a few of them are on this board!)

 

[Eric Johnson]

Welcome to the Boiler Room, chiggins. Very nice diagram. I'll let the experts roadtest it. You'll probably also get some good info on the Munchkin vs. NTI question. If not, they talk about those boilers all the time on The Wall at heatinghelp.com.

I assume you're planning on a gasification boiler. I know we all look forward to helping you explore the various options and alternatives.

 

[chiggins]

Definately looking at a gasifier. I just saw an ealier post about the farm show up in manchester next weekend so I am hoping to get up there and take a look at one running. I have always heated with wood since I was a kid and enjoy cutting and splitting wood. (I know. . . most folks don't think this is fun) I also have a pretty good supply of wood although most of it would be pine. I would be curious about what people think about burning softwoods in the gasifiers. I can either gets lots of pine really easy, or have to work a little bit to get the hard stuff. I am not sure if it will matter much in a gasifier.

-Chris

 

[Eric Johnson]

Oh, we love to cut and split wood around here.

You can burn anything that once was alive, in a gasifier, as long as it's got the right moisture content, which is generally between 15 and 30 percent. They tell me that the EKO, for example, can burn wood, soft coal, corn cobs, wood pellets, sawdust, chips, furniture, cherry pits--you name it. You won't get the long burn times from softwood that you'll see with most hardwoods, but you'll definitely get a lot of heat that can be stored and used later.

 

[chiggins]

That is kind of what I thought. And seeing as I do some work at a camp that has lots of overgrown pine trees that need to be cut down it seems like a match!

 

[solarguy]

Munchkin's are a great little boiler. We've speced them out & I've installed a few over the years
plus they're made in Mass.
If you're planning on a wood boiler later, take a look at the Muchkin Contendor. It's a few bucks cheaper than the m series & you can hang it on the wall. You size this boiler corectly & it'll run at 98% efficient. If your doing a suspended radiant job, just insulate the floor to minimize your downward heat loss & you'll be fine. If you make up to Manchester next weekend stop by & say hello.

 

[chiggins]

I looked at the contender but wasn't sure it was big enought. We have a 3000 sf dutch colonial house. The first floor is 8" block with no insulation and stucco on the outside. The second floor is 2x gambrel with old cement type (likely aspestos) shingles so insulating from the outside is not an option. We are rehabbing each room as we go but right now the heat loss is crazy. We keep the heat at about 60 just so we don't go through too much oil. Not to mention the house has ONE thermostat! yes one for a 3000sf house. We also plan to add a 3 car garage and master suite above so I don't want to get something too small. My brother in law is a plumber so he was going to check on some prices for me. Any idea what you paid for the munchkins in the past?

What booth will you be at? I plan to get up there.

-Chris

 

[solarguy]

You'll need to do a pretty comprehensive heat loss on your home based upon the description before you can select any equipment. We'll be at booth 503.

 

[Nofossil]

Quite the plumbing diagram - makes it really easy to understand what you're planning.

There's a long-running discussion / debate on the merits of pump-per-zone vs. zone valve based systems. I haven't been able to get my head around all of the arguments pro and con, but I'd be curious to look at the differences in initial cost and electrical power requirements for a system of the complexity that you're envisioning. I'm hoping that some knowledgeable folks will chime in.

Minor detail - I think you have the wood boiler tempering valve / pump drawn incorrectly, assuming that valve is supposed to provide inlet temperature protection.

I've also undertaken an effort to try and collect a lot of the discussions about the decisions and tradeoffs involved in a project like yours. It's nowhere near done yet, but it might help a bit. Link is here. Comments, corrections, clarifications, and suggestions gratefully accepted.