Your Comments on Pellet Furnaces

[69Stingray]

Been lurking here for a while, finally trying to decide on a pellet furnaces to replace my 20+ propane forced hot air unit. I have a 2,000 sq. ft house, 2-story, one zone.

Here is what I have found so far:

Harman PF100

• Not available until next spring
• The store est. a price of approx. $5-6k installed
• Spec'd for up to 2,500 sq. ft
• Blower = 1,000 cfm
• 0-112,000 BTU

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HS Tarm Multi-Fuel Broiler

• NH business (I like that).
• 91% eff. rating. What do these ratings mean and are they all apples-to-apples?
• Technical Brief states it can be used for forced-hot air, sounds like a complicated install. Also states can be used for domestic hot water.
• 51,200 - 146,700 BTU depending on model

Any experience with HS Tarm and using for forced hit air (with or without domestic hot water)??

(broken link removed)

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(broken link removed) Air Bulletin.pdf

St. Croix SCF-050

• Website quotes $3,350, therefore I am assuming approx. $5k installed
• 45,00 BTU/hr MAX.
• 800-1,800 sq. ft (too small I believe).

http://www.pelletking.com/Wood-Pellet-Furnace-St-Croix-SCF-050.aspx

Fahrenheit Endurance 50F

• 18,000 - 50,000 BTU/HR
• 600/800 cfm fan speeds

- No sq. ft. or eff. specifications.

(broken link removed)

Magnum 6500/7500

• 63,000 BTU/hr w/ pellets
• 1240 cfm blower
• Up to 87% eff.

(broken link removed)

Harman and St. Croix appear to be out of the picture for this year. Looking for comments on the HS Tarm, Endurance and Magnum options.

What BTU do I need for 2,000 sq. ft? How important is the blower cfm? What about eff. ratings?

Thanks, Zach Tripp
Southern NH

 

[ssupercoolss]

i can be wrong, but i think pellet boilers may really suck down the pellets. so much that it may only be a little cheaper to run. talk to as many people as you can that have them. ask them how many bags they are burning per day, how many sq feet...etc. a bag of pellets is now up around 4.50 a bag.

 

[69Stingray]

Thanks futureboiler, that is the info I am looking for here. I hope people with some experience can chime in.

 

[Titus]

Wow, hard to compare since they are such different appliances. I mean, you've listed both hot air furnaces and boilers, along with whole-house units and supplemental units. $3000 to $10,000 price level units.

My advice.... start from the beginning. Decide about whether you want to heat a room, or the whole house? Do you want to supplement your current system or replace it? Sticking with hot air will cost less than buying a boiler. Get a heat load analysis on your house so you know how much heat you actually need. Are you looking to spend $3000, $5000, $10000?

How much work are you willing to do... i.e. feeding fuel, cleaning, emptying ashes, etc.?

Do you leave the house unattended for days.... i.e. how long does the appliance go without tending?, do you keep old system for back-up?

Earlier comment about pellet boilers consuming pellets rapidly is true... but if the unit is heating the whole house as opposed to a stove heating a room, of course it's going to need more pellets. The comparison should be between pellets consumed and the old fuel they displace.

 

[begreen]

The pellet boiler will consume fuel no doubt, but in terms of btu input I don't think it would be much different from an oil boiler. I'm guessing about 40-80 lbs per day, depending on the climate, season and house. If oil ~2.5-5 gal / day. With oil at ~ $5/gal and pellets at ~$5/bag, the pellets seem cheaper on a btu basis. 1 gallon of oil = 139,000 btus and one bag of pellets = ~320,000 btus. So if the boilers were equally efficient, it might work out ok. A cold day might be $10 of pellets and like $25 of oil.

This is not great when compared with free or cheap wood, but perhaps a good deal in an urban environment. If I were getting a bulk rate for pellets (say equiv. to $3/bag) and bulk delivery then it might be a good alternative. But before investing in a new boiler I'd want to be sure that the supply infrastructure was in place and reliable over the long term.

 

[webbie]

"really suck the pellets" probably relates to the fact that - with any boiler or furnace, you are giving up the "space heating dividend" which comes from a heating appliance in the living area. This is true with wood stoves also...and other fuels.

That doesn't mean that pellet boilers and furnaces are not efficient.....just that heating the entire house uses more energy than a space heater.

It might be a rough guide to figure a ton of pellets against 100 gallons of oil....or 110 gallons.

I see no need to spend the big bucks on a boiler and convert it to hot air - even considering any advantages. That leaves you with fewer options. In terms of size, I think the Magnum would easily do the job as would other at 60K BTU (output) or above.

I hope you are considering adding on as opposed to complete replacement. A pellet furnace, in most cases, should not be the sole source of central heat...

 

[69Stingray]

Thanks for the replies everyone.

Sorry for not being clear enough.

The goal is to replace my current 20 year propane hot air furnace with a pellet furnace, therefore, heat the entire 2,000 sq. ft. house. The current furnace is on it's last leg so the plan is to replace the entire unit (had it serviced twice at the end of the last heating season). The pellet furnace would be the only heat source. Propane is my only heat now, what is the difference? Is the issue that pellets have to put into the furnace every so many days where as the propane tank is filled once every couple of month?

Which units are "add on" units? That is not my plan, so that unit would be eliminated. I find a lot of the literature on the website vague.

The Tram is a boiler, but it is my understanding it can be used for hot air via a heat exchanger. Is this worth it? It doesn't sound like it.

Just trying to understand my options and the pro/cons of each.

 

[stoveguy2esw]

i would not recommend a pellet fueled appliance as an only heat source , but then i wouldnt recommend any appliance other than maybe woodstove as only heat source(and you can still run outta wood). a pellet unit (like your existing furnace ) needs electricity, without it , it just takes up space , not heating it. that said , a pellet furnace may be a good deal depending on fuel costs comparison , use 8.5Kbtu times lbs X the efficiency rating to get a rough idea on output , (unless the brand has a different stated btu input rating)remember pellet brands may state they offer 8500 BTU per pound , but thats on the "input side" output is based on the efficiency of the unit. a unit that is rated at 78% (default) efficiency with pellets at 8500 BTU would translate to a best case of 6630 BTU output. many manufacturers use stated btu input ratings X the amount of Lbs/HR they feed to give a BTU rating. at best multiply that by the efficiency rating to gain a closer idea of the actual btu "output" of the unit

by the way , contact "kinsman stoves" for input on the farenheit unit , he carrys em and is a good source of info on the unit

 

[webbie]

All these unit can 'add on' to an existing system....

I also would suggest against using pellets for an only fuel....you cannot call the LP or Oil service man when your pellet unit goes on the fritz. You may have to wait days for parts or service. Also, if you have a mortgage on the house the bank wants to see a unit capable of heating the home without user input.

 

[sinnian]

Most insurance companies won't insure you if you have pellets OR wood as your sole source of heat. They must have a back up source. The insurance companies reasonings is that if the pellet/wood boiler/furnace/stove runs out of its "wood" there may be a potential risk of frozen pipes.

Any reason the Traeger/Pinnacle is not on your list?

 

[69Stingray]

Jsut missed the Traeger/Pinnacle, did I miss any other options?

I did use some online calculators, based on the gallons of propane I used last year, I determined the BTUs I needed. When I determine the tons of pellets to get to that BTU rating, it worked out to be a $1,500 annual savings @ $265/ton.

 

[jrousell]

I own and operate the Harman PF100. If you ahve any specific questions about that unit, let me know.

I ended up buying the larger blower option( it has 3 speeds to choose form which I wanted that flexibility...) but I am not all that sure thta I shuold ahve boithered, the low and medium speeds are plenty...

 

[ex-oil slave]

To adkdadto4

I own and operate the Harman PF100. If you ahve any specific questions about that unit, let me know.

I am in the final stages of installing a PF100 myself. Can you tell me the size of your main supply duct? I'm running two 8 x 14 main ducts off of my supply plenum and calculate that I can move approx. 1100 CFM @ a velocity of 700 F/M. I have the 2000 CFM
blower and plan on running it on the lowest speed. I was just wondering about your experiences and configuration.

 

[jrousell]

That is just about the same size that I have...My plenum coming off the unit has to do some twisting and turning to make it to our central set of ductwork, but it averages about the same cross sectional area as what you have ( ~225 square inches... if memory serves me correctly)

I also have the 2000CFM three speed blower, I run it most of the time on the lowest or medium setting. The highest setting is overkill for my setup. I get a nice gentle warmness from the ducts that is constant.. not a forcefull whooshing like the propane fired furnace that kicks on and off. I went for the larger multispeed clower becasue I wasn;t sure which woudl be best for my setup.. until I had it in place and tried it out... a 1250CFM blower will be perfect for most people.

that was the biggest pleasant surprise with my experience so far.. a nice constant heat that you don't even notice, versis most forced air systems...

 

[backpack09]

Jsut missed the Traeger/Pinnacle, did I miss any other options?

I did use some online calculators, based on the gallons of propane I used last year, I determined the BTUs I needed. When I determine the tons of pellets to get to that BTU rating, it worked out to be a $1,500 annual savings @ $265/ton.

Just a note, current prices for a delivered ton of pellets in MY area is closer to $350.

 

[BrownianHeatingTech]

Wide variety of price/quality in that list.

Doing a heat exchanger with a boiler is no big deal. It allows the boiler to supply both heat and hot water, and is often more efficient than a straight hot-air system.

Heat load can be estimated based upon square feet, but accurate numbers would require a heat loss analysis, based upon the measurements of the building.

The required airflow would need to be determined based upon the actual heat load.

Whereabouts in NH are you located? (and, by the way - nice choice of car!)

Joe

 

[WoodNotOil]

I like that my wood is local and stable in price. (Well mine is free, but if I bought it the price would be stable too.) Pellets are manufactured, packaged, and shipped. The price keeps going up. If you can afford it, get a gasifier boiler and plenum exchange. Keep a lookout for used boilers or go tankless like Nofossil as your backup. Just my $0.02.

 

[ex-oil slave]

To adkdadto4

Thanks for the reply... My math for flow volume and velocity indicated that using the fan on a higher setting would generate too much flow noise in the ducts and registers. I'm replacing a 27 year old oil burner and I've had to add some additional supply and return registers to get maximum (for its size) airflow thru my main duct and keep supply/return flows balanced. Hopefully I'll have it fired up by the end of this weekend and I'll post the results. I can't wait to see if all my expectations will be met.

On a different note, my main concern with this or any pellet stove has to be the reliability of the mechanics, specifically the pellet auger delivery system. Have you had any issues with feeding? Do you do anything special to insure reliability in this area? Do you get a lot of fines? How has the electronics performed? Does it shut down and restart reliably? Are you using the factory thermostat and does it perform adequately? What do you have the feed rate set at? Are you using outside air? How long have you been using your furnace?

Thanking you for your replies in advance. I hope we can share our experiences in the future.