New to researching pellet boilers

[justinraz]

Hi All,

So we bought a house last year, and wanted to see what oil was going to be like. It killed us. Over $3000 and that is keeping the house at 62 degrees. I know this winter was bad, but I need to look into alternatives. I have researched a million sites and things over the past year. Just looking for others opinions.

Quick run down on the house. 1988 sq ft. Semi finished basement, finished attic (3rd bedroom is used). Radiators with baseboard. About 50% of the windows are updated, looking into doing the rest. No duct work. The outside is stucco, with some hairline cracks. I will tackle that this summer. A few wall unit air conditioners. Also this will be our last house, so we won't have an issue with wanting to put a little into it.

We do have natural gas on the street fairly, and cheap to run to the house. With the idea that oil is always going up, gas could go up, try to keep off of fossil fuels statements made, I would rather focus on something else.

I was looking into Pellergy since they are made in Lancaster, PA where I live, but no distributors. I probably would go with a Harman PB105, unless someone else has better recommendations. I also plan on adding some mini splits to help with cooling/heating.

Am I overthinking, high as a kite or does this seem practical?

 

[stee6043]

If you're looking simply to drive the lowest total cost look no further than natural gas. Pellets have just as much probability of going up in cost as gas (in my opinion only) in the future. Cord wood you collect from your own property is about the only thing you can count on not increasing in cost in the future.

 

[__dan]

Natural gas is by far the easiest and cheapest solution. Look into a condensing boiler like the Weil McLain Ultra with a separate indirect tank for DHW. With the fracking process, they are predicting nat gas reserves in the US of over 200 years. Bottled gas is what is expensive and volatile in price.

 

[moey]

If your looking into a pellet boiler and multiple mini splits your probably approaching the cost of a geothermal system may be worth getting a estimate. If it were me Id hook up to that NG line.

 

[justinraz]

Thank you all for taking the time to read my thread. I will probably go the gas route.

These opinions all match up with the contractors, and what my cousin thinks. He has been in the HVAC business for 17 years, so we would be doing the work ourselves (except hooking up the gas to the house). He is not a big geo-thermal person, and also suggested getting natural gas. Most of the people that I had at the house to consult about geo-thermal pushed for the natural gas too.

 

[flyingcow]

FWIW, I had two air sourced HP's installed up here in the north land, and i like them. They are the newer improved/efficient units. So far so good. heat well, and i like the performance on the A/C side. For me a much better choice than a the old style window units.

 

[Boil&Toil]

Natural gas and insulate/seal the heck out of it. 1988 is not a magical sign that it was well-insulated - nor is 2014 - people that build houses they don't intend to live in themselves almost always cut corners on the insulation. If it's "your last house" then you'll save from now until the end of house (or you) by doing everything you (reasonably) can to make sure it's as well-insulated as possible.

And being off the NG grid and never likely to get on it - flyingcow - how low does it go that those work effectively? I've done the math here and so long as the things work effectively at a COP of 3.3 or better, they are cheaper than any other source of heat I have available - but there will be a part of the year they are useless, unless the technology has seriously changed. Which leads to the geothermal direction, but those cost SO much more than the air versions it does not make sense (even before you dig a trench or drill a well.) Actually I have thought about putting the outside part of a mini-split in a tunnel fed by earth tubes or something crazy like that, but it would take a good bit of soil cover to get enough heat through the winter (still, I own a [not-very-good] backhoe, so it's barely possible...)

 

[flyingcow]

well below zero. At 15 below they shut off.and I can only go by what they give me for figures. I've not measured myself. but like 17 degrees Fahrenheit outside temperature the unit use 2600 watts. we used it quite a bit for the month of February. In it cost us an extra $55 compared to last year's usage. this was an eighteen thousand BTU unit.when I get home I'll follow this road a little closer I'm trying to do this from my phone with voice to text. God knows what you're reading

 

[justinraz]

Well the house was built in 1911. The square footage is 1988. The outside is stucco. Most of the inside of the house has panel board on top of the walls, and drop ceilings to about 9 ft. The rooms that have updated windows hold heat well, so obviously we are going to update the rest first. So hopefully when the rest of the windows are updated, whatever heat source we decide will hold heat well.

Flyingcow: When you say air sourced heat pumps, this means mini split? We own a townhouse that uses a heat pump (forced air), so just checking the verbiage. I saw this article when researching, http://www.inforrm.com/air-source-heat-pumps/. Seems to be more for under the floor heating systems than my radiators/baseboard. Also during the search, the mini splits popped up. I have been looking at the Mitsubishi Hyper heat, suppose to be 100% efficiency between 0-5f degree.

 

[Boil&Toil]

100% efficient is terrible on a heat pump; means you might as well shut it down and turn on resistive heat (or better, light the boiler.) 300% is more like it, though they like to mix Wh & BTUs to keep the numbers confusing. Actually they are claiming it can manage 100% of rated output at 5F, and it's at about 1.89 COP but "not counting defrost cycle" is a small note that may impact actual cold-weather efficiency in a big way.

COP - coefficient of performance - Heat into the house in watts/power in in watts. Should be a good deal more than 1 (100% efficient)

HSPF - heating - heat into the house in BTU/power in in watt-hours (over a heating season - makes a bigger number, and buried in there somewhere is the "average season somewhere" it's based on, which is probably not yours.)

Seasonal COP = 0.293 HSPF. But you still have the mythical season (ie, outdoor temperature profile, and heating COP gets worse the colder it is.)

EER - cooling - Heat out of the house in BTU/power in in watt-hours (95F exterior - ya know, the days you might actually turn on the A/C up Nawth.)

SEER - cooling - Heat out of the house in BTU/power in in watt-hours (over a cooling season - makes a bigger number, and buried in there somewhere is the "average season somewhere" it's based on, which is probably not yours.) SEER is better than EER since the COP (cooling) is better when it's cooler outside, if you assume the A/C is run all the time it's over 68, rather than only when it's actually hot.

So, if flyingcow's unit is putting out 18,000 BTUs/hr at 2.7 KW in at 17F, it's operating at 18/(2.7*3.413) = a COP of 1.95 @ 17F - or 195% efficient. (3413BTU=1kWh)

On my spreadsheet, with prices as I last looked them up, that makes it more expensive than pellets, but less than oil. Thing is, when it's 25 or 33 out, the COP will improve, and the cost to operate will go down. But - it also means that when you need the most heat (because it's coldest) the air-source heat pump costs the most to operate (and eventually will slip down to "100%" or, "don't bother" - so we need the woodburners.) Even a COP of 2.9 is currently better than pellets, and that can be had on the seasonal basis (HPSF=10 or better), at least, but I doubt the seasonal figure is for a Northeast US climate...I just haven't dug deep enough to find out where it is from. You also need to check the mini-splits carefully - the bigger ones rarely have as good EER/SEER/HSPF as the little ones do.

 

[flyingcow]

I have been looking at the Mitsubishi Hyper heat, suppose to be 100% efficiency between 0-5f degree.
Thats what i have.



Boil and Toil---way over my head what you posted. BUT the 18k unit makes the wife happy, seems to me a close performer( my back of the envelope figuring, which usually is horribly flawed) until you drop below zero f.


The reason I posted about my Mitsu Hyper unit wasn't for his heat, but for A/C. He has access to NG.

 

[flyingcow]

And i do not have mini splits. One 18k and one 12k

 

[Boil&Toil]

?(I'm confused, not trying to argue)?If you have a compressor unit outside and an air unit inside, AFAIK that's a mini-split - need not be one compressor and multiple indoor units - the "split" AFAIK, is separating the compressor and outside coils from the indoor unit, which the HyperHeat seems to be, from the documents I'm finding. As you said "not a window unit" and as you didn't say, not a whole-house unit. Perhaps you have some other variant, or you have a different idea about what is called a mini-split?? I'm guessing you have two outside units (12&18K) and two inside units (12&18K) - in which case I'd say you have two separate mini-splits (and that is the way they seem to end up most efficient, rather than one compressor and more indoor units.) I run down the numbers just because it helps me to think through decisions...and keep the back of my envelopes honest.

And yes, he just fires up the gas boiler/furnace, and the crossover temperature (where gas costs less than heat pump in heating mode) will probably be a lot higher. Up around 47F the HyperHeats run near 3.4 COP, so 8.6 KWh= 1 Therm (for example) and at Vermont prices that is actually a bit cheaper than gas (not that I can get gas where I am in Vermont.) And I do heat the house when it's 47, where I don't usually air-condition if it's 74.

 

[justinraz]

Boil&Toil: Thanks for the breakdown. That will help me get my head wrapped around some of the info I have been reading.

I had one guy stop by about geo and turned it into adding 7 Mitsubishi hyper units to heat/cool the whole house. His quote was over 30gs.

As far as I knew the mini split options were basic (15f degrees) with wall, cassette, suspended (which I wanted), or floor mount. Then the hyper heat (5f degrees down to -13 degrees) which was intriguing but is a one to one system. I am not to thrilled with the idea of 7 units hanging around the outside of the house.

Should I even venture to bring up the velocity systems? Through the wall air conditioner/heater (since I already have 3 working ac units/2 dead units)?

 

[Boil&Toil]

One reason to really work on the insulation/sealing/windows (before buying new heating/cooling equipment) is that it can reduce the amount of heating/cooling capacity you need to buy. As for 7 outside units, in most cases the line lengths you can run are such that you could group them all in an inconspicuous (or shubbery-concealed) location, rather than circling the house with them. And I'd shop around a bit more, since that seems high on a per-unit basis. But the essential thing here is that natural gas wins for heat most of the time you need heat, so you can even look at the "cooling only" mini-splits. If you cannot convert your oil boiler to a gas burner, your original concern about gas possibly going up can be addressed by getting a gas boiler that could take a pellet burner if that happened. Without taking time for an exhaustive search (it's bedtime...) I'm not getting useful results on "velocity heat pump" - what I find for "through-wall heat pump" does not (on a quick look) seem too impressive for efficiency numbers, though I've only looked at a few. Comparing to a window-type air conditioner, the mini-splits are a LOT quieter, for one thing.

 

[heaterman]

Insulate and connect to that natural gas line.
I don't know what NG cost is per therm (100,000btu) in your area but here in Michigan, where we are headed well below 0 tonight AGAIN we currently pay about $.85/therm including all the add ons for delivery, nuclear decommissioning yada yada yada..
If the local cost of natural gas is around $1.50 or higher and you can get pellets in the $200/ton range........then I would think long and hard about a good pellet boiler. But get a good one that doesn't require any babysitting.

That being said, I found much to my surprise that the Windhager pellet boiler I installed last winter dropped my annual fuel cost about 25% below what I averaged per season for natural gas.
This is comparing the brutal winter we have had this year (pellets) to the average of the 3 previous years (gas).
I have to confess that when I crunched numbers initially, it looked like the cost of operation would be very close between pellets and Natural gas for me.
To my surprise and delight the Windhager burning pellets provided the needed heat for less cost than the Viessmann burning natural gas.

I have to say that this will probably not be the case with all pellet boilers. The Windhager has the ability to modulate from about 25,000 btu up to about 90,000. Many of the makes on the market can not do that and lose efficiency due to much higher on/off cycles.

Would it pay me in outright $$ to go with pellets over natural gas? Not for a very long time but I had a number of reasons for installing it other than just energy cost savings.

 

[justinraz]

Well I talked to the gas company. It will cost $439 to run a line to the house. That is way cheaper than the original quote of $1100 I got May 2013. The average cost to do this is $3030, and that will be the price I would have to pay if I do not hook up within a year.

UGI's price per therm until March 2014 is .62 cents. I am not sure if it is like our electricity to where we can pick and choose. I'll look into that later.

My cousin is going to get me prices on some gas boilers.

I guess I should bounce this thread over to the It's a Gas! forum.

 

[heaterman]

Re: gas boilers....
My favorites are Viessmann, Triangle Tube, Lochinvar. In that order. The HUGE thing with any high efficiency gas boiler is getting it installed/piped up correctly. They are most definitely not the same as a regular old cast iron boiler and many of the installers still try to pipe them up that way. Especially older guys who just do it the way they always did and never read the I/O manuals.
We do sawzall surgery on more than a few every year that are installed wrong and there is nothign to do but cut it out and start over.

I am not a fan of the aluminum block/heat exchanger models made by Buderus, Weil McClain, Utica and others. Seriously. Aluminum? And water? Think about it.
Better yet, put some water in an aluminum pan for a month and just leave it sit. Tell me what you see going on after 30 days.

 

[justinraz]

[/quote]I am not a fan of the aluminum block/heat exchanger models made by Buderus, Weil McClain, Utica and others. Seriously. Aluminum? And water? Think about it.
Better yet, put some water in an aluminum pan for a month and just leave it sit. Tell me what you see going on after 30 days.[/quote]

My cousin shot that one down already.

 

[BoilerMan]

I'll second Heaterman's mod/con recommendations in that order..............

TS

 

[__dan]

Re: gas boilers....
My favorites are Viessmann, Triangle Tube, Lochinvar. In that order. The HUGE thing with any high efficiency gas boiler is getting it installed/piped up correctly. They are most definitely not the same as a regular old cast iron boiler and many of the installers still try to pipe them up that way. Especially older guys who just do it the way they always did and never read the I/O manuals.
We do sawzall surgery on more than a few every year that are installed wrong and there is nothign to do but cut it out and start over.

I am not a fan of the aluminum block/heat exchanger models made by Buderus, Weil McClain, Utica and others. Seriously. Aluminum? And water? Think about it.
Better yet, put some water in an aluminum pan for a month and just leave it sit. Tell me what you see going on after 30 days.

Hi HM. Certainly not disagreeing with you or your experience. I put the WM Ultra in for my brother more than ten years ago. At the time it was their second year of production (one of their early models) and IIRC the only condensing boiler on the market at the time. Only trouble was a bad outdoor air thermistor at startup and a split condensate tubing at the accessory pump outlet, maybe a bad circ. I'm sure he does not clean it. It's been perfectly reliable, quiet, and efficient.

I had confidence in WM knowing what they're doing as, I believe, the largest boiler producer in the US. I googled for problems with the aluminum heat exchanger and could not find any, just some unrelated homeowner complaints but not any alum block related.

They make rowboats, roof shingles, sheds, out of aluminum and I've never really heard of any serious corrosion issues. Aluminum wire is not rated for earth contact and I've seen that corrode / oxidize, usually with heat as it works loose and causes resistance heating / burning at the connection. The wire can be cleaned and reterminated.

I usually recommend the WM Ultra as something I'm familiar with and would certainly like to know if I'm making a mistake with that. Seen a lot of trouble with boilers not rated for condensate. My guess would be that WM uses some type of alum alloy that has been extensively torture tested. I tend to have faith in and depend on the factory engineering.

 

[Former Farmer]

It will cost $439 to run a line to the house.

Run the gas line to the house for that price! Even if you don't use it for heating, you can always use it for a gas clothes dryer or a gas stove. Gas dryers are much cheaper to run than electric ones. And when you do sell the house, it will be a good selling point versus not having natural gas.

 

[heaterman]

Hi HM. Certainly not disagreeing with you or your experience. I put the WM Ultra in for my brother more than ten years ago. At the time it was their second year of production (one of their early models) and IIRC the only condensing boiler on the market at the time. Only trouble was a bad outdoor air thermistor at startup and a split condensate tubing at the accessory pump outlet, maybe a bad circ. I'm sure he does not clean it. It's been perfectly reliable, quiet, and efficient.

I had confidence in WM knowing what they're doing as, I believe, the largest boiler producer in the US. I googled for problems with the aluminum heat exchanger and could not find any, just some unrelated homeowner complaints but not any alum block related.

They make rowboats, roof shingles, sheds, out of aluminum and I've never really heard of any serious corrosion issues. Aluminum wire is not rated for earth contact and I've seen that corrode / oxidize, usually with heat as it works loose and causes resistance heating / burning at the connection. The wire can be cleaned and reterminated.

I usually recommend the WM Ultra as something I'm familiar with and would certainly like to know if I'm making a mistake with that. Seen a lot of trouble with boilers not rated for condensate. My guess would be that WM uses some type of alum alloy that has been extensively torture tested. I tend to have faith in and depend on the factory engineering.

Let's just say the W/M people have told me directly that boiler has a pretty specific "design life". The corrosion is on the fire side of the combustion process when there is condensation present.
A lot of people who installed them on a high temp system like an existing baseboard design are indeed doing just fine with them. That's because the boiler never gets down to condensing temps (<140* water temp) The boiler is typically on at 160 or higher so there is no condensation happening in the HX (and no 90%+ efficiency).
Lash any of the aluminum block boilers up to a true low temp system where you are running 90%+ and the condensate is pouring out of the thing and the life expectancy drops substantially. High temp traditional systems they'll usually do pretty well with.
W/M does have specific recommendations out for the type of fluid used on the water side and also a service bulletin stating you have to use their additive if you expect to have any warranty on the HX.