Pellet boiler in conjunction

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ontario star

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Feb 27, 2014
1
oswego, ny
Hello,
I have a 2,500 sq ranch with a finished basement. I have a propane boiler system that works at 80%. I was thinking of getting a pellet insert to put in the fireplace on the first floor however, after some research I am thinking of getting a pellet boiler to use for the whole house. My question is.... ( I am a new homeowner and pretty ignorant about a lot!!) do they make the pellet boilers to work in conjunction with my propane boiler so that I can leave for the weekend or a week without having to worry about feeding pellets? Thanks....
 
You have tons of options. You can simply have enough pellets to make it through the weekend, or some simple automation can trigger your fossil fuel boiler to come on for you.

I took the dry contacts off my zone controller and go to an aquastat on my Kedel with a timer set for 10 minutes. If there is a call for heat, the timer will wait 10 minutes the close the circuit to go to the aquastat. If the aquastat is above 140*f ( to indicate the pellet boiler started. And is heating up) no signal will tell your propane to start. If the temp is below 140*f ( or whatever you set the aquastat to) the dry contact closure will complete the circuit to T-T on your boiler to start it up. Very simple.
 
I chose to plumb my boiler in series (as apposed to parallel) My system (oil boiler/ pellet boiler) work together. My intellidyne HW 3250 (very recommended) has tracked my oil burner use this year to just running 20.1 hours helping my pellet boiler (I heat 2 buildings...11 zones all with DEEP setback thermostats) Now a lot of people here say "by running with series , I 'm wasting heat by heating my oil boiler" I say " since I have NO heat going up my oil flue(verified...because of my "field controls ...oil vent damper") ANY heat "lost" from my oil burner is NOT lost because it remains in my dwelling.
Also, I have personally left my system "un attended for 2 weeks (I did so just to see if it would work...I was here but chose not to service) This was possible because of a 1500 lb bulk hopper. If I was going away for an extended period, I would set up my pellet boiler and let it roll. I suspect it would burn everything in its hoppers...shut down...and handoff to my oil boiler. At this point my pellet boiler would be heated by my oil boiler(again NO lost heat because it is in my dwelling.

DLZ uses a time delay..."If there is a call for heat, the timer will wait 10 minutes the close the circuit to go to the aquastat." A great idea....My intellidyne uses ::DT T as a trigger to release the oil burner to fire. An added benefit to "my" way is the intellidyne will continue to work saving me money by maximizing efficiency by regulating JUST the oil burner
Good luck in your choice. An added benefit to integrating a pellet boiler is ...NO cold "nooks and crannies"...mess down stairs...Down side...your gonna burn more pellets
 
Hello,
I have a 2,500 sq ranch with a finished basement. I have a propane boiler system that works at 80%. I was thinking of getting a pellet insert to put in the fireplace on the first floor however, after some research I am thinking of getting a pellet boiler to use for the whole house. My question is.... ( I am a new homeowner and pretty ignorant about a lot!!) do they make the pellet boilers to work in conjunction with my propane boiler so that I can leave for the weekend or a week without having to worry about feeding pellets? Thanks....


I had a pellet boiler put in last fall and had it plumbed in so that I can manually go between it and the oil boiler that is still there. All I have to do is flip a few sitches and ball valves and I can switch back and forth between the oil boiler and the pellet boiler. My plumber told me that he could have also plumbed it in so that this switch would be automatic but I chose to make it a manual switch instead.

My house is roughly the same size as you's and I've been using the Windhager Biowin boiler to heat it. Unlike a pellet insert or stove, which I too considered at one point, the boiler ties into the existing heating elements that are run throught the home. It provides a much more uniform, comfortable heat throughout the home. the boiler also has a larger hopper and requires less cleaning and maintenance.

Have you started researching the pellet boilers yet? Some of the players are Frohling, Harmann, Kedel, Harmann, Okofen & Windhager. I can speak for anything other than the Windhager Biowin which I own and am happy with.

Best of luck.
 
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I had a pellet boiler put in last fall and had it plumbed in so that I can manually go between it and the oil boiler that is still there. All I have to do is flip a few sitches and ball valves and I can switch back and forth between the oil boiler and the pellet boiler. My plumber told me that he could have also plumbed it in so that this switch would be automatic but I chose to make it a manual switch instead.
If you are at work on a very cold day...what happens if your pellet boiler shuts down as you leave...(what ever scenario you choose) will you come home to a disaster? My point is ...Will your setup protect its self?? For me ...I can in less then a minute (New York minute) flip 3 ball valves and nothing else (being as its series all controls are shared) and I'm completely off my pellet boiler. More importantly, my set-up will "seamlessly switch to oil in the event of a pellet boiler problem at absolutely no cost to its efficiency.
 
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Mine is similar but connected in parallel with my oil boiler. I could just set the thermostat on the oil boiler lower and it would automatically start if the pellet boiler isn't keeping the water hot enough. But I don't want to burn oil so I leave its switch off. I also have ball valves to the pellet boiler lines but I don't bother closing them. When I go on vacation, I just turn the oil boiler on and turn the pellet boiler off. With the switch to the pellet boiler off, its circulator doesn't run.

Mine is a PB105. I know some of the Kedel installations are removing the oil boiler completely. My uncle for example. In his case it was a space issue - didn't have room for both.
 
Mine is similar but connected in parallel with my oil boiler. I could just set the thermostat on the oil boiler lower and it would automatically start if the pellet boiler isn't keeping the water hot enough. But I don't want to burn oil so I leave its switch off. I also have ball valves to the pellet boiler lines but I don't bother closing them. When I go on vacation, I just turn the oil boiler on and turn the pellet boiler off. With the switch to the pellet boiler off, its circulator doesn't run.

Mine is a PB105. I know some of the Kedel installations are removing the oil boiler completely. My uncle for example. In his case it was a space issue - didn't have room for both.



If you are at work on a very cold day...what happens if your pellet boiler shuts down as you leave...(what ever scenario you choose) will you come home to a disaster? My point is ...Will your setup protect its self?? For me ...I can in less then a minute (New York minute) flip 3 ball valves and nothing else (being as its series all controls are shared) and I'm completely off my pellet boiler. More importantly, my set-up will "seamlessly switch to oil in the event of a pellet boiler problem at absolutely no cost to its efficiency.


The greatest length of time that we are away from home is about eight hours and even that's only twice a week. Other than that someone is always home. As I said it's completely manual switch between the boilers. The pellet boiler distributor recommended doing it this way and I chose to do it this way. If for some reason the pellet boiler shut down during the day and no one was home there would be no heat but I wouldn't expect a disaster. I had my basement rim joists spray foamed to R21 this year and I'm going to insulate the walls in the basement down to the frostlne in the next year or so as well. I'll also be revamping the attic to make the heat loss as little as possible and maintain heat throughout the home so I wouldn't expect frozen or burst pipes if the home sat with no heat for five to six hours.

I'm confused by your post though. You say you have to switch three ball valves to switch off your pellet boiler and over to oil. Yet you also say that the pellet boiler will seamlessly switch to oil in the event of an emergency with the pellet boiler? So if your's capable of manual and automatic switching? I'm not a plumber and don't understand all of the plumbing concepts but it seems as if having to switch three ball valves would not allow a system to switch itself automatically as needed in the event of an emrgency.
 
Mine is similar but connected in parallel with my oil boiler. I could just set the thermostat on the oil boiler lower and it would automatically start if the pellet boiler isn't keeping the water hot enough. But I don't want to burn oil so I leave its switch off. I also have ball valves to the pellet boiler lines but I don't bother closing them. When I go on vacation, I just turn the oil boiler on and turn the pellet boiler off. With the switch to the pellet boiler off, its circulator doesn't run.
Potential problems....first off your pellet boiler will continue to chug along at a lower temperature(because of your oil boiler T stat. set point) for longer because of that...circulators will see un necessary wear because they run longer.. second ...running parallel requires an additional pump
 
Let me start by saying ...I have built over 50 new homes and have lived in 4 homes myself (one new one ...3 old ones) I know houses inside and out.(and I'm still learning) My current house I re-roofed it with slate and copper...copper snow slides. This because my last house required me to "roof rake " after every snow storm. This impart because of "sky lights" and because of the ability of snow to grab onto asphalt shingles . When on vacation I would have to make arrangements. What did I learn....sky lights over a heated space in the north east...bad idea.


The greatest length of time that we are away from home is about eight hours and even that's only twice a week. Other than that someone is always home. As I said it's completely manual switch between the boilers.
I live a lot like you....except my house is not as tight as you describe yours. But leaving all heating responsibility to a pellet device is beyond MY comfort level....

I'm confused by your post though. You say you have to switch three ball valves to switch off your pellet boiler and over to oil. Yet you also say that the pellet boiler will seamlessly switch to oil in the event of an emergency with the pellet boiler? So if your's capable of manual and automatic switching? I'm not a plumber and don't understand all of the plumbing concepts but it seems as if having to switch three ball valves would not allow a system to switch itself automatically as needed in the event of an emrgency
My ball valves were installed for no other reason but for serviceability only. Every ...and I mean EVERY part of my system can be isolated. Two years ago one of my circulator pumps crapped out. Flipped two ball valves and didn't have to drain boiler. my house continued to heat its self while I changed the circulator. even my expansion tanks can be replaced without sutting down. Make no mistake about it, my primary heating system is OIL... It rarely comes on because my pellet boiler keeps everything hot. All my controls are for my oil boiler. All my zone circulators (six for primary house and a seventh pump( ::DT T pump. )servicing 5 zone valves in second house. are used by both boilers because its plumbed "series"
 
Let me start by saying ...I have built over 50 new homes and have lived in 4 homes myself (one new one ...3 old ones) I know houses inside and out.(and I'm still learning) My current house I re-roofed it with slate and copper...copper snow slides. This because my last house required me to "roof rake " after every snow storm. This impart because of "sky lights" and because of the ability of snow to grab onto asphalt shingles . When on vacation I would have to make arrangements. What did I learn....sky lights over a heated space in the north east...bad idea.


I live a lot like you....except my house is not as tight as you describe yours. But leaving all heating responsibility to a pellet device is beyond MY comfort level....


My ball valves were installed for no other reason but for serviceability only. Every ...and I mean EVERY part of my system can be isolated. Two years ago one of my circulator pumps crapped out. Flipped two ball valves and didn't have to drain boiler. my house continued to heat its self while I changed the circulator. even my expansion tanks can be replaced without sutting down. Make no mistake about it, my primary heating system is OIL... It rarely comes on because my pellet boiler keeps everything hot. All my controls are for my oil boiler. All my zone circulators (six for primary house and a seventh pump( ::DT T pump. )servicing 5 zone valves in second house. are used by both boilers because its plumbed "series"


Not all pellet heating appliances are of the same quality or capability. There are certain pellet heating devices that would actually be beyond my comfort level to have as the sole heating source. My boiler is not one of these devices. I did a lot of research before deciding on the Biowin. The build quality, in my opinion, is far superior than a lot of other pellet heating products on the market.

This winter, due to how consistently cold it's been, has been a very good test of a heating appliances reliability and ability to perform. Other than a minor issue of Home Depot pellets causing a hard residue buildup in the burnpot, my Biowin has performed flawlessly and will save me roughly 40-50% on oil this year. (This year being especially cold I don't expect to save this much every year, ie the colder it is the more you will have to spend on any fuel source but the greater the pellets vs oil savings also). So after one very brutal winter and about 5.5 tons burned I feel very confident in leaving the task of heating my home up to my Biowin. I would never say this about any stove or a number of other pellet boilers that I've researched.

I know that the heating appliance is just one part of a larger equation though. there's the house's envelope and the distribution system as well. As far as I can see there's nothing really that I can do to improve the distribution system. I clean the baseboard twice a years to remove any dust buildup. I've bene working on getting the envelope as tight as possible to minimize the heat loss. the reason I opted to start with the basmeent instead of the attic is that the spray foaming of the rim joists was much cheaper and easier than the renovations I will have to do in the attic. I currently have R30 fiberglass batts which are most likely not truly giving me R30 performance. I'm either going to replace those or spray over them with cellulose. I need to repalce the roof baffles before I can even begin this so the attic is going to be more costly and time consuming than I could afford this heating season. For the $800 I spent on spray foaming the basement rim joists I think it was avery wise decision to do it this year and wait on the attic.

My level of understanding of the mechanical/plumbing/appliance aspects of heating a home pales in comparison to many of the posters on this website but i think that we all understand is that you can have the latest and greatest, most expensive heating appliances and equipment but if you have not properly air sealed and insulated your home then you're just throwing your money away.
 
My pellet boiler is connected in parallel with the oil boiler using a circulator to circulate the water between both boilers, a aquastat located in the oil boiler controls the on-off of this circulator. I do have ball valves installed so I can isolate either boiler if I choose. In the past 6 years the only time the oil boiler runs is in the fall when I fire it to make sure it will run if needed. The only advice that I can give you, make sure ball vaves are installed so either boiler can be shut down without affecting operation of the other.
 
My level of understanding of the mechanical/plumbing/appliance aspects of heating a home pales in comparison to many of the posters on this website but i think that we all understand is that you can have the latest and greatest, most expensive heating appliances and equipment but if you have not properly air sealed and insulated your home then you're just throwing your money away.

For me ANY thing spent in the actual heating of your house in "throwing money away" All we get is a temp "warm feeling" Now as for equipment, there is a payback by capital improvement.. Oh one of my "investments" powder coated "cast iron" radiators....."aye....that's the rub"
 
The only advice that I can give you, make sure ball vaves are installed so either boiler can be shut down without affecting operation of the other
That is only possible with a parallel hook up. with a series connection only the "add on boiler can be isolated while running... series plumbing relies on primary boiler handling controls... It could be done (plumbed so both could be isolated, but with a series connection it wouldn't be cost effective and would be needlessly complicated...
 
I had my basement rim joists spray foamed to R21 this year

Do you have an OAK with your Biowin? I ask because I had my joists foamed prior to my pellet boiler purchase, but in order to get enough combustion air, I have to leave the door leading to the bulkhead doors open a crack, and even went further by adding a vent (with flapper) on one side of the bulkhead.
 
Do you have an OAK with your Biowin? I ask because I had my joists foamed prior to my pellet boiler purchase, but in order to get enough combustion air, I have to leave the door leading to the bulkhead doors open a crack, and even went further by adding a vent (with flapper) on one side of the bulkhead.
So your not using an OAK because your rim joists are foamed? why not remove it and re-foam it with a can to "touch it up"
 
Do you have an OAK with your Biowin? I ask because I had my joists foamed prior to my pellet boiler purchase, but in order to get enough combustion air, I have to leave the door leading to the bulkhead doors open a crack, and even went further by adding a vent (with flapper) on one side of the bulkhead.

I don't have one and I'm assuming I'm getting enough combustion air as the boiler has been running without issue.

What kind of symptoms would a boiler exhibit if it there an inadequate supply of comubustion air?
 
For all of you who put in Biowins, Kedels and Harmans, what was your payback period? Or did you calculate your break-even by the number of tons of pellets you burned, and if so, how many tons did you have to burn to break-even?

Also, I'm assuming all of you who piped in your pellet boilers/furnaces in serial and parallel had an extra flue to use?
 
For all of you who put in Biowins, Kedels and Harmans, what was your payback period? Or did you calculate your break-even by the number of tons of pellets you burned, and if so, how many tons did you have to burn to break-even?

Also, I'm assuming all of you who piped in your pellet boilers/furnaces in serial and parallel had an extra flue to use?


I have a Biowin that was installed in September. I had a triple flue chimney with one unused flue. The flue was unlined so I had to have a SS liner dropped down and my stack is roughly 40 feet so it wasn't cheap. I had a plumber do the boiler install. This year I'm probably going to save 40 - 50% over oil but I don't expect the savings will be that much every year. If I had to guess I'd say the payback period will be about seven years or so. My situation is that we have two young children we plan to raise in our current home and a ridiculously low mortgage rate so barring life throwing a major league curve ball we plan on staying in the home for at least another 15 - 20 years. Hopefully this country will not totally collapse before then so I cant start seeing pure savings on my investment.;)
 
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For all of you who put in Biowins, Kedels and Harmans, what was your payback period? Or did you calculate your break-even by the number of tons of pellets you burned, and if so, how many tons did you have to burn to break-even?
For me , I didn't spend a lot of time figuring "payback" I looked quickly... and like Dana B, I figured bout 7 years. For me , saving is saving as a rule. If I know I'm saving, I just save and don't look so much at how long before payback....and besides that figure is also affected by capital improvement....example...last week I had all the windows replaced on my other heated building...In my opinion my property value was raised by just installing them. any savings on heat costs are "ice" zing on the cake!!!...and I like cake!!! "let them eat cake"
 
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For me , I didn't spend a lot of time figuring "payback" I looked quickly... and like Dana B, I figured bout 7 years. For me , saving is saving as a rule. If I know I'm saving, I just save and don't look so much at how long before payback....and besides that figure is also affected by capital improvement....example...last week I had all the windows replaced on my other heated building...In my opinion my property value was raised by just installing them. any savings on heat costs are "ice" zing on the cake!!!...and I like cake!!! "let them eat cake"


I think that within the real estate industry there are some generally accepted notions about which type of improvements actually increase the market/resale value of a residential property and by how much. I'm not exactly sure if a pellet boiler, especially a manually fed one, would increase the value much. I don't think it would hurt but I never looked at from this point of view. For me it was more about minimizing my energy costs in my primary residence over the next two decades. I think it's most likely that even if the price of wood pellets increases it will be far outpaced by the increase in the cost of heating oil.
 
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I have mine setup in series.

I set the pellet boiler temperature higher (minimum of 140 to 165 max) than the propain boiler (120). That way the propain will kick in if the pellet is not running or unable to keep up.
 
I think that within the real estate industry there are some generally accepted notions about which type of improvements actually increase the market/resale value of a residential property and by how much.
You're right...to a point...anytime you can remove a negative....its very close to adding a positive. Pellet boiler....I'll take it out if a buyer doesn't want it ....windows....taking away a negative ...
 
Okay, I figure if I switched over to a pellet boiler, I could burn between 7 and 8 tons to replace my oil use. Based upon oil prices and bulk pellet prices, I figure that would save me around $1500. Seeing as everyone has different pellet needs, some burn more and some less, how long would I need to break-even if burning 7 to 8 tons saves me $1500?
 
Okay, I figure if I switched over to a pellet boiler, I could burn between 7 and 8 tons to replace my oil use. Based upon oil prices and bulk pellet prices, I figure that would save me around $1500. Seeing as everyone has different pellet needs, some burn more and some less, how long would I need to break-even if burning 7 to 8 tons saves me $1500?


I think there are far too many variables that are unique to each person's situation to give an accurate number:

1. how much is the boiler going to cost?
2. Professional install? How much will it cost?
3. Do you need a liner dopped down? What will it cost?
4. What are the cost of pellets in your area? Will the remain stable over the next 5 years?
5. How well insulated and air sealed is your home? Are there any cheap/cost effective improvements you can make to your home that will shorten the payback period on a pellet boiler?
6. Will next winter be as cold as this winter? The colder and harsher the winter the more you will spend on whatever type of fuel you use so even if switching to pellets you will be saving more as you spend more on pellets.
7. Will you be using the pellet boiler for DHW? If not could you possibly use it for DHW for DHW to save more?


I think a safe bet is to say that you're looking at a minimum payback period of five years for a best case scenario. More likely a few years more than that though.

By the way what figure did you use for oil = pellets when determining how many tons you'd need?
 
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