Oil backup. Who needs it?

[Highroad281]

Hi All, I'd like to hear some thoughts on this from folks who are actually living it

I'm planning a gasser install with ~1000G storage in basement, and I'm really leaning towards removing the oil unit completely and committing to wood. Since buying the place 4 yrs ago we've heated the house exclusively with a Jotul Firelight and 5 cord, but we still burn a tank of oil per year to make DHW. I'm thinking the Tarm and storage is going to be a massive improvement in comfort and convenience over what I have been doing, and burning one fire a week in summer to heat DHW seems like a breeze. I'm already set up with baseboards, hydro air, and a super store so all the bases are covered.

Am I not considering something that I should be? I have heard that you can't get a mortgage on a home that doesn't have an automated central heat system... But I already have a mortgage. And I can put the oil unit back if need be.

Anything else that I'm missing? There must be some reason that most prefer parallel installs, but I'm not seeing it. Is it just the convenience, or conventional thinking, etc? Did this seem like a good idea to anyone else and they now wish had done differently?

Looking forward to your insights!

 

[peakbagger]

Vacations, unexpected family emergencies and life's unexpected surprises are the reason for a backup. A gasifier/storage system has a lot of components and in general has a lot more opportunities for failure than an oil system. I have considered getting rid of oil and installing an electric hot water heater as backup hooked to the baseboard system but havent looked into the details.

I know personally that despite having a similar setup, that I have about a 3 day window in real cold weather before I need to run the wood boiler. I dont use much oil but appreciate it when I need the backup. I have had some component issues in the winter in the past where the wood system was down for a couple of weeks. It sure wasnt planned.

I sure wouldnt want to be in a situation where a spouse was in a emergency (severe medical issue) and I had to worry about driving home to feed the wood stove.

By the way, your insurance company may object to lack of an acceptable primary heating system as the homeowners insurance is most likely based on one being there. They wont object bt if you freeze your pipes they just may not pay out.

I do have a friend with only one flue on his chimney. He uses the oil boiler controls and circulator on a primitive wood boiler system (basically a heat transfer coil on his wood stove), He has the flue pipes set up so either he or his wife can make the swap between wood and oil in about 5 minutes.. It was an electric home to begin with so he also does have some of the original electric baseboard intact. .

 

[JP11]

Since you already have an oil system....

getting rid of it will not "save" you anything. You will gain back a bit of floor space, that's it.

Not worth it IMHO. You might not see the need for it now. But it sure is a nice piece of mind. I love the fact that I set my thermostats like always. No action at all is REQUIRED to maintain that temp. I can choose to charge storage, or I can choose to do nothing and oil takes over.

JP

 

[maple1]

What do you have now for an oil boiler, and how old is your oil tank?

I got rid of my oil all together, and replaced with an electric hot water heater for DHW (when I'm not burning), and an electric boiler for backup heat (1 year old, $400 used on Kijiji). Last winter the electric boiler was only used for one day, when we were away for two - if I had 1000 gallons of storage (rather than the 660 I do have), I might have made it coasting on storage the second day too. I would not want to heat for any extended amount of time on the electric boiler, they can really make your meter spin, but the one day wasn't noticeable on the power bill. It was an easy install.

Couldn't be happier to have sent the oil man packing. It took one chimney out of the need equation, freed up a ton of space in my basement, got rid of all oil related liabilities (your insurance might be cheaper with no oil tank on your property - might want to check that out), and the electric hot water heater heats DHW way cheaper than the oil boiler with coil in it.

I think the only way I would consider keeping an oil boiler, would be if it was a newer cold start one, and I had a fairly new oil tank, and the house was frequently unoccupied during the winter - but even on the last point, I think I would lean towards a mini-split heat pump for some backup heat before an oil boiler.

I was also looking at mandatory oil tank replacement within the next two years, that was also another factor. If that is something you'd be looking at in the near future, you could likely put in an electric boiler & hot water heater for close to what an oil tank replacement would cost - and save money on lower operating costs (don't forget oil burner maintenance & service) and maybe reduced insurance rates (oil spills are pretty big dollar payouts for insurance companies). Also, with oil, you're tied to oil - with electric, you're potentially accessing multiple energy sources, like nuclear, hydro, wind, & natural gas (depending on the individual utlility, that is). If not right now, at least in the future.

My 2 cents.

 

[Highroad281]

Vacations, unexpected family emergencies and life's unexpected surprises are the reason for a backup. A gasifier/storage system has a lot of components and in general has a lot more opportunities for failure than an oil system. I have considered getting rid of oil and installing an electric hot water heater as backup hooked to the baseboard system but havent looked into the details.

I know personally that despite having a similar setup, that I have about a 3 day window in real cold weather before I need to run the wood boiler. I dont use much oil but appreciate it when I need the backup. I have had some component issues in the winter in the past where the wood system was down for a couple of weeks. It sure wasnt planned.

I sure wouldnt want to be in a situation where a spouse was in a emergency (severe medical issue) and I had to worry about driving home to feed the wood stove.

By the way, your insurance company may object to lack of an acceptable primary heating system as the homeowners insurance is most likely based on one being there. They wont object bt if you freeze your pipes they just may not pay out.

I do have a friend with only one flue on his chimney. He uses the oil boiler controls and circulator on a primitive wood boiler system (basically a heat transfer coil on his wood stove), He has the flue pipes set up so either he or his wife can make the swap between wood and oil in about 5 minutes.. It was an electric home to begin with so he also does have some of the original electric baseboard intact. .

Thanks Peak. I'm curious about your component issues. Did you pop a HX coil, a tank liner issue, or was it a controller board, etc that got cooked and kept you from running? That's supposedly one of the benefits of the Tarm, super simple. Keep a spare switch or two, a circ, and maybe a blower motor on hand if really paranoid and that's about all there is to it... But again you guys have been doing this, and I want to be convinced so I'd like to know.

My backup plan is the Jotul, just like we use now for our primary. Maybe swapping the indirect tank for one of the new hybrid water heaters would be a good idea so DHW is available in the event of component issues, but we've heated water on the wood stove before when the oil burner was on the fritz.

 

[Highroad281]

Since you already have an oil system....

getting rid of it will not "save" you anything. You will gain back a bit of floor space, that's it.

Not worth it IMHO. You might not see the need for it now. But it sure is a nice piece of mind. I love the fact that I set my thermostats like always. No action at all is REQUIRED to maintain that temp. I can choose to charge storage, or I can choose to do nothing and oil takes over.

JP

Thanks JP. Space is actually a big concern in this case, as the unfinished basement has a fairly small footprint for combined mechanicals and storage . And ideally I'm hoping to route the class A flue out where the Sideshot vent exits the house now rather than punch another hole for the through wall. I've seen mentioned on different threads people just keep a couple of plug in radiators set on low in the event of an emergency to keep the pipes from freezing, and that seems like cheap peace of mind.

I'm curious - just from your location I bet you have a higher btu demand than I do, but how long does your 1000g storage carry your house?

 

[Highroad281]

What do you have now for an oil boiler, and how old is your oil tank?

I got rid of my oil all together, and replaced with an electric hot water heater for DHW (when I'm not burning), and an electric boiler for backup heat (1 year old, $400 used on Kijiji). Last winter the electric boiler was only used for one day, when we were away for two - if I had 1000 gallons of storage (rather than the 660 I do have), I might have made it coasting on storage the second day too. I would not want to heat for any extended amount of time on the electric boiler, they can really make your meter spin, but the one day wasn't noticeable on the power bill. It was an easy install.

Couldn't be happier to have sent the oil man packing. It took one chimney out of the need equation, freed up a ton of space in my basement, got rid of all oil related liabilities (your insurance might be cheaper with no oil tank on your property - might want to check that out), and the electric hot water heater heats DHW way cheaper than the oil boiler with coil in it.

I think the only way I would consider keeping an oil boiler, would be if it was a newer cold start one, and I had a fairly new oil tank, and the house was frequently unoccupied during the winter - but even on the last point, I think I would lean towards a mini-split heat pump for some backup heat before an oil boiler.

I was also looking at mandatory oil tank replacement within the next two years, that was also another factor. If that is something you'd be looking at in the near future, you could likely put in an electric boiler & hot water heater for close to what an oil tank replacement would cost - and save money on lower operating costs (don't forget oil burner maintenance & service) and maybe reduced insurance rates (oil spills are pretty big dollar payouts for insurance companies). Also, with oil, you're tied to oil - with electric, you're potentially accessing multiple energy sources, like nuclear, hydro, wind, & natural gas (depending on the individual utlility, that is). If not right now, at least in the future.

My 2 cents.

Maple, it sounds like you're right where I hope to be!

The boiler is a 17 yr old WM gold/carlin that has been problematic at times, and the tank is older than that. It looks to be in decent shape, but they all look good on the outside, right?

Honestly I'm having trouble wrapping my head around how these boiler and storage systems can cost upwards of $20k after all said and done, and folks buying them still don't consider them to be reliable or convenient enough to be a primary solution. It's a little bit of a lifestyle commitment, but I feel like we're already there and will be for the next ~20 yrs or so at least. Good to hear your experience, thanks for chiming in.

 

[__dan]

I would like to know the answer to this also, if you can heat exclusively with cordwood primary and not have another central heat source. I'm pretty sure the answer will come from the building code requirements for your CO, certificate of occupancy, so you will have to ask the local or state building officials office for the code requirement. As far as I know you need a central heat source, you cannot have a residence without it, and cordwood appliances do not qualify towards this requirement. This is the question you need answered. You need to ask the town or state BO's office. I would like this answer also.

A conventionally built and insulated house without heat in the winter, you will get pipe freezing in CT. A super insulated house with a complete wrap of 2" rigid foam board like my house, in Ct, you could go the entire winter with no heat and no pipe freezing. The house gets some heat from the foundation which moderates the temp and keeps it above freezing.

This is to say it is possible to build a freeze proof house, new from the ground up. It depends on the house construction methods, how much supplemental heat is needed to prevent freezing when the wood heat is down, but it could be just a few small electric baseboards in the right locations, bathroom, kitchen, basement near the boiler. But repeating again, a conventionally built house will get pipe freezing without sufficient heat.

 

[avc8130]

I installed a Wood Gun last winter because I only had 1 flue so I needed a combo wood/oil in one unit.

When I spoke to my home owners insurance company, they told me there would be no issue as long as "oil" was the "primary" central heating system. I just use my "backup wood" very often .

I dilly-dallied and to this day still do not have the oil gun hooked up completely. My family doesn't vacation much in the winter. We don't spend too much time at home on Christmas Eve/Day so in the morning on Christmas Eve (~7AM) I packed my E-180 with wood and we left. By the time we got home at 2AM Christmas Day the boiler was pretty much out of wood and cool. The house was <2 degrees colder than the set point on the thermostats. No big deal. I certainly preferred this to having burned $30 worth of oil just to keep the house exactly at 70F when I wasn't even there. I loaded wood and the house was warm by the time everyone had their pj's on.

I have no storage other than the extra wood capacity in the firebox.

I am working on my oil setup this year, mostly just because I want to futz with the boiler and this is an excuse.

ac

 

[__dan]

To answer your other question, I have the oil boiler fully plumbed in complete ready to go, but the wiring is disconnected. I have no desire to burn oil and it's not on my mind. I could make some temporary sloppy connections in 20 minutes and get it running in auto, but it's not on my to do list. The permanent, auto run programmable smart controls are a bit more work remaining.

The Tarm with storage you are planning sounds great. I would think your wood consumption will go down (efficiency up) and your oil burn could be zero. You may need the oil backup to satisfy the code requirement. You are on the right track.

The Tarm will also burn nastier pieces of wood that would never go in the woodstove. I've been burning the lowest quality wood in my yard first, cleaning the yard, and I'm under three cord for the year.

 

[Highroad281]

When I spoke to my home owners insurance company, they told me there would be no issue as long as "oil" was the "primary" central heating system. I just use my "backup wood" very often .

I would like to know the answer to this also, if you can heat exclusively with cordwood primary and not have another central heat source. I'm pretty sure the answer will come from the building code requirements for your CO, certificate of occupancy, so you will have to ask the local or state building officials office for the code requirement. As far as I know you need a central heat source, you cannot have a residence without it, and cordwood appliances do not qualify towards this requirement. This is the question you need answered. You need to ask the town or state BO's office. I would like this answer also.

A conventionally built and insulated house without heat in the winter, you will get pipe freezing in CT. A super insulated house with a complete wrap of 2" rigid foam board like my house, in Ct, you could go the entire winter with no heat and no pipe freezing. The house gets some heat from the foundation which moderates the temp and keeps it above freezing.

This is to say it is possible to build a freeze proof house, new from the ground up. It depends on the house construction methods, how much supplemental heat is needed to prevent freezing when the wood heat is down, but it could be just a few small electric baseboards in the right locations, bathroom, kitchen, basement near the boiler. But repeating again, a conventionally built house will get pipe freezing without sufficient heat.

I'm with you Dan. You can make sensible improvements to a building envelope that will help prevent freezing, but there aren't many houses in northern climates that you can leave as is for an extended period in the middle of winter without any worry at all. For kicks I'd like to poll the HVAC and plumbing pros on the list to find out what percentage of their pipe freeze calls and problems are at houses with "conventional" fossil systems vs these "uncivilized" stick burners with storage LOL. I guarantee guys running these systems are generally a very hands-on group and keenly aware of what it takes to not freeze pipes and are likely a WAY better risk for insurance companies than other individuals who are more suitably programmed for the Condo life...

 

[maple1]

In my case there's a bigger risk of freeze up from extended power outage, rather than nobody being home.

So I'm way ahead of that game with my wood fired system that can burn and convection flow without any power.

There are lots of people with the 'conventional' heating systems that insurance companies & code people like who are in a world of icey trouble when the power goes out for a couple of days mid-winter.

 

[JP11]

I'm curious - just from your location I bet you have a higher btu demand than I do, but how long does your 1000g storage carry your house?

BTU demand is about 90k per hour when it's -10 outside. So it's about 8 hours or so at worst case. Gets longer as it warms up. One fire a day most days. One every 4th day or so in summer.

JP

 

[Gasifier]

Highroad. What are your winters like in NE CT? Average temp? What is wind like around your area where you live? What would you need if you all of a sudden had to leave for 3 or 4 days when it was 10 degrees outside?

 

[avc8130]

If you had to leave for 3-4 days and it was 10 degrees out, you could probably just run a circulator pump to prevent freezing.

OR...if you are doing an electric DHW you MIGHT be able to shut the T-stats, open the zone valves, and use the hot water heater to maintain "low" temp water (as low as it will set) pumping in the zones.

There are many ways to prevent freezing pipes without burning a bunch of oil if the OP wanted to.

ac

 

[Highroad281]

BTU demand is about 90k per hour when it's -10 outside. So it's about 8 hours or so at worst case. Gets longer as it warms up. One fire a day most days. One every 4th day or so in summer.

JP

Good to know. We might see -10 overnight for just a couple days/year, and for another month we may see a low average of 15. I figure my BTU load to be 70K max, so one fire per day or less seems realistic based on your experience.

 

[Gasifier]

If you had to leave for 3-4 days and it was 10 degrees out, you could probably just run a circulator pump to prevent freezing.

OR...if you are doing an electric DHW you MIGHT be able to shut the T-stats, open the zone valves, and use the hot water heater to maintain "low" temp water (as low as it will set) pumping in the zones.

There are many ways to prevent freezing pipes without burning a bunch of oil if the OP wanted to.

ac

If you wanted that type of system. I suppose. I would rather have a solid backup that would not just keep things from freezing, if you are there you and yours would still be freezing. What if you had issues with your wood burning boiler? Or another part of the system to that? I guess a back up wood stove like I have would do the job cheap enough. Whatever works best for him. If he already has the oil boiler and it works fine then that is probably cheapest route.

 

[JP11]

Good to know. We might see -10 overnight for just a couple days/year, and for another month we may see a low average of 15. I figure my BTU load to be 70K max, so one fire per day or less seems realistic based on your experience.

I also have a 60kw boiler.. which holds near a million BTUs if absolutely full. Now.. I can't run the storage up to 195.. then fill the boiler full of wood and let er go all night. The boiler is oversized so as to provide heat to storage and heat to the home simultaneously. It's a learning curve. On a very cold night I can have the storage in the 150s... stuff the firebox full, and go back 10 or 11 hours later and storage is in the 150s and all the wood is gone. Of course, all of my "experiments" were done last year when I was burning marginal wood and softwoods.

There's no cut and dried answer to tell you how your system will work. There's some thermodynamics and calculations that can tell you what's POSSIBLE. I used to be able to do the numbers in my head. It's been a while since last winter. Figure my system is 1075 gallons, (boiler, piping and tanks) x weight of water per gallon x degree spread I use the storage ( I routinely run it up to 195, and it kicks out about 140) so 55 spread.

That gives you stored BTUs. Now that's NET, it's all in the water, no more transfer to figure out. Now.. if it's really cold and you're running the boiler at night, You get X hours till the wood is gone, then your storage starts getting used up after the wood fire is out.

It worked very good in practice on cold nights for me. As I said, all of mine was crap wood last winter. Looking forward to his year and future since I'm at least 2yrs cut and split ahead and still cutting.

JP

 

[__dan]

Freeze risk would be plumbing installed "in" outside walls and under crawlspaces. Sometimes raised ranches have the living floor cantilevered out, and plumbing concealed in that space, hanging out in the cold, with very little except the sheathing and siding between it and the freezing weather, those pipes freeze up.

Exposed porches covered up and converted to living space, with plumbing runs, a shower added with plumbing in the outside walls, that's a freeze risk.

The heating system pipes run all in the conditioned living space are less of a freeze risk.

But the question goes back to what the code will allow, if cordwood cannot qualify as a required central heat source. You have other choices, maybe yank the oil and install a few electric baseboards or a minisplit heat pump, for the code compliance. Yanking the oil completely will make the gasser install easier, if ultimately the gasser as primary is the desired result.

It's 29-250 something in the Connecticut General Statutes, code interpretations are provided to any person on request by the State Building Official's Office. Yanking the oil would be a good plan, you will just have to talk to the town or state BO's office to see what is necessary as a qualifying heat source, per code.

 

[hobbyheater]

Hi All, I'd like to hear some thoughts on this from folks who are actually living it
I'm really leaning towards removing the oil unit completely
There must be some reason that most prefer parallel installs,Looking forward to your insights!

Have used oil with a DHW coil in series with a wood boiler and found out the hard way that in series, it took 4 cords a year just to keep the oil boiler hot. HUGH stack loss. Parallel is more efficient.
When storage was added, the oil was only used as back up and it became unreliable due to lack of use. The furnace oil started to gel!
Now I have an electric boiler back up. Switch over is manual; open one ball valve, close another and turn on one breaker! Simple and reliable!
There is a DHW coil inside of the storage that preheats water to an electric hot water tank. There is an anti-scald valve between the coil and electric hot water tank .

 

[Gasifier]

Have used oil with a DHW coil in series with a wood boiler and found out the hard way that in series, it took 4 cords a year just to keep the oil boiler hot. HUGH stack loss. Parallel is more efficient.
When storage was added, the oil was only used as back up and it became unreliable due to lack of use. The furnace oil started to gel!
Now I have an electric boiler back up. Switch over is manual; open one ball valve, close another and turn on one breaker! Simple and reliable!
There is a DHW coil inside of the storage that preheats water to an electric hot water tank. There is an anti-scald valve between the coil and electric hot water tank .

Yes. You are correct Alan. The oil boiler should be fired on a regular basis. I usually fire mine up every other week or so. They need thier exercise just like us.

 

[JP11]

Yes. You are correct Alan. The oil boiler should be fired on a regular basis. I usually fire mine up every other week or so. They need thier exercise just like us.

I need to let my oil kick over every few weeks this year. I went several months and I had issues with the pump being stuck. I could spin it by hand a few revolutions, and it would fire back up. It's not a good backup unless you can trust it. Need to just plan some days to let the storage go all the way down. That's why I oversized the boiler.. I wanted the ability to "catch up" by charging storage AND heating the full load of the home at the same time.

JP

 

[woodsmaster]

only backup I have is some electric heaters. went on vacation last winter and had a friend stop over and fire the boiler a few time while I was gone. I could have used the electric but didn't want a large bill when I got home. I've run the boiler a few years now and haven't needed a backup. If something would break I think I could have a part in a few days or less.

 

[Highroad281]

Just wanted to thank you all for chiming in and sharing your experiences, as well as the potential pitfalls and gotchas of removing the fossil backup. You all have helped to convince me that for our situation and lifestyle, that removing the oil burner entirely is going to suit our family just fine. I concede that it's not for everyone, but is a choice that I now feel more confident making.

As a summary, here are some of the key decision points:

The existing oil system is way over sized, out dated, and just keeping the boiler warm to heat domestic HW costs close to $1000/yr. I've learned from threads here that most of that is likely stack loss. It runs on a power vent, and sounds like an airplane taking off in the basement every time the boiler lights and drives us nuts.

All my plumbing runs are concentrated in internal spaces, and would be easy to heat with a couple plug-in electrics if we had to be away for an extended period in winter. I will be keeping my eyes open for an electric boiler on CL and stubbing in connections and shutoffs for one when piping in the wood boiler, just for convenience.

The local building official doesn't care what I do as long as the end result passes code, and I understand the risk that the insurance company won't be sympathetic if we did ever have a pipe freeze event. But if the pipes never froze when they weren't being used for heat at all (because we currently heat with a wood stove anyway), they're much less likely to freeze when in use after piping up the Tarm!. And if we do ever decide to sell, I would likely be asked to replace the existing boiler anyway, so the next people can have a credit towards installing the boiler of their choice, bc I'm taking this one with me!

And finally, if there ever is a problem with the boiler that results in extended down time we can resort to using the wood stove that we've been using all along as a backup for heat. So, now I have a topic for another thread to start about rebuilding my open storage tank. Hope to hear from all of you again!

 

[DBNH22]

I recently had a pellet boiler installed along side my existing oil boiler. I decided to keep the oil boiler for several reasons; we wanted a backup heat source if the pellet boiler ever goes down, we will be using it for DHW in the summer for the time being until we find a more cost effective solution, the oil boiler is only 12 years old and in good condition so if we ever sell the house we wouldn't want potential buyers being discouraged by the effort tneeded to obtain the pellets, store them and feed them into the boiler.

It sounds like you have a very old, inefficient oil boiler so maybe it actually made more sense for you to get rid of your's.