Gas insert worth the costs?


  #1  
Old 01-04-14, 11:51 AM
N
Member
Thread Starter
Join Date: Feb 2008
Location: USA
Posts: 78
Received 0 Votes on 0 Posts
Gas insert worth the costs?

We recently purchased a new home. 2 stories, 2300 sf. We have an electric heat pump with back up resistance coil heating as the primary heat source. It was installed 3 years ago. The house was built in 1993 with a prefab wood burning fireplace in living room. Previous owners installed gas log set in the fireplace and they barely put out any heat. We are considering installing a direct vent insert but I want to know if it will save me any money. All I've ever used in the past was wood.

We would like to be able to keep the living room warm and maybe the master bedroom that is right off of it. The living room is 16x25 with 10 foot ceiling. Don't use the rest of the house much this time of year so not as worried about keeping them warm.

Already have a 100 gallon propane tank (owned) and gas line ran to the logs.

We live in indiana and have 3 cold months per year. Temps can be high around 30 and lows in the teens on average.

So in this scenario would we be able to save much money on heating costs using an gas (propane) insert? How much should we expect to pay for an inset and installation? How much propane would it burn per hour? Any specific model recommendations?
 
  #2  
Old 01-04-14, 01:56 PM
P
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 25,299
Received 909 Votes on 837 Posts
Everything depends on what you choose. Without knowing that it's hard to answer any of your questions since the key is missing but we can talk generally.

Your current wood stove with gas logs is probably very inefficient so replacing it with a modern vent free system is likely to be an improvement. Will you save any money? Do you know how much you spend running your current gas logs and how much heat you actually get into the room? If you don't know than it's impossible to say if anything else will save you money other than to say it probably will.

How much propane would it burn per hour? How much fuel does an airplane burn per hour? A Cessna 172 or a 747? Again, it depends on the gas stove you choose. Propane contains about 21k btu per pound and about 91k per gallon. If you choose a 30k btu stove it will use about 1/3 gallon per hour. Multiply the stove's btu by it's efficiency and you'll get an idea of how much heat will make it into your house. Carry the math a little further knowing how much you pay for propane and you can figure out how much the heat costs you and if it's less expensive than running your heat pump.

Vent free stoves are almost 100% efficient meaning almost all the heat of flame is put into your room. Obvious since there is not vent so there is nowhere else for it to go. The tradeoff for that efficiency is that the combustion exhaust is going into the room. It's considered safe and approved in most areas like a gas kitchen stove but some localities do not approve them and some people fear the exhaust gasses. I have had a couple for over ten years and love the humidity they add to the house in winter. One of the big byproducts of combustion is water so you get a free humidifier. You'll hate it though if you get a batch of contaminated propane which can smell as it burns.

Direct vent inserts and stoves are nowhere near as efficient as vent free as some portion of the heat goes out the flue. You should easily find a stove north of 80% efficient. Not bad and certainly better than your current gas logs but not great compared to a modern high efficiency furnace and not the 99.9% level of vent free. What you give up in efficiency you gain in peace of mind knowing that you are not breathing the exhaust gasses and you have a heat source that will work when the power goes out.
 
  #3  
Old 01-04-14, 03:53 PM
lawrosa's Avatar
Super Moderator
Join Date: Dec 2010
Location: Galivants Ferry SC USA
Posts: 18,159
Received 69 Votes on 61 Posts
so replacing it with a modern vent free system is likely to be an improvement.
I never recommend any vent free device for health and saftey reasons..period...



I dont think you will save much using a propane insert... If not it may cost more...

Whats your electric rate?

IMO if you can do the work a wood insert would be best... especially if you do the labor to cut the wood.. There is so much free wood out there...

Better then an insert IMO would be a regular wood burning stove............
 
  #4  
Old 01-04-14, 04:14 PM
N
Member
Thread Starter
Join Date: Feb 2008
Location: USA
Posts: 78
Received 0 Votes on 0 Posts
We pay around 8 cents per kWh for electric

Propane runs about 1.60 per gallon
 
  #5  
Old 01-04-14, 07:07 PM
G
Member
Join Date: Dec 2007
Location: USA
Posts: 239
Received 0 Votes on 0 Posts
Gas insert worth the costs?

"gas log set in the fireplace and they barely put out any heat" That means the heat went up the chimney.

Vent free is really not an insert, it is a set of burners like on a stove top you place in your fireplace. There is no chimney so they vent directly into the room. One problem with them is they produce a lot of water vapor, like 1 gallon per 100,000 BTU if I remember right. On the other hand people pay good money for humidifiers so some water vapor is not a problem. Another is they burn up anything floating in the air and vent it back into the room air.

*************** removed info**************

Although vent free systems claim to have oxygen sensors, it really is just a heat sensor that confirms the pilot is working so I assume your logs have the same thing.
 

Last edited by lawrosa; 01-04-14 at 07:19 PM. Reason: Removed venting info...... Post archived
  #6  
Old 01-04-14, 08:17 PM
B
Member
Join Date: Oct 2008
Location: New England
Posts: 10,524
Received 37 Votes on 34 Posts
Hi newguy,
Since you did say direct vent the vent free is correctly not under consideration. Your propane and electric are reasonably close in close (I'm jealous we are double) but there is a savings by targeting the heat to one room vs heating the entire house to 70. Plus, is your insert or stove can run without electricity it give you that peace of mind having a bad weather backup.

When you shop for either an insert or wood stove they will have BTU ratings. Too small and it will be lost in that size room. A little math and you can determine what size is required. There are folks here that can help with that.

I use wood and deal with the work required, although age is making me look at perhaps a pellet stove. I would add a back-up power source as they do require some electricity.

Let's see where you are leaning and then discuss it more.

Bud
 
  #7  
Old 01-05-14, 04:11 AM
P
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 25,299
Received 909 Votes on 837 Posts
Propane vs Heat Pump: Based on your costs I crunched some numbers. You get about 91'000 btu for your $1.60 a gallon propane. If you pick an insert that is 85% efficient then you are getting about 72'000 btu's into the home for your $1.60. Using this .pdf from Duke Energy I picked a 13 seer heat pump and the same 72k btu will cost you about $.73 ... less than half the cost of propane. But, when it's like 0f outside you are running almost completely on your emergency heat strips which cost $1.69 to make 72k btu even assuming 100% efficiency so when it's really, really cold outside propane finally becomes less expensive.

---

Accurately calculating which is cheaper to operate is very difficult with a heat pump. Heat pumps become less efficient as the outside temperature drops and must run longer to produce the same amount of heat when it's cold outside. So, the cost to operate will change depending on the outside temperature. A propane stove or insert burns a fixed amount of fuel so it's pretty easy to figure.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: