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alscats

replace Oil Furnace with Propane 2 stage hot air furnace.

alscats
11 years ago

I need a new boiler and it was recommended by the energy auditor that I get a new high efficiency hot air propane furnance, get rid of baseboard and get duct work. We are getting ready to do a remodeling project and wanted a ventless propane boiler and then Mr. Slim zoned mini splits(heatpumps). The propane hot air furnance was the recommendation and when I asked why they said well your copper pipes could leak? I love my base board hot water heat and my boiler, when it worked, was instant hot water and instant warm rooms? Changing to a forced air system seems breezy, dusty, and chilly to me? Any one know about a change like this?

Comments (21)

  • tigerdunes
    11 years ago

    I assume you have an oil fueled boiler now.

    What are you paying for fuel oil?

    What is cost for propane?

    What is your electric rate? You are aware there are electric residential boilers.

    Of course with forced air heat pump systems-split or mini splits you do get AC. How important is that to you?

    I would not get rid of baseboard hot water eat if you like it.

    Pst back your fuel costs.

    IMO

  • mike_home
    11 years ago

    "The propane hot air furnace was the recommendation and when I asked why they said well your copper pipes could leak?"

    He is not a very credible energy auditor if he makes statements like this. In my opinion he is giving you bad advice.

  • tigerdunes
    11 years ago

    Have to agree with above post. Leaks can occur but that's no basis for a forced air system unless one has a history of trouble. Typical statement though from many dealers looking out for themselves and not listening to homeowner and their best interest.

    IMO

  • alscats
    Original Author
    11 years ago

    Our 1963 oil boiler has a domestic hot water coil that is busted, we have already replaced it once and we have problems finding someone who wants to work on it. We wanted during this upcoming remodeling project to get a tarm wood gassification system but that is over $25K installed, then I need to find someone to install it.

    The oil I pay a flat $350/month - I want to say it is $2.78/gallon.

    I do not know the propane cost but have read in the local paper it is about the same as oil in our area.

    In the remodel I mentioned we are getting solar panels{{gwi:807}} that should provide about 65% of our annual electric. Our electric rate we have depends on when we use it - lower rate depending on time but average is 10.2/kwh

    The mini splits for zones were for air conditioning and then since they would be heat pumps used as back up. The air flow of the house keeps it pretty cool and the window units we have been using are only on as needed. I do not want everything remodeled in my house and then stick a AC unit in my new window and since we have the baseboard heat that is why I wanted the mini splits.

    This house is the warmest we have ever had and the baseboard heat is awesome. And pipes regardless of how old ect, can always get a leak. I donot have any good information about the newer heat pumps and have not heard of this gas hot air furnace as a back up to a 18 SEER heat pump at all.

    any info is helpful.

    This post was edited by alscats on Wed, Jan 23, 13 at 14:36

  • tigerdunes
    11 years ago

    If operating costs are important to you, I would look into an electric boiler..

    Of course with an electric boiler and HP mini splits, a good dealer and or electrical contractor will need to look at your electric supply panel for capacity. May need modifying.

    I question that fuel oil price. Mighty low.

    Do you mind providing your location?

    IMO

  • alscats
    Original Author
    11 years ago

    I will look it might be as much as a $1 more - since I pay the flat monthly rate and can't really do much about the price once I lock it in (it will lower but no go above if you lock it in) I don't look at it.

  • mike_home
    11 years ago

    Would it make more sense to use the new mini-splits as the primary heat source and use the hot water baseboard as the back up heat?

    I would also investigate a new oil fired boiler. The choices of an electric boiler for residential use may be limited. You will probably need to upgrade the electric feed to your house to power the electric boiler. You need to factor this into your decision. You could get an electric hot water heater if you want to minimize your fuel oil consumption.

  • alscats
    Original Author
    11 years ago

    Thanks - the electric boilers I found were the 'tankless' wall mounted ones - then I found a Rannai boiler - propane one - I will check and see if that can loop with the solar thermal tubes & storage tank and that might work - the mini splits would I am sure do some heating especially during spring summer when there would be no reason to use the base board. Unless the tubes provide enough for hotwater & heat with out the gas kicking on .

  • ionized_gw
    11 years ago

    All I can say is, nuts! Is this an independent energy rater or one from a company that installs a lot of $ducts?

    Install ducts AND mini-splits? If you are going to ducts, why not central AC? It would probably be less expensive though there are inherent advantages to the mini-splits. One advantage is the inherent zoning. For example, if you are heating only the bedroom at night, your boiler might not have to run enabling lots of savings. Someone creative is going to have to think it through though since when it gets very cold, the HP might not be able to work efficiently and it will take some custom controls to make a call to the boiler for heat. It certainly can be done with separate zones or just a second thermostat.

    Baseboard is very, very nice, though modern forced-air equipment with a good installation is better than in the olden days.

    Dad has a 1959 Crane Sunnyday boiler that seems to be going strong. I can't say how many coils or burners it has gone through. He has been blessed with great service over the decades. If you make the heat pumps your primary heat source, yours could last as long as you can find parts, but it seems like you might already be past that point. If domestic oil heat is getting sparse in your area, I suppose you have to give up if service people are all dying off.

    My understanding is that PV has gotten so inexpensive that it makes more sense to use it to heat water with a conventional water heater than to use solar thermal. The up front cost is higher, but the solar thermal has so many moving parts that you recoup the costs in maintenance and repair. The same should hold true for space heating with PV vs. thermal. That must be doubly true in cold climates where evacuated tubes would be necessary for solar thermal.

    If propane costs are similar to oil for the fuel alone, propane probably wins. Higher efficiency boilers can be found and for available service people (from your information). It probably needs less maintenance since it burns cleaner.

  • alscats
    Original Author
    11 years ago

    Not ducts & mini splits - i wanted to replace the oil boiler with a gas boiler and get mini splits for AC & of course they come as a heat pump so I then have heat. The solar panels will have some solar tubes for hot water and that needs to work with the boiler system I get. I like the electric boiler 'backpack' systems I found after a recommendation here and the Rannai wall mount gas unit looks nice also. Trouble is finding someone who will give me a good recommendation on what works best and not just what they sell. My older boiler repair man retired and the other service places I call don't want to work on the boiler. :(

  • ionized_gw
    11 years ago

    Again, make sure that you do the arithmetic to be sure it is not less expensive over the life of the equipment to install PV and use an electric water heater. With PV prices decreasing so much over the past few years, this has been a moving target.

  • david_cary
    11 years ago

    The obvious should be stated - the absolute cheapest way to heat your house is geothermal. It should at least be considered. Next cheapest is air source heat pump particularly with an efficient mini split.

    It seems to me that converting the whole house to a standard ducted heat pump has a fairly low upfront cost and a fairly low run cost. It is a compromise for upfront cost and ongoing cost.

    I can't see why anyone would recommend propane - unless the goal is having generator backup heat.

    Are you talking paying $350 for 12 months? A heat pump with electric backup should be 50% of that or less depending on climate and what system you buy. It would seem like Carrier Greenspeed would pay off for such a high heating need. You would probably save closer to 75% compared to oil. So even though it might be $20k installed, the payback is 7 years.

    You really need to experience a well installed forced air system. I don't know mine is on. I fail to see how a gentle circulation of air through a filter creates dust - it actually reduces it. And then it humidifies it.

  • tigerdunes
    11 years ago

    I am going to take a little different approach.

    If homeowner wants to keep heated baseboard hot water heat, then what is the most cost effective fuel choice to accomplish this and type of boiler?

    If homeowner wants AC then does he have the space to add a ductwork system for a forced air system? And how does he feel about adding a ductwork system? And obviously if he proceeds with AC in a split system
    or mini splits, then he might as well make this a HP system both for redundancy and the AC for cooling.

    He will have to have his electrical supply evaluated for possible modification and upgrade.

    IMO

  • ionized_gw
    11 years ago

    Is the climate right for mini-splits?

  • ionized_gw
    11 years ago

    Oops, I meant, is the climate right for heating with heat pumps?

  • alscats
    Original Author
    10 years ago

    Update:
    Oil Furnace is DEAD
    A lot of the old wall to wall baseboard needed to be removed during construction - most of the house needs to be gutted down to studs for reasons I do not currently understand. That said, I cannot change the fact that most of the wall to wall baseboard is not gone and needs to be replaced, I am going to visit geothermal, but the propane forced hot air is what is being recommended, due to air quality becoming more of an issue? or a buzz word, yet to be determined.

    thanks all for posting and keep at it, I have to make a decision now in the next few days. but the forced propane 90+% efficiency with air quality controls and ability to reverse flow in winter & summer is looking pretty good, but making me nervous, I have yet to feel a good system. These newer ones are supposed to be better.

  • jackfre
    10 years ago

    You like the comfort of the hydronic baseboard. Look into the Rinnai combi boilers. They will do both heat and hot water. Use the mini-splits as well. You will find that with the mini-splits you will only run the central heat on occasion. WHERE ARE YOU? It makes a difference. BTW, with the re-model in full swing I would look at aa product called Warmboard. You could then have radiant heat in the floors. The front end cost of geothermal are to high, imho, and with the mini-splits you will be tickling the efficiencies of the geothermal for substantially less up front cost.

  • ionized_gw
    10 years ago

    Forced air allows you to have controlled ventilation throughout the house. It becomes more important with well-sealed structures.

    The trouble with having mini-splits with a completely separate back-up heating system is that unless it is simple electric resistance heaters, it will get mighty expensive very quickly. Note that I believe that some mini-splits have back-up resistance heat. Also note that with a tight house your heating and cooling systems don't have to be very efficient. That goes double for back-up heating systems.

  • jackfre
    10 years ago

    Ionized, none of the top brands of mini-splits have back-up electric heat. Years ago some did, but US codes do not allow supplemental elec heat in a plastic cased unit.

  • ionized_gw
    10 years ago

    Good to know, Jackfre.