Transitioning Between Propane and Electric
After a year of house hunting, we finally landed a home within a school district of choice. The home is set to deliver in April 2023 and fingers crossed the propane prices drop by then. Not too hopeful on that price drop, so I began looking into this HVAC topic more closely. The home is in the Philly suburbs, so I think Zone 4A.
1. We are tied to propane for heat, cooking, fireplace, water heating (Navien NP240A tank less). Dual zone heat with 2 Lennox ML193UH070 furnaces and 2 Lennox 13 SEER AC units (model 13AC XN030-230-26). I got an electric connection for the dryer.
2. The builder has locked us into a tank lease for 2 years and the propane price is based on the Non – TET TX Mont Belvieu propane index +$1.35 which at the moment comes to about $2.5 per gallon. We cannot change the heating system on the house and any such change would trigger a $5200 “removal” fee by the propane supplier and I’m guessing they will also remove the tank if they observe that I have used less propane than what they’ve estimated. I will speak with them once more between now and April to see if I can avoid this lease altogether and just buy it out upon moving in. To be figured out. Based on my initial chat with them, the propane supplier has estimated that we will need 4-5 refills a year, so approx. $3000-$3500 annually in propane gas spending for the 3120sqft finished area using the current pricing. Index link: https://fred.stlouisfed.org/series/DPROPANEMBTX
3. Upon completion of this 2-year contract we have the option for a “lease buyout” at $5200 and then finally shop around for propane and get heat pumps. This is my main concern and design question. I will have 2 propane furnaces and 2 Lennox AC units. I plan on swapping those out to Lennox air source heat pumps and somehow finding customers to sell the 13 SEER AC units to – most likely won’t get any decent amount for those units based on what I’ve heard from the few local HVAC guys I spoke with.
4. We pushed to get the Manual J from the builder – and they shared it surprisingly. It is attached. The home is South facing and I have no idea why it says on there that the main door faces west. It also mentions that the basement is finished and it isn’t. My guess after reading for a few hours on this blog and other questions posted on this topic on this forum, is that this is another one of those “Garbage in – Garbage out” Manual J calcs. Can someone verify the calculations?
5. The insulation details are in the attachment. The builder is using 2015 IEC code and has mentioned in an email that they will push for a blower door test with 5 ACH50 or lower. Windows are Plygem silverline and the construction is Tyvek over OSB. Based on some homes I walked through in the construction stage, it seemed like the envelope was pretty tight. I will try and hire a HERS rater and have them accompany me at the pre-drywall walk-through however I doubt that I will be able to obtain the blueprints of the house which are required by HERS raters. Should I skip the rater and just hire a standard new home construction inspector?
6. Once the above questions are answered, how do I go about sizing my heating system and designing my heat system to reduce/eliminate the propane usage?
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