With folks turning to the Internet more frequently, it's not unusual for customers to have a pretty good idea of what they want before they call you. For example, here's an e-mail from a customer: "We're interested in lowering our heating costs and considered the (brand name withheld) fireplace because of their ads claiming 50% savings. Seems a bit far fetched and lots of Internet push-back, so we're not exactly enamored. Natural gas is available and we really like the looks and stated efficiency of the Rinnai fireplace, www.rinnai.us/fireplaces/rhfe-750-direct-vent-fireplace. Two things: how soon can you stop by to provide a quote, and we both need to know how much we can shave off our heating bill."
Their last sentence set the stage for what was required: a Manual-J heat loss calculation; gather existing equipment information for the boiler; and operating cost projections based upon how far they are willing to set back their home's thermostat while maintaining comfort in the selected area. First step was downloading the installation and operating manual while also learning what options are available and follow that with scheduling a visit. All of which took less than a half-hour's time: the internet is a valuable resource tool for contractors too!
Manual-J revealed a 79,928-Btuh heat loss on a design day and the boiler being used was rated for 92% thermal efficiency, but their radiant hydronic system was installed using staple-up, which resulted in a need for 160°F water-delivery during colder weather. That adversely impacts the boiler’s thermal efficiency and likely reduces it to 83%, the same operating efficiency as the Rinnai fireplace. If this was an accurate assumption, then their annual operating cost for an average heating season should be $2,419.15 with natural gas at $1.45 per ccf and 2,250-run-hours. They have three in the family, which requires backing out the cost for DHW: using 60-GPD resulted in $413.69 for their direct-vent water heater. Reviewing their gas usage over several years' time revealed we were on target.
When you read the fine print for the portable electric fireplace the energy savings are based on setting the home's thermostat to 50°F! Really? To give an apples-to-apples comparison, our customers' heat loss would be 55,508-Btuh with an annual operating cost of $1,608.04, a reduction of 33.5%, not the 50% suggested in the ads. The ECV (energy conservation value) = $811.11
The area they will be heating with either the Rinnai gas fireplace or the electric fireplace will require 3,557-Btuh be provided by either fireplace to boost the area from 50°F (provided by floor-warming) to 72°F. The operating costs: $107.66 for natural gas and $216.77 for electric. Installed costs: $4,000 for the Rinnai and the electric fireplace (internet sale) $423.99 (no involvement for a contractor). In other words, they needed to be persuaded that up-front cost-difference of $3,576 would be a smart investment.
Like most folks, they're not planning on moving or selling their home and are firmly rooted in their neighborhood where their daughter has lots of friends her age. Enter the power of ROI (return on investment)! If we assign a 5% per year increase in fuel costs and run a 20-year projection, the Rinnai gas fireplace will have an operating cost of $3,559.88 while the electric fireplace will consume $7,164.40. The $811.11 ECV projected over the same 20-year span with a 5% per year increase totals $26,820.13. ROI equals difference-in-cost 3,576.00 ÷ (ECV 26,820.13 – Operating-cost 3,559.88) = 15.4%. Payback will occur in the fifth year.
A number of other features built into the Rinnai fireplace had grabbed their attention: a seven-stage modulating gas valve to better match output with heat-loss to reduce burner-cycling; direct-venting with combustion blower, which reduces operating costs and ensures balanced combustion; a variable-speed whisper-quiet blower; and programmable wireless remote controller. From my perspective, the clearance from an operable window was vitally important and Rinnai’s I&O illustration revealed just 9-in. clearance was required and the exhaust vent assembly required zero clearance from combustibles. That turned out to be a great asset due to a wall-stud being a close-shave for the exhaust/intake vent assembly. Vinyl siding on the exterior was a concern on two fronts: ensuring the penetration could be centered on a single panel; and deforming the vinyl panel when drawing the inside/outside flanges together to form a weather-tight seal. After drilling the hole through the vinyl siding and exterior wall, expanding foam was used to fill the void space between siding and plywood. Because there was no barrier to expansion, the foam simply oozed out where the siding was cut and set up to form a solid backing.
The gas line was run using ½-in. black-iron piping due to recent concerns regarding CSST and lightning strikes. The cost difference was virtually the same with the additional two-hours time required for installing black-iron piping with just two cut/threaded pieces required. Black-iron developed length with 4-ells and 1-tee totaled 90’ and delivered capacity = 53,000-Btus, which exceeds the 28,000-Btu maximum line-load for the Rinnai fireplace (http://contractormag.com/piping/mechanical_lightning_groups).
If you're not selling and installing gas fireplaces, you may want to add them to your offerings.
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