South Salt Lake Rental Property Coordinated 4-Unit Furnace Replacement

Customer:

Jordan Whitmer (property manager, consent for documentation given on behalf of property owner)

Address area:

South Salt Lake, State Street corridor — near 3300 South, mixed-use commercial-residential area

Property characteristics:

4-unit residential complex built 1978. Single-story configuration with each unit approximately 850-950 sq ft, two-bedroom one-bathroom layout. Concrete slab foundation. Wood-framed construction with brick veneer on State Street facing wall, vinyl siding on rear and side elevations. Original aluminum-frame single-pane windows replaced 2014 with vinyl double-pane. Concrete parking area with carport coverage for each unit. Each unit has individual gas meter, individual electric meter, individual residential-grade HVAC equipment in dedicated mechanical closet. Standard South Salt Lake rental property typical of the State Street corridor.

Project type:

Coordinated 4-unit furnace replacement — existing 1978 equipment at end of life across all four units, property owner electing coordinated replacement rather than reactive repair-as-things-fail pattern

Project completion date:

Phased over 6 weeks — Unit 1: August 14-15, 2024; Unit 2: August 28-29, 2024; Unit 3: September 11-12, 2024; Unit 4: September 25-26, 2024

Total cost:

$22,400 total ($5,600 per unit) installed plus $800 Dominion ThermWise rebates ($200 per unit) = $21,600 net cost

Background

Jordan Whitmer manages a small portfolio of South Salt Lake rental properties for an out-of-state owner. This 4-unit State Street complex came into our service relationship through Jordan in early 2024. The property owner had inherited the property in 2022 and had been managing the HVAC reactively — calling for emergency dispatch as equipment failed, paying premium prices for after-hours service, dealing with tenant complaints during failures. By spring 2024 the pattern was becoming clear: 1978 equipment was reaching end of life across all four units, with three units having emergency dispatches across winter 2023-2024. The property owner agreed to Jordan’s recommendation for coordinated phased replacement, which is what this case study documents.

Existing Equipment (All Four Units)

Furnaces (all replaced):

All four units had original 1978 Coleman residential gas furnaces. 60,000 BTU/hr input each. Approximately 65% AFUE (mid-1970s vintage, no AFUE rating on nameplate, estimated based on era). Natural gas. Atmospheric venting through dedicated B-vent stacks. 46 years service life at time of replacement — well beyond typical residential furnace service life expectancy.

Ductwork:

Original 1978 sheet metal ductwork in each unit. Round trunk and branch ducts. Minimal insulation. Manual D static pressure analysis pre-installation: 0.42-0.48″ WC across all four units (acceptable). No ductwork modifications required.

Thermostats:

Mix of equipment: Unit 1 had 1995 Honeywell Round (mechanical), Unit 2 had 2008 Honeywell programmable, Unit 3 had 2014 Honeywell programmable, Unit 4 had broken thermostat (mechanical Honeywell Round with shorted wiring from tenant DIY repair attempt). All replaced with consistent Honeywell T6 Pro programmable models.

AC matched:

None — this property has window units provided by tenants. Property owner has not historically provided central AC. Manual J load calculation included consideration of potential future AC addition but project scope was furnace-only.

Other:

Each unit has its own 40-gallon natural gas water heater (separate venting). Filter housing on each furnace: 1-inch MERV 5 (basic builder-grade housing). Upgraded during replacement to 1-inch MERV 8 standard.

Diagnostic Findings During Pre-Replacement Assessment (April 2024)

All four furnaces evaluated:

Combustion analysis (Testo 320), borescope heat exchanger inspection, blower motor condition assessment, control board functionality, manifold pressure verification.

Combustion analysis results:

• Unit 1: 320 ppm CO at flue, 64% steady-state efficiency, flue gas temp 445°F. Heat exchanger borescope: visible oxidation, no cracks confirmed. Status: end of life, replacement recommended.
• Unit 2: 285 ppm CO at flue, 67% efficiency, flue gas temp 425°F. Heat exchanger: visible oxidation, possible hairline crack on primary section 2 (inconclusive). Status: end of life, replacement recommended on safety basis.
• Unit 3: 380 ppm CO at flue, 62% efficiency, flue gas temp 462°F. Heat exchanger: confirmed crack on primary section 1 (CO escape confirmed via smoke pencil test). Status: equipment must be replaced; recommended to take offline immediately or replace urgently. This unit had emergency dispatch January 2024 for HSI replacement during cold snap.
• Unit 4: 295 ppm CO at flue, 66% efficiency, flue gas temp 432°F. Heat exchanger: visible oxidation, no cracks confirmed. Status: end of life, replacement recommended.

Unit 3 priority handling:

Heat exchanger crack on Unit 3 elevated this unit to first replacement priority. CO escape via crack means combustion products entering the supply air stream — safety concern. Tenant of Unit 3 was a working single mother with two children (ages 6 and 9). We coordinated with Jordan to expedite Unit 3 replacement and arranged temporary portable heater rental for the 2-week gap between assessment and earliest available installation date.

Decision sequence on phasing:

Phasing reordered post-assessment: original plan was Unit 1-2-3-4 sequential. Reordered to Unit 3 first (heat exchanger crack), then Unit 1, Unit 2, Unit 4 in sequence based on tenant schedule availability and equipment condition severity.

Decision Framework

Coordinated vs. reactive replacement analysis:

Property owner specifically requested economic comparison of coordinated phased replacement vs. continued reactive emergency-dispatch pattern.

• Reactive pattern (winter 2023-2024): 3 emergency dispatches across 4 units (HSI replacements, pressure switch failure). Total emergency dispatch cost: $1,840 ($465 average per dispatch). Plus annual tune-ups: $720. Plus inevitable continued failures in upcoming winters. Plus tenant complaints affecting occupancy and rent collection. Plus eventual replacement when equipment fails completely.
• Coordinated replacement: $22,400 total cost (4 units), $21,600 net after rebates. Eliminates emergency dispatch cycle. Annual tune-ups for new equipment: $580 (lower because newer equipment requires less intensive tune-up). Equipment service life: 18-22 years projected. Operating cost savings from 95% AFUE vs. 65% AFUE: estimated 30% gas bill reduction per unit annually.
• Conclusion: Coordinated replacement pays for itself within 5-6 years through eliminated emergency dispatch costs and operating cost savings, while providing tenant comfort improvement and reducing landlord operational stress.

Equipment tier evaluation:

1. Cost-conscious tier: Goodman GMVC8 80% AFUE — $4,200 per unit installed. Reduced equipment cost but lower efficiency.
2. Cost-conscious 95% AFUE: Heil N9MSB 95% AFUE — $5,000 per unit installed. Better efficiency, slightly higher cost.
3. Mid-tier 96% AFUE (selected): Goodman GMVM97 96% AFUE — $5,600 per unit installed. Best balance of efficiency and durability for rental property context.
4. Premium modulating: Bryant 925SA 96% AFUE modulating — $7,400 per unit installed. Premium equipment, but not necessary for rental property tenant use patterns. Tenants typically maintain single setpoint; modulating capability doesn’t add comfort value matching the cost premium.

Property owner selection:

Goodman GMVM97 96% AFUE selected for all four units. Reasoning: (a) standardizes equipment across the complex, simplifying future maintenance and parts inventory; (b) 96% AFUE qualifies for Dominion ThermWise rebate; (c) single-stage operation simple for tenant use without complex thermostat training; (d) Goodman’s residential equipment has good track record for rental property service life; (e) cost-effective compared to premium tier without sacrificing reasonable efficiency.

Equipment Specifications

Furnace (all four units): Goodman GMVM97

• Model: GMVM970603BN (60,000 BTU/hr input, 96% AFUE, modulating output 35-100%)
• Single-speed PSC blower (standard for cost-conscious mid-tier)
• PVC concentric venting (intake + exhaust)
• 10-year parts warranty (transferable)
• 5-year heat exchanger warranty
• Altitude-derated for South Salt Lake elevation (4,265 ft, 17.1% derate): nameplate 60,000 BTU/hr delivers approximately 49,740 BTU/hr effective output

Manual J calculation results (each unit):

• Unit 1 (north-facing): 38,200 BTU/hr heating load at design conditions
• Unit 2 (south-facing): 35,400 BTU/hr (lower due to solar gain benefit)
• Unit 3 (north-facing): 38,800 BTU/hr
• Unit 4 (south-facing): 35,800 BTU/hr
• 60,000 BTU/hr nameplate Goodman GMVM97 appropriately sized for all four units with reasonable margin after 17.1% altitude derate.

Thermostats:

Honeywell T6 Pro programmable (all four units). Standard residential thermostat with basic programming capability. Selected over smart thermostats because rental property tenants typically don’t engage with smart features; basic programmable provides adequate functionality without WiFi configuration complexity or potential security concerns.

Air filtration:

1-inch MERV 8 filter housing in each unit (replacing original MERV 5 builder-grade). Standard residential filtration, easily accessible by tenant for monthly changes.

Venting:

PVC concentric venting through new exterior wall penetrations (replacing original B-vent stacks through roof). Each unit’s venting designed to be visually unobtrusive on the side or rear elevation (away from State Street facing facade).

Electrical:

Each unit’s existing 100A service adequate for PSC blower current draw. No service upgrades needed. Standard 15A dedicated circuit maintained.

Installation Phasing and Tenant Coordination

Tenant communication protocol:

Jordan coordinated all tenant communication. 30-day advance notice provided to each tenant. Tenant rights respected per Utah landlord-tenant law. Each unit’s installation window scheduled for tenant convenience where possible.

Unit 3 (first — priority due to heat exchanger crack):

August 14-15, 2024. Tenant arrangements: single mother with two children. Temporary portable heater rental from us provided ($35/day) during the 14-day gap between heat exchanger crack identification and installation completion. Tenant absent from unit on installation days (children with grandparents, mother at work). Installation crew: Marcus Halverson + Eli Tran. Installation completed midday Day 2; tenant returned to home with new equipment operational.

Unit 1 (second):

August 28-29, 2024. Tenant arrangements: retired couple, both home during installation days. Installation crew: Marcus Halverson + Eli Tran. Tenants worked from kitchen area while installation proceeded in mechanical closet. Coordination of temporary heat unnecessary in August.

Unit 2 (third):

September 11-12, 2024. Tenant arrangements: working professional, absent during weekdays. Installation crew: Dakota Whitfield + Eli Tran. Standard installation, no complications.

Unit 4 (fourth):

September 25-26, 2024. Tenant arrangements: graduate student, scheduled installation around class schedule. Installation crew: Dakota Whitfield + Reagan O’Donnell. Standard installation, no complications.

Standardized 2-day installation per unit:

• Day 1: Old furnace removal, original B-vent stack removal, PVC venting installation through exterior wall, new furnace placement, gas connection with leak testing
• Day 2: Electrical work, condensate drain installation, thermostat installation, MERV 8 filter housing upgrade, commissioning (combustion analysis, manifold pressure with altitude derate verification), customer/tenant operation education

Commissioning measurements (representative, Unit 1):

• Manifold pressure: 3.4″ WC (altitude-adjusted from nameplate 3.5″ WC)
• CO at flue: 22 ppm (excellent — well within acceptable range)
• O₂ in flue gas: 7.8%
• CO₂ in flue gas: 9.2%
• Flue gas temperature: 128°F (typical for 96% AFUE condensing furnace)
• Steady-state efficiency: 95.4%

AHJ inspection:

Each unit individually permitted and inspected. Permit numbers: B-2024-19002 (Unit 3), B-2024-19847 (Unit 1), B-2024-20885 (Unit 2), B-2024-21924 (Unit 4). All passed inspection on first review.

Cost Breakdown

Per-unit costs (representative, applied to all 4 units):

• Goodman GMVM97 furnace equipment: $1,800
• Installation labor (2 days): $1,400
• PVC venting materials and installation: $345
• Gas connection and leak testing: $245
• Electrical (verification + minor work): $145
• Condensate drain modification: $145
• Honeywell T6 Pro thermostat: $185
• MERV 8 filter housing upgrade: $85
• Permit fees: $245
• System commissioning: $185
• Commercial maintenance plan coordination: $185
• Subtotal per unit: $4,965
• Equipment standardization discount (multi-unit project): -$0 (none, already at lowest reasonable cost)
• Total per unit: $4,965 base + $635 multi-unit project overhead (permits, scheduling, project management): $5,600 per unit

Total project cost:

• 4 units × $5,600 = $22,400
• Less Dominion ThermWise rebates (4 units × $200): -$800
• Net cost: $21,600

Rebates and incentives:

• Dominion Energy ThermWise rebate (Goodman GMVM97 96% AFUE eligible): $200 per unit, $800 total
• Federal IRA 25C tax credit: NOT applicable (residential energy credits apply to homeowner’s primary residence, not rental properties)
• Note on IRA 25C for rental properties: Some federal tax credits do apply to rental properties under different programs, but standard IRA 25C requires personal residence use. Property owner’s tax professional should evaluate applicable depreciation strategies for this equipment investment.

Commercial maintenance plan post-installation:

Property owner enrolled all four units in commercial maintenance plan at $480/year per unit ($1,920/year total for 4 units). Plan covers: annual fall tune-ups (combustion analysis, system verification), priority dispatch for emergency repairs, 15% discount on repair parts and labor, 5-year maintenance documentation for warranty support.

Post-Installation Outcomes

Winter 2024-2025 performance:

• Emergency dispatches across all 4 units winter 2024-2025: 0 (compared to 3 emergency dispatches winter 2023-2024 with old equipment)
• Routine service calls: 1 (Unit 4 tenant reported intermittent operation issue October 2024; diagnosed as installer software update needed on new control board; corrected during regular business hours)
• Gas consumption per unit (estimated, comparing winter 2023-2024 vs. 2024-2025):
  • Unit 1: 612 therms vs. 425 therms (-30.6% reduction)
  • Unit 2: 545 therms vs. 388 therms (-28.8% reduction)
  • Unit 3: 624 therms vs. 432 therms (-30.8% reduction)
  • Unit 4: 558 therms vs. 401 therms (-28.1% reduction)
• Total gas consumption reduction across 4 units: -29.5% year-over-year

Property owner’s financial summary:

• Annual operating cost savings (gas): approximately $580 per unit at current Dominion rates, $2,320 total annually across 4 units
• Eliminated emergency dispatch costs: $1,840+ per year (averaged from 2023-2024 baseline)
• Combined annual benefit: approximately $4,160
• Payback on $21,600 net cost: 5.2 years
• Expected remaining service life beyond payback: 13-17 years per unit

Tenant satisfaction:

Jordan reported all four tenants expressed satisfaction with new equipment. Specific positive feedback: more consistent heat output, less noise during operation, quicker recovery from setback temperatures (programmable thermostats). One tenant (Unit 4 graduate student) specifically commented on the difference in mid-November when sub-freezing temperatures arrived — equipment maintained setpoint reliably during the first cold snap of the season.

Property occupancy and rent stability:

All four units remained occupied throughout the winter heating season. Two tenants on lease renewal in spring 2025 chose to renew (typical lease renewal rate at this property had been approximately 60%; both renewals citing reliable heating as a positive factor).

Jordan’s overall assessment:

“The coordinated replacement approach was clearly better than reactive emergency dispatches. The owner was initially hesitant about the upfront cost, but the operational simplification of having all four units on the same equipment platform — combined with the gas bill reduction — convinced him this was the right approach. We’re applying this template to another property in his portfolio.”

Ongoing service relationship:

Commercial maintenance plan active. Annual tune-ups scheduled for fall 2025 (combined two-day visit covering all four units). Jordan continues coordinating other properties through us; expanded service relationship.

Why This Case Study Illustrates Important Patterns

Coordinated vs. reactive equipment management:

Multi-unit rental property HVAC management benefits significantly from coordinated replacement when equipment is at end of life across the portfolio. Reactive emergency dispatch is more expensive per occurrence and disrupts tenant relationships. Coordinated phased replacement standardizes equipment, simplifies future maintenance, and eliminates the unpredictable expense pattern.

Heat exchanger crack handling:

Unit 3’s confirmed heat exchanger crack identified during pre-replacement assessment elevated this unit to immediate priority. CO escape through cracked heat exchangers is a safety concern, not just an efficiency issue. Property managers handling residential rental properties should ensure annual furnace inspections include heat exchanger borescope examination on equipment over 15 years old.

Tenant communication during multi-unit installations:

Property manager Jordan handled all tenant communication, scheduling, and coordination. Our crew coordinated directly with Jordan for unit access. This division of responsibility worked well; tenants experienced minimal disruption (2-day installation per unit), and the property owner avoided the operational complexity of coordinating directly with tenants.

Equipment standardization value:

Goodman GMVM97 selected for all four units. Standardization simplifies: (a) future maintenance technician familiarity, (b) parts inventory needs, (c) tenant operation instructions, (d) warranty tracking. The slight equipment cost premium for standardization (vs. opportunistic equipment purchasing) pays back through reduced operational complexity.

Rental property tax treatment:

Federal IRA 25C tax credits don’t apply to rental properties (only personal residences). Property owners should consult their tax professionals about depreciation strategies (Section 179 expensing, bonus depreciation, MACRS schedules) for HVAC capital investments. The depreciation tax benefit can be significant but is property-owner-specific.

Code Compliance Documentation

Applicable codes for this project:

• 2024 IMC with Utah amendments: Mechanical equipment installation
• IFGC Section 304.1: Altitude derate at 4,265 ft elevation (17.1% derate)
• UMC Section 510: Combustion air provision (sealed-combustion design)
• ACCA Manual J: Heat load calculation per unit (35,400-38,800 BTU/hr range)
• ACCA Manual S: Equipment selection (60,000 BTU/hr nameplate appropriately sized)
• 2021 IECC: Energy efficiency requirements (96% AFUE significantly exceeds minimum)
• NEC 250.104(B): CSST bonding verified compliant for each unit
• Utah landlord-tenant law: 30-day advance notice provided to all tenants per Utah Code 57-22-4

Permit numbers:

• Unit 3: South Salt Lake Building Department permit #B-2024-19002
• Unit 1: South Salt Lake Building Department permit #B-2024-19847
• Unit 2: South Salt Lake Building Department permit #B-2024-20885
• Unit 4: South Salt Lake Building Department permit #B-2024-21924

All inspections passed:

Each unit’s installation inspected and approved on first review by South Salt Lake Building Department within 3 business days of installation completion.

Frequently Asked Questions

Why coordinated phased replacement instead of replacing all four units at once?

Three factors. (1) Tenant disruption minimization — replacing all four units simultaneously would require coordinating four separate tenant schedules concurrently, creating logistical complexity. (2) Cost cash flow management — spreading the $22,400 cost over 6 weeks allows property owner to handle cash flow more easily. (3) Crew efficiency — concentrating on one unit at a time allows our installation crew to focus on quality, avoiding multi-unit chaos that can lead to errors.

Why didn’t the property owner choose cost-conscious tier equipment?

Trade-off analysis. Cost-conscious tier Goodman GMVC8 80% AFUE at $4,200 per unit would have saved $5,600 total ($1,400 per unit). However: (a) 80% AFUE vs. 96% AFUE means approximately 16% higher gas operating costs annually per unit, eating into the equipment cost savings within 5-6 years; (b) 80% AFUE equipment doesn’t qualify for Dominion ThermWise rebate ($800 total project savings forfeit); (c) tenant satisfaction with reliable, efficient equipment supports occupancy stability. Net analysis showed Goodman GMVM97 96% AFUE was better value over equipment life.

What about heat pump conversion for the rental property?

Considered but not selected. Heat pump conversion would require: AC equipment addition (not present in property), electrical service upgrades on some units, smart thermostat integration. Total project cost would have approximately doubled ($45,000+ vs. $22,400). For rental property context where tenants pay utility bills (not the property owner), the operating cost savings of heat pump conversion accrue to tenants rather than owner — weakening the owner’s economic case for the higher upfront investment. Heat pump conversion makes more economic sense for owner-occupied homes than typical rental property configurations.

How did you handle tenant interaction during installations?

Property manager Jordan handled all tenant scheduling and access coordination. Our crew arrived at scheduled times, performed work, and departed. Tenants weren’t required to be present during installation (Jordan provided unit access via property management keys). Tenant communication was Jordan’s responsibility, not ours; we communicated with Jordan only. This division of responsibility worked smoothly.

Will the equipment last 20 years for rental property use?

Goodman residential furnaces have a service life typically of 18-22 years with annual maintenance. Rental property use patterns can be slightly harder on equipment (single setpoint operation vs. setback patterns of owner-occupied homes, occasional tenant misuse). With the commercial maintenance plan providing annual tune-ups, expected service life should remain in the upper range of 18-22 years. The 10-year parts warranty (transferable) covers significant initial period of operation.

Project Details Summary

Customer:

Jordan Whitmer (property manager) on behalf of out-of-state property owner

Property:

4-unit residential complex, State Street corridor South Salt Lake, single-story 1978 construction

Project:

Coordinated 4-unit furnace replacement (1978 Coleman equipment at end of life); phased over 6 weeks

Completion dates:

Unit 3: August 14-15 (priority due to heat exchanger crack); Unit 1: August 28-29; Unit 2: September 11-12; Unit 4: September 25-26, 2024

Total cost:

$22,400 installed ($5,600 per unit), $21,600 net after Dominion ThermWise rebates

Equipment installed:

Goodman GMVM970603BN 96% AFUE modulating furnaces (60,000 BTU/hr each, altitude-derated for 17.1% reduction), Honeywell T6 Pro programmable thermostats, MERV 8 filter housings, PVC concentric venting

Outcome:

29.5% gas consumption reduction across 4 units winter 2024-2025 vs. 2023-2024. Zero emergency dispatches winter 2024-2025 (vs. 3 emergency dispatches previous winter). 5.2-year payback period combining operating cost savings and eliminated emergency dispatch costs. Tenant satisfaction strong; lease renewal rate stable.

Ongoing service relationship:

Commercial maintenance plan active for all 4 units ($480/year per unit, $1,920/year total). Jordan continues coordinating expanded portfolio through us.

Schedule Multi-Unit Property Consultation

• Phone: (385) 300-1867
• Address: 756 E Winchester St #322, Salt Lake City, UT 84107
• Email: info@saltlakecityheatingairconditioning.xyz
• Utah DOPL HVAC Contractor License: #11567823-5501
• EPA Section 608 Universal (Lead Tech): #608U-2009-447129

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