Furnace Installation in Fullerton — Done Right, Done Safely
A new furnace is a 15+ year decision with real safety implications. We install high-efficiency gas furnaces properly — correct sizing, proper venting, safe combustion — and we’ll honestly compare a gas furnace to a heat pump alternative if you want to weigh both options.
If your gas furnace is at the end of its life — typically 15–20 years old, with rising repair costs and falling efficiency — you’ve got a decision to make. Replace with another gas furnace, or switch to an electric heat pump. We install both, and we’ll lay out the real trade-offs for your specific home so you can choose with full information.
If you’ve already decided on a gas furnace replacement, this page covers what we do, how we do it, and what rebates and financing are available. If you want to compare gas vs. heat pump first, we’ll come do an estimate that quotes both.
When It’s Time to Replace Your Furnace
Most gas furnaces last 15–20 years in Southern California’s mild climate. Here are the common signals that replacement is the better call than another round of repairs.
- Age: 15+ years. Older furnaces become increasingly inefficient and increasingly expensive to repair. Modern 95%+ AFUE furnaces are dramatically more efficient than older 70-80% AFUE models.
- Cracked heat exchanger. Non-negotiable replacement signal. A cracked heat exchanger lets combustion gases (including carbon monoxide) into the air you breathe. On older systems, full replacement is typically the safer and more economical call than heat exchanger replacement.
- Multiple repairs in the past 1–2 years. Throwing $500–$1,200 at an aging furnace repeatedly is usually more expensive than financing a new high-efficiency system that qualifies for rebates.
- Pilot-light system on a 20+ year old furnace. Standing pilot light technology is decades behind modern electronic ignition. Less efficient, less reliable.
- Energy bills climbing. System efficiency degrades over time. An old 70% AFUE furnace wastes 30 cents of every gas dollar on combustion losses; a new 95%+ AFUE furnace wastes only 5 cents.
- Hot and cold spots in your home. Original system may have been wrong-sized. Replacement is your chance to get it right.
The Honest Question: Gas Furnace or Heat Pump?
When your furnace fails, you’re not just deciding which brand of furnace to buy — you’re deciding whether to stay with gas heating at all. We owe you a straight answer on both options. Here’s the short version.
🔥 Stay with a Gas Furnace if…
- You’re attached to gas heat and want familiar reliability
- Your existing AC is relatively new (under 8 years) and working well
- You prefer faster warm-up times on the rare cold mornings
- Up-front budget is the most important constraint and your existing gas line is sized correctly
- You want to qualify for SoCalGas’s 95%+ AFUE rebates without changing systems
♻️ Consider a Heat Pump Instead if…
- Your AC is also aging (12+ years) and would need replacement soon anyway
- You want the higher rebate dollars ($1,000–$2,000+ from SCE)
- You’re open to all-electric and want to avoid future gas system investments
- Lower long-term operating costs matter more than up-front simplicity
- Single-system maintenance appeals to you (one system to maintain instead of two)
Either way, we’ll quote what you ask for — and we’ll always tell you when one option has a clear advantage for your specific situation. See heat pump installation details →
How We Install Gas Furnaces
Furnace installation done right involves more than just dropping in a new unit. It involves proper sizing, proper combustion air, proper venting, and safety verification. Here’s what’s included.
Manual J Sizing
Heat load calculation for your specific home — not “what size was the old one.” Right-sized furnaces are more efficient and longer-lived.
High-Efficiency Equipment
95%+ AFUE furnaces qualify for SoCalGas rebates and waste minimal gas in combustion losses. Lower-efficiency 80% AFUE available if budget-constrained.
Proper Venting
High-efficiency furnaces use PVC venting (not metal) because their exhaust runs cool enough. We size, route, and seal venting per manufacturer specs.
Combustion Air Verification
Gas furnaces need adequate combustion air. We verify and adjust based on the installation location (garage, closet, basement, attic).
Permit & Inspection
We pull the city permit and coordinate the inspection. Required for code compliance and necessary for SoCalGas rebate eligibility.
CO Detector Verification
California requires working CO detectors near sleeping areas. We verify yours are present and functional — install new ones if needed.
Removal & Disposal
Old furnace removed and properly disposed. Gas line capped or transitioned safely. Old electrical disconnected.
Thermostat Setup
Compatible thermostat included with most installs. We program it correctly and walk you through the controls.
Warranty Registration
Manufacturer warranty registered for you. Most installations include 10-year parts warranty.
Our Installation Process
From your first call to a running furnace, here’s how a typical installation unfolds. Most furnace replacements from quote to running system take 2–3 weeks.
Free Estimate
In-home assessment, load calculation, written quote with options.
Equipment Selection
Choose efficiency level (80% or 95%+ AFUE), brand, and features.
Rebates & Financing
Identify applicable rebates, walk through financing options.
Installation Day
Old furnace removed, new system installed, vented, tested, commissioned.
Walkthrough & Warranty
System demo, thermostat setup, warranty registration, safety check.
Current Rebates & Incentives for Gas Furnaces
High-efficiency gas furnaces qualify for several California incentives. Lower-efficiency 80% AFUE furnaces generally don’t qualify — which is part of the cost-benefit math when choosing between efficiency tiers.
SoCalGas Home Energy Efficiency Rebate
Rebates available for ENERGY STAR certified central natural gas furnaces (95%+ AFUE typical threshold). Active through December 31, 2026. Specific rebate amount confirmed during estimate.
Manufacturer Rebates
Seasonal promotional rebates from major manufacturers on qualifying installations. We track current offers and pass them through to you.
GoGreen Home Energy Financing
California state-administered low-interest financing for energy-efficient HVAC upgrades. Often beats standard lender rates for qualified applicants.
Rebate amounts and program availability change throughout the year. We verify what’s currently active for your specific project during your free estimate. See our financing & rebates page for full details.
Furnace Brands We Install in Fullerton
We install most major residential furnace brands. We don’t push you toward whichever brand has the best margin for us — we recommend the brand and model that best matches your home, budget, and efficiency goals:
We also install furnaces from York, American Standard, Amana, Ruud, Coleman, and other major residential brands. If you’re considering a specific brand or want a side-by-side comparison between options, just ask — we’ll walk you through trade-offs in efficiency, reliability, features, and warranty so you can make an informed choice.
💰 Financing & Rebates Available
A new gas furnace installation is typically $4,500–$9,000+ depending on system size, efficiency level, and any duct, electrical, or venting work needed. After SoCalGas rebates and financing, the project becomes much more manageable.
Available: $0-down financing, same-as-cash promotional periods, low-monthly long-term plans, SoCalGas Home Energy Efficiency Rebate, manufacturer rebates, and California’s GoGreen Home Energy Financing. See full financing & rebates details →
📍 Furnace Installation Service Area
We install gas furnaces throughout North Orange County and Southeast LA County — including Fullerton, Brea, La Habra, La Mirada, Whittier, Anaheim, Yorba Linda, Buena Park, Placentia, Hacienda Heights, Rowland Heights, Cypress, La Palma, and surrounding communities. Not sure if you’re in our area? Call us — we’ll let you know on the spot.
Furnace Installation FAQ
How much does a new furnace installation cost in Fullerton?
Total cost typically ranges from $4,500 to $9,000+ depending on furnace size, efficiency level (80% AFUE on the lower end, 95%+ AFUE on the higher end), and any required venting, electrical, or ductwork upgrades. After SoCalGas rebates on high-efficiency models and manufacturer rebates, the effective cost is often significantly lower. Free in-home estimates include a written quote with all costs spelled out.
What does AFUE mean and what AFUE should I get?
AFUE (Annual Fuel Utilization Efficiency) measures what percentage of the fuel a furnace consumes is actually converted to usable heat. An 80% AFUE furnace turns 80% of the fuel into heat; the other 20% goes out the exhaust. A 95% AFUE furnace turns 95% of the fuel into heat — much less waste. Higher AFUE costs more up front but uses significantly less gas over its lifetime. SoCalGas rebates typically require 95%+ AFUE. For Fullerton’s climate, the payback math usually favors high-efficiency.
How long does furnace installation take?
Standard residential furnace replacement takes 4–8 hours of work on site, typically completed in a single day. If we’re also replacing the AC at the same time, upgrading ductwork, or running new venting, it can extend to 1–2 days. The total time from quote to completion is typically 2–3 weeks depending on equipment availability and scheduling.
What size furnace do I need?
The right answer comes from a Manual J load calculation, not from “what size was there before.” Furnaces are sized in BTUs (British Thermal Units). Oversized furnaces short-cycle, are less efficient, and produce uncomfortable temperature swings. Undersized furnaces run constantly and never adequately heat the space. We calculate the right size for your specific home based on square footage, insulation, window orientation, ceiling height, and other factors.
Should I replace my AC at the same time?
Worth considering. If your AC is also aging (12+ years), replacing both at the same time saves significant labor cost compared to two separate installations. It’s also the natural decision point for considering a heat pump alternative. If your AC is relatively new and working well, no — keep it. We’ll give you a clear assessment as part of the furnace estimate.
What about the venting — does that need to change?
Depends on the new system. Standard-efficiency (80% AFUE) furnaces use traditional metal venting that often matches what you already have. High-efficiency (95%+ AFUE) furnaces produce cooler exhaust that requires PVC venting — typically running to an exterior wall or roof. New PVC venting is part of the installation cost on high-efficiency installs.
Do you handle the permit and inspection?
Yes. Furnace installations in California require a city permit and an inspection. We pull the permit, schedule the inspection, and handle the entire process. Beware of contractors who suggest skipping the permit “to save money” — unpermitted gas work creates safety, insurance, and resale problems.
What’s the warranty?
Most major manufacturers offer 10-year parts warranties on registered residential furnaces. Heat exchanger warranties are often 20 years or lifetime. Labor warranties vary — we offer a standard labor warranty on our installations, and extended labor warranty options are available. Specific warranty terms are confirmed in writing with your quote.
Ready for a Properly Installed Furnace?
Schedule a free in-home estimate. We’ll measure, calculate, walk through your options (including a heat pump comparison if you want one), and quote in writing — with no pressure and no surprises.