Furnace replacement in Algonquin, Illinois
A new furnace sized to your house, not guessed at, and installed with the permit your town requires. If yours is worth repairing instead, we will tell you.
Serving Algonquin, Crystal Lake, St. Charles, Geneva and Vernon Hills.
Signs your furnace is due for replacement
- It’s old, and every winter starts with a repair call
- Some rooms never get warm while others run hot
- The heating bills keep climbing
- A technician has told you the heat exchanger is cracked
- You’re finishing the basement and wonder whether the furnace can keep up
What’s included
Licensing for heating and cooling is set town by town in Illinois. The subcontractor who installs your furnace holds what your town requires and is insured.
Sizing to your house
Worked out for your house, not copied from the old furnace’s label. Bigger isn’t automatically better.
Removing the old furnace
Disconnected and taken away.
Installing the new one
Connected to your ductwork and thermostat, started up and checked.
The permit
Replacing a furnace needs a permit in Algonquin, Crystal Lake, Geneva and Vernon Hills. It’s part of the job.
Rebates, checked
Nicor Gas rebates on high-efficiency furnaces installed in 2026, confirmed when we price your job.
How it works
- 1
We look at what you have
The furnace’s size and age, the ductwork it feeds and how the house heats now.
- 2
Repair or replace, honestly
If a repair makes more sense, we tell you. If it’s time to replace, we say why.
- 3
A written estimate
The furnace we would install and why that size, what it costs, the permit and any rebate it qualifies for.
- 4
Installation
The old furnace comes out, the new one goes in, and it is started up and checked.
How it’s priced
We price a furnace after we’ve seen the house. The size and efficiency of the furnace, and how much the ductwork or venting needs changing, move the price most.
Nicor Gas offers a rebate on a high-efficiency furnace installed in 2026, larger with a qualifying smart thermostat. Apply within 90 days of installation, and by January 31, 2027 at the latest. Your estimate lists any rebate your furnace qualifies for.
The federal tax credit for efficient furnaces ended with equipment installed in 2025. It doesn’t apply this year.
What moves the price
- The size and efficiency of the furnace
- Whether the ductwork or venting needs changes
- Replacing the air conditioner at the same time, or not
- Heat for a finished basement, if you’re adding one
You get a written, itemized estimate after we’ve looked, and nothing starts until you’ve signed it.
Why us for this job
Sized to the house
The size is worked out for your house, not guessed at or copied from the old unit, and you can ask what it was based on.
Straight about repair
If your furnace is worth repairing, we will say so, even though it means no replacement job for us.
Planned with the basement
The furnace sits in the basement. If you’re finishing it, the new furnace is sized for the house as it will be, finished basement included.
Questions about furnace replacement
Is there still a federal tax credit for a new furnace?
No. The federal energy-efficient home improvement credit covered equipment installed through the end of 2025. Nicor Gas furnace rebates still apply in 2026.
Do I need a permit to replace a furnace?
Yes in Algonquin, Crystal Lake, Geneva and Vernon Hills, and we check your town’s rules before we price the job. The permit is part of the job.
What size furnace do I need?
It depends on the house: its size, insulation, windows and layout, not the size of the old furnace. We work it out and write it on the estimate.
Should I replace the furnace and air conditioner together?
Not always. If both are old, doing them together means one installation and a matched pair. If the air conditioner has years left, it can stay, and we will tell you which makes sense for yours.
My furnace just stopped. Can you come today?
We plan and install replacements; we don’t offer same-day repair visits. If you have no heat now, a repair company is the fastest way to get it back. If the furnace turns out to be near the end of its life, we can price the replacement.
Related services
Air conditioning
Central air installed or replaced, matched to your ductwork where it can be.
Basement heating and cooling
Ducts carried into a finished basement, or a zone of its own.
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A cold basement, or a furnace on its way out?
Tell us what you have and what it’s doing. We’ll look at the system and give you a written estimate.
Someone from our team calls or texts to set up a visit.