When the propane truck comes twice in one winter, the furnace is telling you something

The second propane delivery

Propane is sold by the gallon and delivered by the truck, which makes it the most honest meter in Clay County. A Middleburg or Keystone Heights household with a propane furnace knows roughly how many fills a winter takes. When the truck comes a second time in a winter that only needed one before, the house hasn’t changed and the weather probably hasn’t. The furnace has.

The same signal shows up differently elsewhere. In Green Cove Springs, where TECO Peoples Gas reaches the spa-era streets and some newer subdivisions, it’s a gas bill that climbed. In the block ranches of Bellair and Ridgewood with electric furnaces, it’s a Clay Electric or JEA bill for January that rivals August. In all three cases the fuel is going somewhere other than into the house, and the usual reasons are mundane: a burner that isn’t burning cleanly, a blower that can’t move the air across the exchanger, a filter nobody has seen since March, a duct that let go in the attic. Every one of them is a maintenance finding, and all of them cost less to find in October than to discover by the bill in February.

Service it, fix it or retire it: the furnace tree

The inspection ends with the furnace in one of three places. Here is how we decide, out loud, with the homeowner standing there.

1. Is the heat exchanger sound? Camera and combustion numbers. If it’s cracked on a gas or propane furnace, the tree ends immediately at retire. No exceptions, no patches.
2. How old is it? Gas and propane furnaces here can reach twenty years because they work so little, but the flood-exposed ones near Black Creek and Doctors Inlet age faster from the inside. Oil furnaces with original tanks are on borrowed time regardless of how they burn.
3. What did the combustion say? Clean numbers and a good flame: service and go. Marginal numbers that clear up after cleaning the burners: service, note it. Numbers that won’t come right: a repair, and a question about why.
4. What does the fuel bill say? A steady climb over three winters means efficiency has been leaving the furnace the whole time, and a repair brings it back only to last year.
5. Should this house have a furnace at all? An electric furnace in a 1970s ranch is a strip bank and a blower, and a heat pump would cut the winter bill in half and the summer bill as well. We’ll say so even when the furnace is fine.

The service branch, which is where most October visits land, covers: burners pulled and cleaned, flame sensor and igniter checked, gas or propane pressure set to nameplate, inducer and pressure switch tested, heat exchanger scoped, flue draft verified, combustion analyzed and recorded, condensate trap cleared on high-efficiency models, blower and filter, electrical connections, limit and safety switches, carbon monoxide at the registers, and the thermostat’s heating configuration. Electric furnaces get each strip and sequencer tested under load with a clamp meter instead of the combustion steps.

Schedule a furnace inspection

Furnace brands we maintain

Cook’s installs Lennox, and a Lennox furnace gets maintained by the people who put it in. The furnaces already in Clay County closets are a broader mix: Carrier and Bryant from the 1990s and 2000s subdivisions, Rheem and Goodman from the replacement waves, Trane and American Standard, the occasional Amana or York, and propane units from manufacturers most homeowners have never heard of on rural acreage. An oil furnace in a River Road house gets the same care with a different set of tools. The checklist doesn’t change with the nameplate; only the parts on the truck do.

Warranty terms that hinge on a yearly inspection

Three things to know before the tree reaches “retire” and a new furnace is on the table:

• Heat exchanger warranties are long and conditional. Twenty years to lifetime on most modern furnaces, but the manufacturer can ask for proof of annual professional maintenance before honoring a claim. The inspection report is that proof.
• Parts warranties shrink without registration. Ten years becomes five on most equipment if nobody filed the registration in the first months. We file it on what we install, and we’ll check the status on a furnace that came with the house.
• Labor is separate. The manufacturer ships the part; the hours to install it are covered only if a labor plan was purchased with the furnace. Ask how long Cook’s furnace labor coverage runs. [[CONFIRM WITH JERRY]]

Spreading the cost when the tree ends at “retire”

A maintenance agreement puts the fall furnace inspection and the spring cooling visit on one plan, moves members to the front of the schedule and discounts any repair in between; ask how the plans are tiered and priced. [[CONFIRM WITH JERRY]] When the honest answer is a new furnace, or a heat pump in a house that never needed a furnace, the office can arrange financing on a new system, paid monthly. The utility rebates in this county go to heat pumps rather than furnaces: JEA pays its heating-and-cooling rebate at the addresses it serves, and Clay Electric offers members the Energy Smart rebate and a conservation loan. That is one more reason the “should this house have a furnace” question gets asked. The federal credits for high-efficiency heating ended for equipment placed in service after December 31, 2025, so they are not part of any number we quote.

A Penney Farms note

The retirement community and the small town around it have a higher share of residents who are home all day and sensitive to a cold house, and a higher share of older furnaces that have been “fine” for years. The inspection matters more there, not less, and the carbon monoxide reading is the line on the report we’d ask every household in Penney Farms to look at first.