Compare HVAC quotes on what happens under the house

A heat pump sized from the old nameplate inherits whatever mistake was made the last time, and here the mistake usually runs large: a system that cools the house in twenty minutes and shuts off before it has pulled any moisture out of the air. A room-by-room calculation is an hour of work and the only line that decides whether the house feels dry in August.

Model numbers name the efficiency, the compressor type and the cold-weather capacity; a phrase like sixteen SEER heat pump names none of them. On a January night in the Bluegrass the difference between a standard unit and a cold-climate one is whether the strip heat comes on at all.

In most houses here the ducts run through the crawl space, and a duct that leaks a fifth of its air into a damp crawl space wastes a fifth of the new system before it reaches a register. Sealing, insulating and testing them is a separate line, and the one most often absent from the lower quote.

Reusing the old copper is quicker on the day, and it is the usual reason a new heat pump loses its charge in its second summer. Whether the line set is replaced or flushed and pressure-tested, and to what length, belongs in the number.

A modern heat pump with auxiliary heat can need a larger breaker and a new disconnect, and on the older housing stock around Lexington sometimes a panel upgrade. Whether the electrician is in the quote or in a phone call afterward is the difference between two quotes that look the same.

An air handler in a crawl space or a closet drains somewhere, and in this humidity it drains all summer. A float switch that shuts the system down before the pan overflows costs a few dollars and is easy to leave off; a ceiling replaced after a clogged line is not.

When the outdoor temperature drops below the heat pump's useful range, something else heats the house, and here that happens several nights each winter. Strip heat, a gas furnace kept as backup, or a cold-climate unit that rarely needs either are three different electric bills. The quote should say which.

A heat pump installed and switched on is not a heat pump installed correctly. Refrigerant charge, airflow across the coil and static pressure through those crawl-space ducts are measured, or they are guessed. Ask for the start-up sheet.

Lexington and the surrounding counties each inspect on their own schedule. Included, billed separately, or left to the owner are three different deals, and only one puts a licensed contractor's name on the file the next buyer will ask about.

The old unit and its refrigerant leave the property somehow, and the refrigerant is recovered by someone certified to do it, or it is not. A line that says haul away included is the honest version of a line that says nothing.

The manufacturer covers the compressor and the parts, usually only if the unit is registered within a window the homeowner rarely knows about. The contractor covers the labor, which is what fails first. Who registers the unit and how long the labor is covered are worth two sentences in writing.

A heat pump run by a thermostat meant for a furnace calls the strip heat far more often than it should, and the first winter bill shows it. Whether the quote includes a thermostat that understands staging and auxiliary heat, and who configures it, is a small line with a large consequence.