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Hot summers, cheap tract ductwork, and forty years of guessing at sizes
Central Contra Costa runs a long way hotter than the coast, the housing here was built quickly, and almost none of it has had a load calculation done on it since. Those three facts explain most of what we are called out to.
The calls we take most
No cooling in a heat spell
The week everybody calls. Diagnosed and priced before anything is fitted, with the repair figure given separately from any replacement figure so you can compare them yourself rather than take one number.
Upstairs will not cool
Before anybody prices equipment: airflow at the upstairs registers against the downstairs ones, static pressure, return capacity and the state of the attic runs. Crushed and disconnected flex duct is the commonest finding in this housing stock and it costs a fraction of a system.
Cool but clammy
The classic oversizing symptom. A system that satisfies the thermostat quickly never runs long enough to remove moisture, so the house is cold and damp at once. The answer is rarely more capacity and is frequently less.
No heat, or a damp cold house in winter
Furnaces and heat pumps, combustion tested and heat exchangers inspected on anything that burns gas. Winter complaints here are as often about ventilation and moisture as about heat output.
A second opinion on a quote
You have been told the system needs replacing, or that you need a bigger one. We measure it and tell you what we find, including when the other contractor was right — which happens and which we say.
Before you buy, sell or let
What is installed, how old each unit is from its serial number, what condition it is in and what putting it right would realistically cost. In writing, quickly.
What a load calculation actually looks at, and why it matters here
It is not a formula based on square feet, and any figure produced from square feet alone is a guess dressed up as a specification. A proper calculation is done room by room, and it looks at the glass area and which way it faces, the insulation in the walls and the attic, how leaky the building is, what shading exists, how many people are in each room and what equipment is in it, and what the ductwork can actually deliver.
Why it matters more in Concord than on the other side of the hills: the design temperature here is a long way above the coastal one, so the temptation to round up is strong, and rounding up on top of an already generous calculation is how houses end up with systems half again as large as they need.
What it produces: a number per room and a total, with the assumptions written down. If the assumptions are wrong — if you are about to replace the windows, or add insulation, or convert the garage — tell us, because the answer changes and it is far cheaper to change it before the equipment is ordered.
Four things we say to homeowners here
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Bigger is not safer
An oversized system cools the air without drying it, short-cycles, wears its compressor out early and costs more to run. The only thing it does better is satisfy a thermostat quickly, which is the one thing that does not matter.
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The ducts decide what is possible
A system can only deliver what the ductwork carries. Measuring static pressure and airflow takes an afternoon and it determines which options are genuinely available to you.
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Ask for the repair price on its own
Repair and replacement should be two numbers on the same visit. A quote that carries only the larger figure has made the decision on your behalf.
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A gas appliance with no carbon monoxide alarm is the one urgent item
Everything else on this page can wait for a convenient week. That cannot. Fit one, and have the combustion tested and the heat exchanger inspected.