Residential heating and cooling across the south Chicago suburbs. Three crews on rotation, two on shift overnight through the heating season. No answering service, no page-back, no guessing whether help is coming.
Gas, electric, and oil. Same-day diagnosis, parts on the truck for common failures, most no-heat calls resolve in one visit.
High efficiency gas, hybrid heat pump, and full system swap-outs. Carrier, Lennox, Rheem, Goodman. Financing through Synchrony.
R-410A and R-32 certified. Summer slot availability down to the same day. Real diagnosis, not a lazy recharge.
Split systems, mini-splits, and matched coils. We size by Manual J, not by eyeballing the old nameplate.
Twice a year visits keep warranties intact. Priority scheduling for members.
Whole-home humidification, UV filtration, and air balance. What actually matters after a winter of burning furnaces.
Not an answering service that pages you back. Real techs, real trucks, real parts, on shift overnight through heating season.
Mark Sullivan started Shift Heating and Cooling in 2014 after ten years running service for a big south-side shop. Same crew on the trucks since year one.
Licensed Illinois contractor, bonded, and insured. NATE certified, EPA 608 Universal across every tech.
Every install and every major repair carries a one-year labor warranty. We come back and fix it at no charge.
"Furnace died at 1am on a Tuesday in January with the baby's room at 54 degrees. Called Shift, they had a crew at my door by 2:30, ignitor replaced and heat back on before 4. That's not normal."
Thanks for trusting us with the late night call, Mike. Glad the heat's back on and the house was warming up by the time we left.
"Got three quotes for a full system swap. Shift wasn't the cheapest but they were the only ones who actually measured the house before quoting. Install took two days, zero mess, and the AC finally cools the upstairs like it's supposed to."
Manual J exists for a reason. Glad the second floor is fixed, Sarah. Twelve years of install work and I've never seen a system sized right without the math.
"Older boiler in our Mokena bungalow started banging last fall. Shift diagnosed a dead circulator, had the part the next morning, back up by noon. Price was what they quoted on the phone. No surprises."
Quoted price is the paid price around here, Dave. Glad the boiler's quiet again.
"Tune-up appointment, the tech showed up on time in a marked truck, walked me through the whole system, showed me what was coming and what wasn't, and didn't try to sell me anything I didn't need. That's rare."
Appreciate the note, Lisa. The job on a tune-up is to tell you what's true, not to pad a ticket.
AI drafts the reply. Mark approves before it goes live.
Rusted 20-year-old Carrier swapped for a 96 percent AFUE Lennox with smart thermostat. Full house rebalance after the install.
Old condenser and line-set replaced with a 16 SEER2 Rheem. The second floor cooled properly for the first time in years.
Cast-iron boiler at end of life replaced with a wall-mounted Weil-McLain combi unit. Radiator pressure reset, full bleed.
Added a 3-ton Carrier hybrid heat pump to an existing gas furnace setup. Homeowner saw a 30 percent winter bill reduction.
Three-zone ductless mini-split in an older garage conversion. No ductwork, no drywall cuts, full heating and cooling.
Whole-home bypass humidifier added to an existing furnace. Goodbye nosebleed winters.
Dispatch log pulled from the crew scheduler. AI tightens the write-ups.
Mark Sullivan grew up in Tinley Park, did his HVAC apprenticeship in Harvey in the late nineties, and ran residential service for a big south-side shop for ten years before starting Shift in 2014. The shop is built around one idea. If you pick up the phone at 2am, you also need to know what you're doing at 2am. Three crews on rotation, two on shift overnight through heating season. No answering service, no page-back, no guessing whether help is coming.
Coil clean, refrigerant check, capacitor test, and a full system report with photos. One unit, single family home.
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