York service in San Mateo County

York furnace or AC? We repair and replace them.

York furnaces, air conditioners, heat pumps and package units, at homes and small commercial buildings in San Mateo and Santa Clara counties. Here is what goes wrong with them and what we do about it.

CSLB license#1155755

Which York systems do you work on?

York gas furnaces, central air conditioners, heat pumps, air handlers and package units.

We repair and maintain them, and when one is past fixing we replace it with a new furnace, or a heat pump if you're thinking of going electric, and talk through what goes in.

Common York problems, and what we do

What owners notice, what it usually means, and how we handle it. If it smells of gas, leave the house and call your gas utility from outside.

What you noticeWhat it usually meansWhat we do
The furnace starts, shuts off and won't relightA safety switch is stopping it: often a blocked vent or condensate drain, a dirty flame sensor or an overheating limit.We read the furnace's status light, find the switch that tripped and why, and fix the cause instead of resetting it.
A light blinking inside the furnace doorThe control board is reporting a fault. The code chart for your model is usually printed on the inside of the door.Count the blinks and tell us when you call. It tells us what to look at first.
The AC runs but the air isn't coldLow refrigerant from a leak, a dirty coil, or a failed capacitor or fan motor at the outdoor unit.We test before we add anything, and fix a leak before we recharge.
Ice on the refrigerant lines or the indoor coilToo little air over the coil (a clogged filter or a weak blower) or low refrigerant.Switch the cooling off so it thaws, then call. We find out why it froze.
Water around the furnace or air handlerA blocked condensate drain, a failed condensate pump or a tripped float switch.We clear and flush the drain, test the switch and replace a failed pump.
Steam from the outdoor heat pump on a cold morningUsually the defrost cycle, which melts frost off the outdoor coil. Heat stops for a few minutes, then comes back.Nothing, if it clears and the heat returns. Call if it keeps icing up.

Is your York system down?

Call, or book a visit online. Have the model number from the label ready if you can.

What to check before you call

A few things worth a minute before you book. If none of them fixes it, call.

  • The thermostat or remote is on the right mode (Cool or Heat, not Fan) and set past the room temperature.
  • The breaker for the system is on, and so is the switch beside the outdoor unit.
  • The filter is clean. A clogged one can stop the cooling and freeze the coil.
  • The outdoor unit is clear of leaves, plants and anything stacked against it.
  • The model and serial number label is photographed: it is on the side of the outdoor unit and inside the furnace or air handler door.

Should I register my York system?

York's terms and how to register are in the papers that came with the system and on York's website. If your system is new, look for the registration terms now; we can find the model and serial numbers for you.

Can you work on a York system someone else installed?

Yes. Who put it in doesn't matter for a repair. We work from the model and serial number on the label.

Who will be working on my system?

AD Mechanical Services Inc., owned by Adlan Cherkesbiev, under CSLB license #1155755, C-20 Warm-Air Heating, Ventilating and Air-Conditioning. We aren't connected with York; we're the local contractor who works on it.

Tell us what it's doing. We'll take it from there.

Call and describe the problem: the noise, the smell, the room that never warms up. Or book a visit online.

A heat pump outdoor unit with its service panel off beside a San Mateo home

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