Smart thermostat installation and setup in Scarborough, Durham and the GTA
A smart thermostat is a control, not an upgrade to your heating system. Fitted to the right equipment and configured for it, it will run that equipment more sensibly than a manual dial. Fitted to the wrong equipment, or left on its defaults, it will run it worse. The difference is almost entirely in the wiring and the configuration. Metropolitan Heating and Air Conditioning has been installing and configuring controls on all makes and models across Scarborough, Durham Region and the GTA since 1979.
Call (416) 283-5698, Monday to Friday 8:00 AM to 4:00 PM.
The C-wire is the first question
An old mechanical or battery thermostat only had to close a switch. A smart thermostat runs a display, a radio and a processor continuously, and that needs a constant 24-volt supply. The common wire — the C-wire — is the return path that provides it.
Plenty of houses have a thermostat cable with a spare conductor sitting unused behind the plate, and then it is a matter of landing it at both ends. Plenty of others have a four-conductor cable with nothing to spare. The options then are running new cable, which is clean but means getting from the thermostat location back to the furnace, or fitting a power-extender module at the furnace board, which multiplexes the supply onto the existing conductors.
Thermostats that advertise no C-wire requirement generally run off a trickle drawn through the heating or cooling call. That works on some systems and causes intermittent false calls or short cycling on others, particularly with electronic ignition boards. It is worth knowing which situation you are in before the thermostat is on the wall.
A heat pump needs a thermostat that understands it
This is the mismatch we see most. A heat pump is not a furnace with extra terminals. It needs a reversing valve output — O or B depending on the manufacturer, and getting that backwards means the system heats when you ask for cooling. It needs auxiliary and emergency heat handled as separate stages. And it needs balance-point logic: the temperature below which the electric or gas backup is allowed to help, and the rules for when the compressor alone should keep running instead.
A thermostat that simply energises the backup whenever the room is a degree behind the setpoint will run expensive resistance heat far more than it needs to. Configuring the changeover properly is most of the value in fitting a heat-pump-capable control. If you are considering the equipment as well, start at heat pumps.
Staging, and what the thermostat has to know about your furnace
A two-stage furnace runs a low fire that covers most of the season and a high fire for cold snaps. A variable-speed or modulating furnace adjusts continuously. Either way the control has to be told what it is driving.
Set up as single-stage, a two-stage furnace will often be driven straight to high fire on every call — shorter, harder cycles, more temperature swing and more noise, from equipment that was bought specifically to avoid that. Configured correctly, it spends most of the winter on low fire with longer, gentler cycles and steadier room temperatures. The same applies to the blower: a variable-speed motor set as fixed-speed loses the low-speed circulation that evens out the house between calls.
What scheduling and setback actually do
Setback saves energy for a simple reason: a house loses heat in proportion to the difference between inside and outside, so a cooler house loses less. The saving comes from the hours spent at the lower temperature, not from the thermostat being clever.
Two caveats worth knowing. Recovery from a deep setback on a heat pump can bring on backup heat and cost more than the setback saved, which is why heat-pump-capable thermostats use gradual or adaptive recovery. And geofencing, remote sensors and occupancy detection are only as good as their configuration — a remote sensor left averaging with a hallway sensor will control to a temperature nobody is sitting in.
Installation and configuration
Power is isolated at the furnace, the existing wiring identified and documented before anything is disconnected, and the new control mounted — away from supply registers, direct sun and exterior walls, all of which make it read a temperature the house is not at. Equipment type, stages, changeover, backup heat and cycle rates are then set on the thermostat, the system is connected to your network, and every mode is run through to confirm the right output energises. Then we sit down and show you how the schedule works, because a thermostat left on its factory schedule is the commonest reason people conclude it did nothing.
Book it
Call (416) 283-5698 weekdays 8:00 AM to 4:00 PM, or tell us the make of your furnace. See also smart HVAC, heating and whole-home HVAC. Licensed and insured, in Scarborough since 1979.