Digital thermostat mounted on a concrete wall

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Thermostat cycle rate (CPH) settings: matching the setting to the heating and cooling equipment

Many Honeywell/Resideo and similar digital thermostats use a cycle-rate setting (cycles per hour, CPH) instead of an adjustable heat anticipator. The number tells the thermostat how often it is allowed to cycle the equipment at about a 50% load. A setting meant for an electric furnace on a steam boiler gives short, inefficient firing; a steam setting on a forced-air furnace gives big temperature swings. Check the system type, then set heat, auxiliary/emergency and compressor cycle rates to match the equipment. This is a settings job: no wiring changes and no gas work.

Single source ~15 min easyBrands: Honeywell Home / Resideo, All

Before you start

Settings only. Do not jumper terminals at the furnace or boiler board to 'test' cycling.
Cycle-rate changes do not bypass the compressor's minimum off-time protection; leave that protection on (typically 5 minutes) so the compressor is not restarted against high pressure.
Steam and hot-water boilers have their own limit and low-water controls. If a boiler is short cycling on its limit, the cycle rate is not the cause; refer limit, pressure or gas-side problems to a licensed heating tech.

Diagnostic steps

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