Honeywell Home X2P Programmable Thermostat RTH20B (White) vs Honeywell Home X2S Smart Wi-Fi Thermostat RTH2SMC/N (White)
These are side-by-side facts taken from each product guide: published specifications, strengths and caveats as their sources state them. This page is not a test, a ranking or a verdict about which model is better.
Check Honeywell Home X2P Programmable Thermostat RTH20B (White) on AmazonCheck Honeywell Home X2S Smart Wi-Fi Thermostat RTH2SMC/N (White) on Amazon
Honeywell Home X2P Programmable Thermostat RTH20B (White)
Single-stage 1 heat/1 cool systems where Wi-Fi is not needed
A programmable thermostat that runs on two AA batteries, not included. It handles 1 heat/1 cool systems, hot water and forced air, not line voltage baseboards. The guide limits the RTH20B to a 5-2 schedule while Honeywell's spec table lists more options, and the warranty is one year limited.
Published specifications
- Maker: 1 heat/1 cool conventional or heat pump; 750 mV; hot water; forced air
- Maker and guide: powered by 2 AA alkaline batteries (not included)
- Guide: RTH20B schedule 5-2 only, 4 periods a day, or off
- Guide: heat pumps 1 compressor stage; electric backup only where backup is used
- Maker: 3.44 x 5.13 x 1.188 in; UWP wall plate; backlit LCD
- Guide and maker: 1-year limited warranty
Strengths
- Runs on AA batteries, so no C wire is described for this model
- Extended 32°F minimum heat setpoint, per guide and maker page
- Guide and maker page agree on single-stage 1 heat/1 cool compatibility
Caveats
- Schedule conflict: guide says 5-2 only; maker spec table lists 7-day too
- No Wi-Fi or remote control described for this model
- 750 mV claim appears on the maker page but not in the guide pages we read
Read the full Honeywell Home X2P Programmable Thermostat RTH20B (White) guide
Honeywell Home X2S Smart Wi-Fi Thermostat RTH2SMC/N (White)
24 VAC conventional systems up to 2H/2C, or single-stage heat pumps with electric backup
A Wi-Fi thermostat run through the First Alert app, with Matter support. It needs a C wire at 24 VAC. On heat pumps the guide allows one compressor stage and electric backup heat only. Several schedule layouts or none at all, a 32°F minimum heat option, and a 2-year limited warranty.
Published specifications
- Maker: up to 2 heat/2 cool conventional; up to 2 heat/1 cool heat pump with electric backup
- Guide: heat pumps 1 compressor stage only; gas or oil backup heat not supported
- Maker and listing: C wire required (24 VAC); Wi-Fi 2.4 or 5 GHz, 802.11 b/g/n
- Guide: schedules 1-week, 5-2, 5-1-1, 7-day or off; geofencing via First Alert app
- Maker: 3.44 x 5.13 x 1.188 in; Matter; Alexa, Google Assistant, Apple Home
- Guide, maker and listing: 2-year limited warranty
Strengths
- Guide spells out exactly which heat pump set-ups it supports
- Temperature stays adjustable at the unit if Wi-Fi drops
- Two-year limited warranty agreed by guide, maker page and listing
Caveats
- Heat pumps: one compressor stage and electric backup only, no gas or oil
- C wire required; line voltage and baseboard systems not supported
- Geofencing and remote features need the First Alert app and a connection
Read the full Honeywell Home X2S Smart Wi-Fi Thermostat RTH2SMC/N (White) guide
How to choose between them
Choose the Honeywell Home X2P Programmable Thermostat RTH20B (White) if your situation matches: Single-stage 1 heat/1 cool systems where Wi-Fi is not needed. Its main caveat: Schedule conflict: guide says 5-2 only; maker spec table lists 7-day too.
Choose the Honeywell Home X2S Smart Wi-Fi Thermostat RTH2SMC/N (White) if your situation matches: 24 VAC conventional systems up to 2H/2C, or single-stage heat pumps with electric backup. Its main caveat: Heat pumps: one compressor stage and electric backup only, no gas or oil.
Both entries repeat what each guide records. Confirm the model, included parts and availability on the current listing before ordering.
Primary sources
- Honeywell Home X2P Programmable Thermostat product page and specifications (SKU RTH20B/U) Source for Honeywell Home X2P Programmable Thermostat RTH20B (White)
- X2P Programmable Thermostat Installation and User Guide 33-00688ES-01 (listing-supplied PDF) Source for Honeywell Home X2P Programmable Thermostat RTH20B (White)
- Honeywell Home X2S Smart Thermostat product page and specifications Source for Honeywell Home X2S Smart Wi-Fi Thermostat RTH2SMC/N (White)
- X2S Smart Thermostat RTH2CWF, RTHC2CWF & RTH2SMC Installation and User Guide 33-00689EFS-06 (listing-supplied PDF) Source for Honeywell Home X2S Smart Wi-Fi Thermostat RTH2SMC/N (White)
Primary sources checked .