Honeywell Home THM5421R02 and THX9421R5021WW Thermostat and 2-wire Adapter

hvacman0408
(86)
PrivateRegistered as a private seller
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US $110.00
Approximately£83.11
or Best Offer
Condition:
Used
“Excellent working condition! Mint.”
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Postage:
US $9.06 (approx £6.85) USPS Ground Advantage®.
Located in: Lincoln University, Pennsylvania, United States
Delivery:
Estimated between Thu, 4 Dec and Mon, 8 Dec to 94104
Estimated delivery dates - opens in a new window or tab reflect seller's dispatch time, origin postcode, destination postcode and time of order receipt, and will depend on the delivery service selected and receipt of cleared paymentcleared payment - opens in a new window or tab. Delivery times may vary, especially during peak periods, and are an estimate only.
Returns:
No returns accepted.
Payments:
    Diners Club

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eBay item number:135892912474
Last updated on 21 Nov, 2025 13:38:37 GMTView all revisionsView all revisions

Item specifics

Condition
Used
An item that has been previously used. The item may have some signs of cosmetic wear, but is fully operational and functions as intended. This item may be a floor model or an item that has been returned to the seller after a period of use. See the seller’s listing for full details and description of any imperfections. See all condition definitionsopens in a new window or tab
Seller notes
“Excellent working condition! Mint.”
Power Source
Battery
Color
White
Items Included
Thermostat, Interface Module
Wire Configuration
2-Wire
Material
Plastic
MPN
YTHX9421R5127WW
Battery Size
3V Button Cell
Compatible Product
Universal
Mounting
Wall-Mounted
Brand
Honeywell
Thermostat Shape
Rectangular
Voltage Type
Low Voltage
Sensor Technology
Temperature
Number of Periods per Programmable Day
7
Control Style
Remote Control, App Control, Digital, Touch
Voltage
24 V
Model
Honeywell THX9421R
Features
Digital Display
Cool Stages
2
Programmability
Programmable
Category

Item description from the seller

About this seller

hvacman0408

100% positive Feedback•393 items sold

Joined Feb 2015
Registered as a private sellerThereby, consumer rights stemming from EU consumer protection law do not apply. eBay buyer protection still applies to most purchases.
Seller's other itemsContact

Seller Feedback (74)

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Product ratings and reviews

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5.0
11 product ratings
  • 11 users rated this 5 out of 5 stars
  • 0 users rated this 4 out of 5 stars
  • 0 users rated this 3 out of 5 stars
  • 0 users rated this 2 out of 5 stars
  • 0 users rated this 1 out of 5 stars

Would recommend

Good value

Good quality

Most relevant reviews

See all 9 reviews
  • by zonppzufquq@deleted
    29 Apr, 2020

    Full of features.

    Very nice internet gateway thermostat am able to control and set by remote computer and able to check and set by mobile smart phone. You will need a licences installer as it is very complicated to install. Yes I would buy this thermostat again and would recommend to others that would need this option.

    Verified purchase: YesCondition: NewSold by: worldsbestdeals

  • by pooldw
    15 Jun, 2017

    A very good Stat

    I use this stat all the time now (for installations) unless my customers don't want to pay for it (rare). It monitors system conditions and keeps minor problems from getting worse by notifying the customer if something goes wrong. It's a little pricey for regular replacements but when you're changing out equipment it's great.

    Verified purchase: YesCondition: NewSold by: stuff2sellthree

  • by jodieshops
    05 Jan, 2019

    Great 2-wire smart thermostat.

    The product was brand new and works perfectly. Thank you so much!

    Verified purchase: YesCondition: NewSold by: acsuperstar

  • by keepryzen
    26 Jul, 2017

    Better than nest

    I've had nest and wanted to try Honeywell!!!Works better than nest. Looks better too.

    Verified purchase: YesCondition: Pre-owned

  • by zerbi_ke
    23 Jul, 2016

    Thermostat just what I needed

    Works well and gives me the whole house control I needed. Extra value and bonu as this package came with the Internet gateway included. Love the remote access it gives. Installation very straight forward.

    Verified purchase: YesCondition: NewSold by: heating-coolingparts

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