--- product_id: 254258171 title: "24VAC 40VA Thermostat and Doorbell Transformer, Power Supply Compatible with Nest, Ecobee, Sensi and Honeywell Thermostat, Nest Hello Ring Doorbells | Made in Vietnam" brand: "royal apex" price: "744337₫" currency: VND in_stock: true reviews_count: 8 category: "Royal Apex" url: https://www.desertcart.vn/products/254258171-24vac-40va-thermostat-and-doorbell-transformer-power-supply-compatible-nest store_origin: VN region: Vietnam --- # 40VA high power output Universal 24VAC compatibility RU-certified safety & durability 24VAC 40VA Thermostat and Doorbell Transformer, Power Supply Compatible with Nest, Ecobee, Sensi and Honeywell Thermostat, Nest Hello Ring Doorbells | Made in Vietnam **Brand:** royal apex **Price:** 744337₫ **Availability:** ✅ In Stock ## Summary > ⚡ Power your smart lifestyle with confidence and style! ## Quick Answers - **What is this?** 24VAC 40VA Thermostat and Doorbell Transformer, Power Supply Compatible with Nest, Ecobee, Sensi and Honeywell Thermostat, Nest Hello Ring Doorbells | Made in Vietnam by royal apex - **How much does it cost?** 744337₫ with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.vn](https://www.desertcart.vn/products/254258171-24vac-40va-thermostat-and-doorbell-transformer-power-supply-compatible-nest) ## Best For - royal apex enthusiasts ## Why This Product - Trusted royal apex brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Compact Yet Mighty:** Small footprint with heavyweight performance—engineered for modern smart homes craving reliability. - • **Built to Last & Protect:** RU-certified with premium copper wiring and flame-retardant materials for ultimate safety. - • **Plug & Play with Top Brands:** Compatible with Nest, Ecobee, Honeywell, Sensi, Ring, and more for effortless integration. - • **Power Your Smart Home Seamlessly:** Robust 24VAC 40VA output powers multiple thermostats & doorbells without a hitch. - • **Upgrade Your Setup, Avoid Downtime:** Replace underpowered transformers to ensure stable, reliable voltage and avoid device failures. ## Overview The Royal Apex 24VAC 40VA Transformer is a high-capacity, RU-certified power supply designed to reliably support multiple smart thermostats and doorbells simultaneously. Compatible with leading brands like Nest, Ecobee, Honeywell, and Ring, it features premium copper wiring and flame-retardant materials for enhanced safety and durability. Ideal for professionals upgrading their smart home infrastructure to ensure stable, continuous power delivery. ## Description Power Up Multiple Thermostats / Doorbells: Replaces And Upgrades Underpowered Transformer With This 24V Ac Transformer, Offering Plenty Of Power For Single Or Multiple Thermostats And Doorbells At The Same Time Universal Compatibility: This 24V Transformer Fits For Nest, Ecobee, Honeywell And Sensi Smart Thermostats; Also Compatible With Ring Video Doorbell, Ring Video Doorbell 2, Ring Video Doorbell Pro, Nest Skybell Doorbell, And Other Devices That Require Constant 24 Volt Power For Operation Specification: Input Is 208-240 V/ Ac, 50/60 Hz; Output: 24 V/ 40 Va , Class 2 Transformer With Class B Insulation System Ru Certified And Safe Use: This 24 Volt Transformer Is Ru-Certified, Offers Reliable Performance Pure Copper, Anti Rust And Esd Protected : Use High-Quality Materials, High-Quality Silicon Steel Plate, All-Copper Enameled Wire, Nylon Flame-Retardant J Rubber Core, Flame-Retardant Tape, High-Temperature Resistance Lead And Vacuum Impregnation Varnish Treatment. Review: Stable voltage for doorbells. - Good quality product. Stable 24VAC voltage. Size is bigger than my expectation and heavier too. But works well. I use it for Ring doorbell. Review: Poor quality getting very hot even with no load - The transformer getting very hot and likely will damage soon due to excessive heat. Manufacturer used less number of coils turns to save money which is causing this issue. PS. Connected to 220v supply using the black and orange wires. It may blast and make a risk of fire. Not recommended…. ## Features - POWER UP MULTIPLE THERMOSTATS / DOORBELLS: replaces and upgrades underpowered transformer with this 24V AC transformer, offering plenty of power for single or multiple thermostats and doorbells at the same time - UNIVERSAL COMPATIBILITY: this 24v transformer fits for Nest, Ecobee, Honeywell and Sensi smart thermostats; Also compatible with Ring Video Doorbell, Ring Video Doorbell 2, Ring Video Doorbell Pro, Nest Skybell Doorbell, and other devices that require constant 24 volt power for operation - SPECIFICATION: Input is 208-240 V/ AC, 50/60 Hz; Output: 24 V/ 40 VA , Class 2 Transformer with Class B Insulation System - RU CERTIFIED AND SAFE USE: This 24 volt transformer is RU-certified, offers reliable performance - PURE COPPER, ANTI RUST AND ESD PROTECTED : Use high-quality materials, high-quality silicon steel plate, all-copper enameled wire, nylon flame-retardant J rubber core, flame-retardant tape, high-temperature resistance lead and vacuum impregnation varnish treatment ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B08P8NYPMK | | ASIN | B08P8NYPMK | | Batteries Required? | No | | Best Sellers Rank | #18,001 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #3 in Door Bell Transformers | | Color | multi | | Country of origin | United Arab Emirates | | Customer Reviews | 3.8 3.8 out of 5 stars (29) | | Customer reviews | 3.8 3.8 out of 5 stars (29) | | Date First Available | 28 November 2020 | | Date First Available | 28 November 2020 | | Included components | TRANSFORMER | | Item Package Quantity | 1 | | Item Weight | 150 g | | Item model number | RA-191-05860 | | Item model number | RA-191-05860 | | Manufacturer | Royal Apex | | Manufacturer | Royal Apex | | Package Dimensions | 9 x 7 x 5 cm; 150 g | | Package Dimensions | 9 x 7 x 5 cm; 150 g | | Part number | RA-191-05860 | | UPC | 704335537018 | ## Product Details - **Brand:** Royal Apex - **Item weight:** 150 Grams - **Mounting type:** Wall Mount - **Power source:** AC Adapter - **Specification met:** RU ## Images ![24VAC 40VA Thermostat and Doorbell Transformer, Power Supply Compatible with Nest, Ecobee, Sensi and Honeywell Thermostat, Nest Hello Ring Doorbells | Made in Vietnam - Image 1](https://m.media-amazon.com/images/I/61flQrqACbL.jpg) ## Customer Reviews ### ⭐⭐⭐⭐⭐ Stable voltage for doorbells. *by S***J on 18 July 2021* Good quality product. Stable 24VAC voltage. Size is bigger than my expectation and heavier too. But works well. I use it for Ring doorbell. ### ⭐ Poor quality getting very hot even with no load *by W***M on 28 March 2024* The transformer getting very hot and likely will damage soon due to excessive heat. Manufacturer used less number of coils turns to save money which is causing this issue. PS. Connected to 220v supply using the black and orange wires. It may blast and make a risk of fire. Not recommended…. ### ⭐ It never worked *by S***L on 27 September 2023* Tried this Transformer for google doorbell. But it didn’t work ## Frequently Bought Together - Royal Apex 24VAC 40VA Thermostat and Doorbell Transformer, Power Supply Compatible with Nest, Ecobee, Sensi and Honeywell Thermostat, Nest Hello Ring Doorbells | Made in Vietnam - Eujgoov Power Transformer AC 220V to AC 12V 24V 10W 50Hz Single EI Power Transformer Power Converters(24V) --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.vn/products/254258171-24vac-40va-thermostat-and-doorbell-transformer-power-supply-compatible-nest](https://www.desertcart.vn/products/254258171-24vac-40va-thermostat-and-doorbell-transformer-power-supply-compatible-nest) --- *Product available on Desertcart Vietnam* *Store origin: VN* *Last updated: 2026-05-22*