---
product_id: 48082193
title: "Honeywell Cyl Stat L641A1039"
brand: "honeywell"
price: "RM595"
currency: MYR
in_stock: true
reviews_count: 8
url: https://www.desertcart.com.my/products/48082193-honeywell-cyl-stat-l641a1039
store_origin: MY
region: Malaysia
---

# Snap Action SPDT Micro Switch Tamperproof Temperature Setting Optional Manual Setting Knob Honeywell Cyl Stat L641A1039

**Brand:** honeywell
**Price:** RM595
**Availability:** ✅ In Stock

## Summary

> 🎯 Take command of your hot water system with precision and peace of mind!

## Quick Answers

- **What is this?** Honeywell Cyl Stat L641A1039 by honeywell
- **How much does it cost?** RM595 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.com.my](https://www.desertcart.com.my/products/48082193-honeywell-cyl-stat-l641a1039)

## Best For

- honeywell enthusiasts

## Why This Product

- Trusted honeywell brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Secure & User-Friendly:** Tamperproof settings protect your comfort while keeping adjustments simple.
- • **Versatile Compatibility:** Seamlessly switches pumps, boilers, and zone valves for total system control.
- • **Effortless Installation & Access:** Surface mount with easily accessible wiring terminals for quick setup.
- • **Built to Last with Safety in Mind:** Double insulated design ensures reliable, worry-free operation.
- • **Precision Control at Your Fingertips:** Manual knob lets you fine-tune temperature with ease and confidence.

## Overview

The Honeywell L641A1039 Cylinder Thermostat is a compact, surface-mounted device designed for domestic hot water cylinders. Featuring a snap action SPDT micro switch, tamperproof temperature settings, and an optional manual knob, it offers precise, reliable control for heating pumps, boilers, and zone valves. Its double insulated construction and accessible wiring terminals make installation safe and straightforward, ideal for indoor use.

## Description

Product Description The L641A Cylinder Thermostat is designed for surface mounting on domestic hot water cylinders. It can be used to switch directly a wet central heating circulating pump or boiler, or to operate spring return and motor open/motor close zone valves. Box Contains 1 x L641A1039 Stat

Review: Great replacement and easy to install - Easy to install, works very well
Review: Honeywell cylinder thermostat. - Easy to fit and nice and compact unit to replace old type thermostat. Works well and temperature dial easy to adjust.

## Features

- Snap Action SPDT Micro Switch
- Wiring Terminals Easily Accessible
- Tamperproof Temperature Setting
- Optional Manual Setting Knob Supplied
- Double Insulated

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B003DTIWGO |
| Backlight | No |
| Best Sellers Rank | 190,057 in DIY & Tools ( See Top 100 in DIY & Tools ) 166 in Thermostats 18,499 in Electrical |
| Brand | Honeywell |
| Brand Name | Honeywell |
| Colour | White |
| Connectivity Protocol | Wi-Fi |
| Connectivity Technology | Wired and Wi-Fi |
| Control Method | Touch |
| Control Type | Button Control |
| Controller Type | knob,manual |
| Controller type | knob,manual |
| Customer Reviews | 4.6 out of 5 stars 769 Reviews |
| Display Type | manual |
| Finish Type | Mixed |
| Global Trade Identification Number | 05023220200093 |
| Included Components | Cylinder Stat |
| Item Type Name | Cylinder Stat |
| Manufacturer | Honeywell |
| Manufacturer Part Number | L641A1039 |
| Material Type | Plastic |
| Model Name | Cylinder Stat |
| Model Number | L641A1039 |
| Model name | Cylinder Stat |
| Mounting Type | Surface Mount |
| Number of Batteries | 2 AA batteries required. |
| Number of Items | 1 |
| Power Source | AC |
| Product Style | Modern |
| Special Features | Manual Setting Knob, Tamperproof Temperature Setting |
| Special feature | Manual Setting Knob, Tamperproof Temperature Setting |
| Specific Uses For Product | Indoor use only |
| Specific uses for product | Indoor use only |
| Temperature Control Type | Manual |
| Unit Count | 1.0 count |
| Voltage | 230 Volts |

## Product Details

- **Brand:** Honeywell
- **Colour:** White
- **Connectivity technology:** Wired and Wi-Fi
- **Controller type:** knob,manual
- **Included components:** Cylinder Stat
- **Model name:** Cylinder Stat
- **Power source:** AC
- **Special feature:** Manual Setting Knob, Tamperproof Temperature Setting
- **Specific uses for product:** Indoor use only
- **Temperature Control Type:** Manual

## Images

![Honeywell Cyl Stat L641A1039 - Image 1](https://m.media-amazon.com/images/I/51LnYkZr-VL.jpg)

## Questions & Answers

**Q: I need a thermostat to show the tempereture of the hot water tank. It will consist of sensor wire 3 meters and an indicator to see the tempereture in**
A: These units do not have a gauge attached. They are strapped on with an 'elasticated wire  and make contact with the cylinder by cutting a suitable hole in the insulation. I'd think that there may well be a suitable gauge out there somewhere. I could do with one myself actually so I'll have a look on 'google' By the way I'd go for one that does not need to be powered and works on contact.

**Q: why are there no screws to undo to hold the cable?**
A: The unit comes with a flexible tie (same as that used for net curtains) that goes around the cylinder. This tie has hooks and the thermostat has eyes. Thus the hook and eye system keep the unit tight to the cylinder. Make are that the thermostat has metal to metal contact so that it can register the temperature of the hot water.

**Q: Why does this say 2x AA batteries required, this should be mains?**
A: 100% no batteries required it is hard wired into your heating / hot water junction box.

**Q: I have  potterton ptt2 water cylinder thermostat with sensor which is obsolete now . would this honeywell l641a1039 be ok as a replacement**
A: The Potterton PTT2 is not a conventional Cylinder Thermostat as it’s wired externally to the Tank with it’s own temp sensor. Sadly as you mentioned it’s now obsolete. The only option (if you can’t find another PTT2) is to replace it with a terminal box with heat resistant flex outlet to the new stat. Up to 3 wires from the original PTT2 will need to go to the new stat, new stat instructions will confirm it.

Finally the live wires will then be redundant and will require to be either terminated or spurred to a new useful output (plug socket box, a lamp etc) 

Please ensure a qualified electrician does ANY electrical work or changes in your home heating setup.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Great replacement and easy to install
*by M***N on 25 May 2026*

Easy to install, works very well

### ⭐⭐⭐⭐⭐ Honeywell cylinder thermostat.
*by M***G on 28 April 2025*

Easy to fit and nice and compact unit to replace old type thermostat. Works well and temperature dial easy to adjust.

### ⭐⭐⭐⭐ Don't unscrew everything like I did!
*by J***H on 26 November 2020*

Good product - would buy again. Important: when removing plastic outer casing in order to connect the mains wire - you only need to unscrew the single long corner screw and carefully remove the plastic rotary dial (just pulls off). The casing should tilt up and pull away freely exposing the mains wire connection area. Don't do what I did and unscrew any of the other screws because if feels 'stuck' -> if you do you will only completely mess up the temperature sensing element.

## Frequently Bought Together

- Honeywell L641A1039 Cylinder Stat, 230 V
- HONEYWELL ST9400C Thermostat Programmer. 7, 2-Channel, 3 on/Off per Day, 24 V, White, 1
- Honeywell T6360B1028 Room Thermostat, 230/240V, White, 1

---

## 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.com.my/products/48082193-honeywell-cyl-stat-l641a1039](https://www.desertcart.com.my/products/48082193-honeywell-cyl-stat-l641a1039)

---

*Product available on Desertcart Malaysia*
*Store origin: MY*
*Last updated: 2026-08-11*