---
product_id: 52389645
title: "Flexvent 1/2"
brand: "flamco"
price: "€ 54.69"
currency: EUR
in_stock: null
reviews_count: 13
category: "Flamco"
url: https://www.desertcart.es/products/52389645-flexvent-1-2
store_origin: ES
region: Spain
---

# Automatic air venting Max temp 120°C peak Compact 1/2 inch size Flexvent 1/2

**Brand:** flamco
**Price:** € 54.69
**Availability:** ❌ Out of Stock

## Summary

> 💨 Keep your heating system flawless with the Flexvent 1/2 – the silent guardian of comfort!

## Quick Answers

- **What is this?** Flexvent 1/2 by flamco
- **How much does it cost?** € 54.69 with free shipping
- **Is it available?** Currently out of stock
- **Where can I buy it?** [www.desertcart.es](https://www.desertcart.es/products/52389645-flexvent-1-2)

## Best For

- flamco enthusiasts

## Why This Product

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

## Key Features

- • **Glycol-Compatible:** Works flawlessly with up to 50% glycol mixtures for versatile installations
- • **Precision Air Release:** Automatically vents trapped air to optimize heating efficiency
- • **Factory-Tested Quality:** Each valve is rigorously tested to ensure leak-free, reliable performance
- • **Compact & Durable Design:** Sleek brass construction fits tight spaces and resists corrosion
- • **High-Pressure Resilience:** Operates safely up to 10 bar peak pressure for robust systems

## Overview

The Flamco Flexvent 1/2 inch automatic air vent valve is engineered for residential heating systems, compatible with glycol content up to 50%. Its compact brass design supports continuous operation at temperatures up to 90°C (peak 120°C) and pressures up to 6 bar (peak 10 bar). Factory-tested for quality assurance, it ensures efficient air removal to prevent system airlocks, enhancing heating performance and longevity.

## Description

Free delivery and returns on all eligible orders. Shop Flamco Flexvent 1/2" Floatvent c/w shut-off valve - Automatic Air Vent 27740.

Review: Does exactly what it says on the box - Purchased this to replace the old barrel design plastic air vent on my central heating system that was leaking. It took considerably more effort to bleed and refill the system (and getting rid of the subsequent air locks), than to fit this. A couple of layers of white plumbers tape, and it fitted perfectly without any leaks. It is clearly better built than the plastic valve as well, and operates much better. Although it doesn't come with any instructions, if you download the Flamco manual it recommends that you loosen the cap before filling the system and tighten afterwards. The location of the valve is critical as well, it should be on the highest point of the system after the water pump to prevent air being drawn into the system. While not a "Silver bullet" for a central heating system with an airlock issue, the Flamco was not designed to be that. There are many reasons for airlocks occurring in a domestic CH scenario, and an airvent valve may or may not be the solution. If you purchase it as a replacement part with this in mind, you won't go wrong.
Review: Good quality - Great

## Features

- The Flamco Flexvent 1/2 inch vent valve is suitable for house installations with a glycol content of up to 50%.
- Thanks to its extremely compact shape, the Flexvent 1/2 inch bleed valve can be easily installed in any system that can be installed at a temperature below 90°C (with a peak of max. 120°C) and a pressure of 6 bar (with a peak of max. 10 bar).
- As a quality guarantee, every Flamco nozzle is tested before it leaves our factory.
- The Flexvent seal seat is protected from dirt as the protective chamber is placed on the float

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B00GXNNGPY |
| Batteries Required? | No |
| Batteries included? | No |
| Best Sellers Rank | 29,408 in DIY & Tools ( See Top 100 in DIY & Tools ) 320 in Central Heating System Accessories |
| Certification | CE, ISO 9001, RoHS |
| Colour | Red |
| Customer Reviews | 4.4 4.4 out of 5 stars (1,191) |
| Date First Available | 26 Nov. 2013 |
| Included Components | No |
| Item Package Quantity | 1 |
| Item Weight | 100 g |
| Item model number | 27740 |
| Manufacturer | Flamco |
| Material | Messing |
| Maximum Pressure | 10 Bars |
| Part Number | 27740 |
| Product Dimensions | 23 x 3 x 80 cm; 100 g |
| Size | R½" |

## Product Details

- **Brand:** Flamco
- **Exterior finish:** Brass
- **Inlet connection size:** 230 Millimeters
- **Inlet connection type:** 1 1/4 inch male thread
- **Item dimensions L x W x H:** 23 x 3 x 80 centimetres
- **Material:** Messing
- **Maximum operating pressure:** 10 Bars
- **Number of ports:** 2
- **Outlet connection size:** 0.5 Inches
- **Outlet connection type:** External thread

## Images

![Flexvent 1/2 - Image 1](https://m.media-amazon.com/images/I/11e3duNMCaL.jpg)
![Flexvent 1/2 - Image 2](https://m.media-amazon.com/images/I/319alBD4EAL.jpg)
![Flexvent 1/2 - Image 3](https://m.media-amazon.com/images/I/31E8oqT8EpL.jpg)
![Flexvent 1/2 - Image 4](https://m.media-amazon.com/images/I/31WlrfLnYPL.jpg)
![Flexvent 1/2 - Image 5](https://m.media-amazon.com/images/I/31ZBMQuD2IL.jpg)

## Questions & Answers

**Q: Hello - does this connect directly to 15mm copper pipe or does it need an adaptor?**
A: Hi, it has a 1/2" BSP male thread, so you would need an adaptor to fit it onto 15mm copper.

**Q: Can I screw this straight into the top of my towel rail replacing the manual bleed valve? Will I need ptfe tape?**
A: This type of valve isn't really designed for what you are proposing, more to remove air from whole systems. You may wish to consider one of the smaller valves specifically designed for radiators. Try "Aladdin Micro Barlo 6mm Fully Automatic Self Bleeding Radiator Valve" or perhaps have a chat with your local plumbers' merchant.

**Q: what is the Product Dimensions?**
A: Flexvent Dimensions
Ø [mm]: 30
H. [mm]: 75.5

Connection
R 1⁄2"

**Q: Does the valve need to be fitted vertically**
A: As the CH water lifts a plunger against gravity, if the valve was other than upright, it may not operate to its full capacity

## Customer Reviews

### ⭐⭐⭐⭐⭐ Does exactly what it says on the box
*by L***G on 4 October 2020*

Purchased this to replace the old barrel design plastic air vent on my central heating system that was leaking. It took considerably more effort to bleed and refill the system (and getting rid of the subsequent air locks), than to fit this. A couple of layers of white plumbers tape, and it fitted perfectly without any leaks. It is clearly better built than the plastic valve as well, and operates much better. Although it doesn't come with any instructions, if you download the Flamco manual it recommends that you loosen the cap before filling the system and tighten afterwards. The location of the valve is critical as well, it should be on the highest point of the system after the water pump to prevent air being drawn into the system. While not a "Silver bullet" for a central heating system with an airlock issue, the Flamco was not designed to be that. There are many reasons for airlocks occurring in a domestic CH scenario, and an airvent valve may or may not be the solution. If you purchase it as a replacement part with this in mind, you won't go wrong.

### ⭐⭐⭐⭐⭐ Good quality
*by R***A on 5 April 2025*

Great

### ⭐⭐⭐⭐ It's 1/2 inch and comes with a closure valve.
*by M***F on 21 December 2019*

Easy to install and seems to work. Give it 4 weeks and I'll come back and buy a few more if it successfully clears air buildup in my manifolds.

## Frequently Bought Together

- Flamco Flexvent 1/2" Floatvent c/w shut-off valve - Automatic Air Vent 27740
- LOCTITE 55 Pipe Thread Sealant, Non Curing Thread Sealant for Plumbing Pipes and Fittings, Reliable Fast Action Pipe Sealant for Metal and Plastic, 50m

---

## 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.es/products/52389645-flexvent-1-2](https://www.desertcart.es/products/52389645-flexvent-1-2)

---

*Product available on Desertcart Spain*
*Store origin: ES*
*Last updated: 2026-01-23*