# Door contact sensor BLOW HO-03F — reed switch magnetic door/window sensor

**URL:** https://aio.lv/en/product--blow-4928--11863641
**Data updated:** 2026-03-09 17:40 (EET)
**Category:** Smart Sensors
**Manufacturer:** BLOW
**Manufacturer code:** 4928#
**EAN:** 5900804098959
**Warranty:** 2 Years
**Availability:** Available for order
**Price:** 11.99 €
**Prices and availability valid until:** 2026-07-17 23:59
**Price without VAT (21%):** 9.91 EUR
**Can be purchased by legal entities:** Yes (invoice)
**Buy:** https://aio.lv/en/product--blow-4928--11863641

## Delivery options

| Delivery method | Delivery time | Cost |
|---|---|---|
| Office pickup (2b. Kengaraga str., Riga, Latvia, LV-1063) | 13.07.2026 | free |
| Pickup points | 16.07.2026 | 1.99 EUR |
| Courier delivery to door | 16.07.2026 | 4.99 EUR |

## Summary description

BLOW HO-03F is a door/window magnetic contact (reed) sensor designed to detect opening and closing of doors or windows. The compact contact sensor operates as a normally closed/open magnetic switch and is intended for integration with alarm panels, security systems or DIY monitoring setups. It provides reliable state reporting for perimeter protection and access control.

## Long description

BLOW HO-03F is a compact reed switch magnetic door/window sensor designed to detect the opening and closing of doors and windows. The sensor operates as a normally closed/open magnetic contact and is intended for integration with alarm panels, security systems and DIY monitoring setups. Its small form factor and straightforward wiring enable reliable state reporting for perimeter protection and basic access control applications.
Advantages
The BLOW HO-03F offers a minimal footprint and simple mechanical design that supports long-term, low-maintenance operation. As a reed contact device it provides fast and unambiguous switching when the magnet is moved away or brought close, ensuring clear open/closed signals. Installation requires only basic wiring and mounting, making it suitable for both professional installers and DIY users. The sensor is compatible with a wide range of alarm panels and wired input modules.
Suitable for
 Perimeter intrusion detection on doors and windows
 Integration with wired alarm panels and control units
 Home and small-office basic access control monitoring
 DIY security and monitoring projects
Key specifications
 Switch type: reed (magnetic) contact, normally closed/open operation
 Mounting: surface mount for door or window frames (two-piece sensor and magnet)
 Connection: wired contacts suitable for alarm panel input wiring
 Operating principle: magnetic actuation by separate magnet piece
 Typical applications: perimeter protection, access state reporting
 Form factor: compact inline contact housing for discreet installation
How to use
Mount the sensor body on the fixed frame and the magnet on the moving part of the door or window so that the two parts align when closed. Connect the sensor wires to the appropriate input terminals of the alarm panel or monitoring device, observing the panel's wiring diagram for normally closed or normally open configuration as required. Test operation by opening and closing the door or window and verifying the change of state on the control panel or monitoring system.
Usage recommendations
Place the sensor and magnet with minimal gap and firm alignment to ensure consistent reed actuation. Avoid installing the magnet near other strong magnetic sources or ferrous objects that could affect operation. For outdoor or damp locations, use appropriate sealing or protective housing to prevent moisture ingress. Periodically check wiring connections and physical mounting for secure contact and reliable performance.

## FAQ

### How much does the Door contact sensor BLOW HO-03F cost, and is it available for purchase?

The price is 11.99 € (valid at the time of publication and already includes all taxes). The item is available for order — 10 pcs. are in stock, and you can place your purchase right now with delivery across Latvia and Europe or choose pickup at the Riga collection point. We offer favorable purchase terms, including the option to split the payment into convenient monthly installments. Availability and price are updated in real time, so we recommend placing your order in advance.

### If I order this product today, when will I receive my order?

If you place your order today, delivery will be as fast and convenient as possible. You will be able to pick up your order on 13.07.2026 at the Riga pickup point or choose delivery across Latvia and Europe. We carefully inspect every purchase and pack it securely for safe transportation.

### What payment options are available?

AiO.lv offers several payment methods: Bank transfer, Bank cards on-line, Apple Pay, Google Pay. All transactions are 100% secure and encrypted.

### Can this product be purchased for a company (with VAT)?

Yes. AiO.lv works with legal entities in Latvia and across Europe. The product price already includes VAT. For certain product categories, as well as for companies from other EU countries with a valid VAT number, a 0% VAT rate may apply. We issue the invoice immediately after the order is placed, support electronic BIS invoices, and automatically generate all necessary accounting documents. You can complete the purchase for a company online — simply select the company profile and choose bank transfer as the payment method during checkout.

### What is the warranty period?

All BLOW products come with an official 2 Years warranty. It covers all manufacturing defects and malfunctions that may occur during use. The warranty is valid at all authorized BLOW service centers and through AiO.lv

### Can the product be returned after purchase?

Yes, you can return the product within 14 days of purchase if you bought it as a consumer (not a legal entity). Returns are possible without giving any reason — the main condition is that the product retains its original appearance and full set of accessories. We will make the process as simple and convenient as possible: just contact our customer support team, and we will help you arrange the return.

### Where should I contact for warranty service?

For warranty-related questions you can contact the AiO.lv (SIA VSPRO) customer support team. More information about warranty service: https://aio.lv/en/warranty

## Image

https://aio.lv/img/cache/product/11863641/67262282_large.webp