# Heating pump controller TECH ST-20 black

**URL:** https://aio.lv/en/product--tech-st20bk--11867659
**Data updated:** 2026-03-09 17:44 (EET)
**Category:** Control Systems
**Manufacturer:** TECH
**Manufacturer code:** ST20BK
**EAN:** 5901445470012
**Warranty:** 2 Years
**Availability:** Out of stock

## Summary description

TECH ST-20 is a compact controller for heating (CO) pumps, supplied in black finish. It provides basic control functions for circulating pumps in central heating systems, enabling on/off operation and protection against dry run or overload depending on installation. Suitable for residential and light commercial heating systems where reliable pump switching and simple control are required.

## Long description

TECH ST-20 black is a compact heating pump controller designed for on/off control of circulating pumps in central heating (CO) systems. Housed in a black finish, the device offers basic automation features to switch a heating pump according to an external control signal and to protect the pump from operation under unsafe conditions. The controller is intended for use in residential and light commercial installations where straightforward pump switching and reliable basic protection are required.
Advantages
The controller provides simple and reliable on/off switching for circulating pumps while occupying minimal space. Its compact design and clear function make installation and integration into existing heating circuits straightforward. The device includes protection features that reduce the risk of dry run and overload when configured according to the installation, contributing to extended pump lifetime and reduced maintenance needs.
Suitable for (tasks / use cases)
On/off control of circulating pumps in residential central heating systems
Basic pump protection in small commercial heating installations
Replacement of analog or manual pump switches with automated control
Integration into simple heating circuits that require reliable pump switching
Key specifications
Function: on/off control for circulating heating pumps
Protection features: dry run and overload protection when installed accordingly
Design: compact housing in black finish suitable for mounting in plant rooms or service cupboards
Application: intended for residential and light commercial central heating systems
How to use
Install the TECH ST-20 black controller in the pump electrical circuit following local electrical codes and the pump manufacturer’s recommendations. Connect the controller input to the system control signal or thermostat and wire the output to the pump motor circuit so that the device performs on/off switching. Configure any available protection settings to match pump specifications and system conditions to enable dry run and overload protection where applicable. Verify correct operation by cycling the heating system and observing pump start/stop behavior.
Usage recommendations
Fit the controller in a dry, ventilated location accessible for inspection. Ensure wiring and protective devices comply with national wiring regulations and the pump’s electrical ratings. Periodically check connections and functional operation as part of routine heating system maintenance.

## FAQ

### What payment options are available?

AiO.lv offers several payment methods: Bank transfer. 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 TECH 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 TECH 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

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