Warmflow Agentis Heat Only Oil Boiler 15–44kW

Warmflow Agentis Heat Only Boiler

The Warmflow Agentis Heat Only Oil Boiler is a high-efficiency internal oil boiler range designed for reliable central heating in homes and other suitable indoor heating applications. Available from 15kW to 44kW, the Agentis Internal Heat Only range combines Warmflow’s patented stainless-steel heat exchanger technology with a modern Riello low-NOx burner.

The range includes the I21, I26, I33 and I44 models, providing different heating output levels for a wide range of property sizes and heating requirements. Warmflow specifically designs the Agentis Internal range for installation in kitchens and utility rooms, with a compact white casing and front service access.

Warmflow Agentis Heat Only Models

Warmflow’s current specifications list the Agentis Internal Heat Only range from 15–44kW. The I21, I26 and I33 models share a compact casing approximately 865mm high × 413mm wide × 602mm deep, while the larger I44 is approximately 1155mm high × 595mm wide × 872mm deep.

High-Efficiency Stainless-Steel Heat Exchanger

At the heart of the Agentis range is Warmflow’s patented 5mm stainless-steel heat exchanger technology. The design provides efficient heat transfer while supporting the compact construction of the boiler.

Warmflow combines this technology with its latest Riello low-NOx burner, producing a high-efficiency oil heating system designed for modern central-heating applications.

The manufacturer’s technical documentation gives the nominal heat-output ranges and individual output points for the I21, I26, I33 and I44 models, with maximum nominal heat outputs of 21kW, 27.1kW, 32.7kW and 44kW respectively.

Designed for Indoor Installation

The Warmflow Agentis Heat Only boiler is part of the Agentis Internal range and is designed specifically for indoor installations.

Its compact dimensions and white casing make it suitable for kitchens, utility rooms and other appropriate indoor boiler locations. All four models provide front service access, helping heating engineers carry out routine servicing and maintenance.

Heat Only Configuration

The Agentis Heat Only is a heat-only oil boiler, not an integrated combi boiler.

This means the boiler provides the central-heating function while domestic hot water is arranged separately according to the property’s heating system design. The manufacturer’s specifications show no integrated domestic hot-water flow for these heat-only models.

This distinction is important because Warmflow also produces separate Agentis Internal Combi, Internal System and Internal Pumped models. The heat-only I21, I26, I33 and I44 should therefore not be confused with those variants.

Quiet Oil Boiler Operation

Warmflow highlights quiet operation as one of the features of the Agentis range. This makes the boiler suitable for indoor applications where controlling operating noise is important.

HVO Ready

The Warmflow Agentis Internal Heat Only range is identified by the manufacturer as HVO Ready.

HVO can provide an alternative liquid fuel option for compatible oil-heating installations. Any fuel conversion, commissioning or installation work should be completed in accordance with Warmflow’s current technical requirements and the requirements applicable to the installation.

Warmflow Agentis Heat Only Key Features

• 15–44kW output range
• I21, I26, I33 and I44 models
• Heat-only oil boiler configuration
• Patented 5mm stainless-steel heat exchanger technology
• Riello low-NOx burner
• Compact internal design
• Stylish white casing
• Designed for kitchen and utility-room installation
• Front service access
• Quiet operation
• HVO Ready
• Multiple flue options
• Suitable for a range of central-heating applications
• European supply available through Euro Fuel Supply

Warmflow Agentis Heat Only vs Pre-Pumped

The Agentis Heat Only and Agentis Internal Pumped ranges should not be treated as the same product.

The standard heat-only models are I21, I26, I33 and I44, while the pumped range uses I21P, I26P, I33P and I44P and includes a factory-fitted Grundfos UPM3 FLEX AS circulating pump.

Keeping these as separate product pages is also beneficial for SEO because customers searching for a standard heat-only boiler and customers specifically looking for a pre-pumped boiler have different purchase intent.

Frequently Asked Questions

What is the Warmflow Agentis Heat Only Boiler?

The Warmflow Agentis Heat Only is an internal oil-fired heat-only boiler range designed for central-heating applications. It is available in I21, I26, I33 and I44 models from 15–44kW.

What output sizes are available?

The Agentis Internal Heat Only range includes:

• I21: 15–21kW
• I26: 21–27kW
• I33: 27–33kW
• I44: 33–44kW

Is the Warmflow Agentis Heat Only a combi boiler?

No. It is a heat-only oil boiler. It does not provide integrated domestic hot-water production like the separate Agentis Internal Combi range.

Does it include a circulating pump?

The standard Agentis Heat Only models should not be confused with the pumped versions. The separate Agentis Internal Pumped range includes a factory-fitted Grundfos UPM3 FLEX AS circulating pump.

What burner does the Agentis use?

Warmflow specifies a Riello low-NOx burner for the Agentis Internal Heat Only range.

Is the Warmflow Agentis suitable for indoor installation?

Yes. The Agentis Internal Heat Only range is specifically designed for indoor installations, including kitchen and utility-room applications.

Is the Agentis Heat Only boiler HVO Ready?

Yes. Warmflow identifies the Agentis Internal Heat Only range as HVO Ready.

What are the dimensions of the Warmflow Agentis I21, I26 and I33?

The I21, I26 and I33 models are approximately 865mm high × 413mm wide × 602mm deep.

What are the dimensions of the Warmflow Agentis I44?

The I44 model is approximately 1155mm high × 595mm wide × 872mm deep.

Does the Agentis Heat Only include domestic hot water?

No. The heat-only models are designed for central heating and have no integrated DHW flow. A separate domestic-hot-water arrangement is required where hot water is needed.

What is the difference between Agentis Heat Only and Agentis System?

The Heat Only models provide the boiler heat source without the factory-fitted sealed-system package found on the separate Agentis Internal System range. The System range includes I21S, I26S and I33S and has an integrated circulating pump and sealed-system components.

Can I buy Warmflow Agentis boilers for European projects?

Euro Fuel Supply offers Warmflow heating products for customers across supported European markets, with availability and delivery dependent on the selected model and destination.