Corner Fireplace Insert with Water Boiler Prity A W20 – 5 kW + 21.1 kW Water

The Fire for the Room. Serious Heat for a Bigger House.

The Prity A W20 is the higher-capacity sibling of the Prity A W16, built around the same corner-mounted body but stepped up with a 21.1 kW water heat exchanger — enough to carry a larger central heating load across more radiators. 5 kW of radiant heat and the corner-facing glass still heat the room it stands in directly, while most of the fire's energy goes straight into your heating system.

Made in Bulgaria. EU Ecodesign compliant.

How Much Space Can It Heat?

Prity doesn't publish an official heated-area figure for the Prity A W20, so this is our own estimate, based on the heated-area-to-power ratio observed across comparable Prity models in our range (roughly 7.5 m² per kW). Here, that ratio applies to the unit's combined output of 26.1 kW — 5 kW radiating into the room plus 21.1 kW into the water circuit, which spreads its heat through radiators installed around the house rather than from the insert itself. Combined, that puts the Prity A W20 at approximately 195 m², depending on your home's insulation, radiator layout, and how the heating system is balanced.

Corner Placement That Changes How a Room Heats

Like the rest of the Prity A range, this insert is shaped to fill a room corner rather than a flat wall, radiating heat across a wide arc of the room instead of throwing it in a single direction. The angled side glass panels keep the fire visible from more of the room, while the corner position frees up the flat walls on either side for furniture.

A Larger Water Heat Exchanger for Bigger Homes

The Prity A W20 delivers 21.1 kW to its water heat exchanger at nominal output, alongside 5 kW of direct radiant heat into the room. The water tank holds 34 litres, with a maximum working pressure of 1.25 bar and 1″ water connections for both flow and return.

This is a boiler-type appliance: it must be connected to a working central heating system before use, and should never be run dry or disconnected from your water circuit. Installation and commissioning by a qualified heating engineer is required.

Clean Combustion, Class A Efficiency

The Prity A W20 achieves a combustion efficiency (η) of 80% and a seasonal space heating energy efficiency of 71%, with an energy efficiency index of 106 — placing it in energy class A. Emissions at nominal output: CO at 1238 mg/Nm³, particulate matter at 26 mg/Nm³, NOx at 97 mg/Nm³, and OGC at 20 mg/Nm³ — all within EU Ecodesign limits.

Fuel consumption at nominal output is 8.2 kg of dry wood per hour, reflecting the larger heat exchanger's demand. Flue gas temperature is 227°C, with a mass flow rate of 21.6 g/s.

A Wide, Tall Firebox

The combustion chamber measures 855 mm wide, 540 mm deep, and 315 mm high — sized to sustain the longer, hotter burns a larger boiler system needs to keep up with central heating demand.

Important Installation Note

The Prity A W20 uses a Ø200 mm flue outlet and requires a minimum chimney draught of 12.1 Pa. Please confirm your chimney connection is compatible with this diameter before ordering. Its corner geometry means installation requires careful planning of the surrounding hearth structure on both adjoining walls. At 152 kg, this is one of the heavier inserts in our range — the unit needs a floor and framing capable of supporting the weight, and professional installation, including connection to your heating system, is required, not optional.

Overall dimensions: 1010 × 700 × 790 mm (W × D × H).

30 Years of European Engineering Behind Every Weld

Prity has manufactured solid fuel heating appliances in Gorna Oryahovitsa, Bulgaria, since 1995. With more than 250 production staff and a range refined across three decades, the company builds inserts that earn their place in a home for years. Every unit is manufactured to the relevant EN standards and independently verified.

Your Prity A W20 comes with a 24-month manufacturer's warranty.

Everything You Get

• 5 kW of direct radiant heat, plus 21.1 kW to your water heat exchanger (26.1 kW combined)

• Corner-mounted design — fits neatly into any room corner, radiating heat across the whole space

• 34-litre water tank, 1.25 bar maximum working pressure, 1″ water connections

• Class A energy efficiency with a seasonal space heating energy efficiency of 71%

• Combustion efficiency (η) of 80%

• Wide firebox: 855 × 540 × 315 mm (W × D × H)

• Fuel consumption: 8.2 kg of dry wood per hour at nominal output

• Overall footprint: 1010 × 700 mm

• Flue outlet: Ø200 mm — confirm chimney compatibility before ordering

• Net weight: 152 kg

• 24-month manufacturer's warranty

Box Contents

Insert body with integrated water heat exchanger, heat-resistant glazed door, technical manual.

Use only dry, chemically untreated natural wood with a moisture content not exceeding 20%. Do not burn household waste, painted wood, plywood, or treated wood. This appliance must be connected by a qualified installer to a working central heating system before use — never operate it disconnected from your water circuit. Always consult a qualified installer before connecting the appliance to your chimney system, and before building the surrounding hearth structure for a corner installation. Note: this model requires a Ø200 mm flue connection and 1″ water connections.