Vertical Fireplace Insert with Water Boiler Prity VM W15 – 5 kW + 15 kW Water

The Fire for the Room. The Heat for the Whole House — In a Narrow Frame.

The Prity VM W15 takes the tall, narrow body of the Prity VM and builds a water heat exchanger into it: most of the energy from every fire goes directly into your central heating system, while 5 kW of radiant heat and the tall vertical firebox still warm the room it stands in directly. It's a boiler insert for spaces where width is limited but height is available.

Made in Bulgaria. EU Ecodesign compliant.

How Much Space Can It Heat?

Prity doesn't publish an official heated-area figure for the Prity VM W15, 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 20 kW — 5 kW radiating into the room plus 15 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 VM W15 at approximately 150 m², depending on your home's insulation, radiator layout, and how the heating system is balanced.

A Tall Firebox with Real Flame Height

The combustion chamber measures 366 mm wide, 411 mm deep, and 524 mm high — notably taller than it is wide, giving flames room to rise rather than spreading low and flat. Combined with the insert's 900 mm overall height, the Prity VM W15 keeps the vertical, tower-of-fire character of the standard VM while adding a full water heat exchanger behind it. The ceramic glass door is kept clear by the secondary air wash system, which runs a continuous curtain of fresh air across the inner glass surface during burning.

A Water Heat Exchanger Built for Central Heating

The Prity VM W15 delivers 15 kW to its water heat exchanger at nominal output, alongside 5 kW of direct radiant heat into the room. The water tank holds 20 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.

A Narrow Footprint for Tighter Spaces

At just 500 mm wide, the Prity VM W15 fits into narrower chimney breasts and tighter alcoves than most of our boiler inserts, without giving up the water heat exchanger a household with central heating actually needs.

Clean Combustion, Class A Efficiency

The Prity VM W15 achieves a combustion efficiency (η) of 78.3% and a seasonal space heating energy efficiency of 69%, with an energy efficiency index of 105 — placing it in energy class A. Emissions at nominal output: CO at 1167 mg/Nm³, particulate matter at 25 mg/Nm³, NOx at 93 mg/Nm³, and OGC at 17 mg/Nm³ — all within EU Ecodesign limits.

Fuel consumption at nominal output is 6.4 kg of dry wood per hour, reflecting the added load of heating both the room and your water circuit. Flue gas temperature is 223°C, with a mass flow rate of 21.2 g/s.

Important Installation Note

The Prity VM W15 uses a Ø200 mm flue outlet and requires a minimum chimney draught of 13.7 Pa. Please confirm your chimney connection is compatible with this diameter before ordering. At 104 kg, 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: 500 × 520 × 900 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 VM W15 comes with a 24-month manufacturer's warranty.

Everything You Get

• 5 kW of direct radiant heat, plus 15 kW to your water heat exchanger (20 kW combined)

• Tall, vertical firebox — taller flames and a narrower footprint than our other boiler inserts

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

• Class A energy efficiency with a seasonal space heating energy efficiency of 69%

• Combustion efficiency (η) of 78.3%

• Firebox: 366 × 411 × 524 mm (W × D × H)

• Fuel consumption: 6.4 kg of dry wood per hour at nominal output

• Compact width: just 500 mm — fits narrower chimney breasts and alcoves

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

• Net weight: 104 kg

• 24-month manufacturer's warranty

Box Contents

Insert body with ceramic glass door and integrated water heat exchanger, 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. Note: this model requires a Ø200 mm flue connection and 1″ water connections.