Vaillant WH40/2 Low Loss Header with Insulation | 0020248932 | 70 kW

Description

The Vaillant WH40/2 Low Loss Header with Insulation is a compact, horizontally mounted hydraulic separator designed for Vaillant ecoTEC plus 48 kW and 64 kW commercial boilers. It helps maintain a consistent boiler flow rate, supports stable water temperatures across downstream heating circuits, and is supplied with EPP insulation to reduce heat loss in the plant room. With a maximum system capacity of 70 kW net input, it is a practical choice for new, clean commercial heating installations where space is limited.

70 kW

Net input at 20K

40 kW

At 11K spread

3.5 m³/h

Maximum flow rate

1.4 mbar

Pressure drop

1¼"

BSP female connection

EPP

Insulation included

Important installation note: Vaillant low loss headers are suitable only for new, clean systems up to 70 kW net input using correctly inhibited water. For systems where water cleanliness cannot be assured, a plate heat exchanger should be considered instead.

Compatibility: The WH40/2 is intended for use with Vaillant ecoTEC plus 48 kW and 64 kW boilers and can be mounted horizontally beneath the boiler. Always confirm system design, flow requirements and clearance requirements before ordering.

Installer tip: Vaillant recommends fitting a dirt filter in the return pipework between the low loss header and heating circuits to help prevent system debris from entering the boiler.

Key Features

Hydraulic separation

Helps decouple the boiler circuit from heating circuit pumps, reducing unwanted interaction between flows.

Consistent boiler flow

Supports the correct water flow through the boiler for reliable operation across varying system demands.

Multiple heating circuits

Enables a constant temperature supply to reach several heating circuits downstream of the header.

Low pressure loss

The 1.4 mbar pressure drop helps meet system flow requirements with minimal hydraulic resistance.

EPP insulation supplied

The included insulation helps minimise heat loss and maintain more stable plant room temperatures.

Space saving layout

Designed for horizontal installation under compatible Vaillant boilers, making it suitable for restricted plant rooms.

Technical Specifications

General

Brand

Vaillant

Product type

Horizontal low loss header kit with insulation

Manufacturer part number

0020248932

Model

WH40/2

Colour

Black

Performance

Maximum system capacity

70 kW net input at 20K temperature spread

Capacity at 11K spread

40 kW

Maximum flow rate

3.5 m³/h / 3,500 litres per hour

Pressure drop

1.4 mbar

Connections and dimensions

Connection

1¼ inch BSP female

Width

114 mm

Length

342 mm

Height

200 mm

Depth

260 mm

Compatibility and application

Compatible boilers

Vaillant ecoTEC plus 48 kW and 64 kW

Mounting orientation

Horizontal, suitable for installation beneath the boiler

System requirement

New, clean systems with correctly inhibited water

Included insulation

EPP insulation supplied as standard

Frequently Asked Questions

Which Vaillant boilers is the WH40/2 compatible with?

The Vaillant WH40/2 is designed for use with ecoTEC plus 48 kW and 64 kW boilers. It is a compact, horizontal low loss header intended to fit beneath the boiler where the installation layout allows.

What size heating system can it support?

It is rated for systems up to 70 kW net input at a 20K temperature spread. At an 11K spread, its stated capacity is 40 kW.

Why does a heating system need a low-loss header?

A low loss header provides hydraulic separation between the boiler and heating circuits. This helps maintain stable flow through the boiler while allowing downstream circuit pumps to operate independently.

Does the WH40/2 include insulation?

Yes. The WH40/2 is supplied with EPP insulation as standard, helping to reduce heat loss from the header and improve plant room comfort.

Can it be used on an existing heating system?

Vaillant states that its low loss headers are suitable only for new, clean systems with correctly inhibited water. For existing systems where cleanliness cannot be guaranteed, a plate heat exchanger may be the more appropriate solution.

Is additional system protection recommended?

Yes. Vaillant recommends a dirt filter in the return pipework between the low loss header and the heating circuits to help prevent debris from reaching the boiler.

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Room Dimensions

Length (in m):

Width (in m):

Height (in m):

Room Type

Living Room

Bedroom

Kitchen

Bathroom

Conservatory

Hallway

Glazing Type

Single Glazed

Double Glazed

Triple Glazed

External Walls

0 Wall

1 Wall

2 Walls

3 Walls

4 Walls

Insulation Level

Poor

Average

Good (New Build)

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