Wilo Yonos PICO 25/1-4-130 Heating Circulator Pump | 4215514

Description

The Wilo Yonos PICO 25/1-4-130 (article no. 4215514) is an electronically controlled high-efficiency circulator for hot-water heating systems. Its ECM synchronous motor draws as little as 4 W and never more than 20 W, with an Energy Efficiency Index of ≤0.18 — comfortably better than the 0.20 benchmark for the most efficient circulators.

With a maximum head of 4.3 m, flow up to 2.7 m³/h and the standard 130 mm port-to-port length with G 1½ connections, it is sized for smaller homes, flats and compact underfloor heating circuits. Choose variable differential pressure (Δp-v) for radiators, constant differential pressure (Δp-c) for underfloor heating, or one of three fixed speeds, all set with a single green operating button, while the LED display shows live power draw in watts and flow in m³/h.

4.3 m

Max. head

2.7 m³/h

Max. flow

4–20 W

Power consumption

≤0.18

EEI

130 mm

Port-to-port

G 1½

Connections

Good to Know

Is 4.3 m enough? Wilo's own setting guide rates the /1-4 for radiator systems of up to around 15 radiators and underfloor heating of up to around 120 m². For larger systems, the 25/1-6 or 25/1-8 versions of the same pump offer more head in the identical 130 mm body.

Application & Installation

This pump is designed exclusively for closed hot-water heating systems using heating water to VDI 2035 or water-glycol mixtures up to 50%. It is not suitable for potable domestic hot water circulation. The motor must be installed horizontally with the electrical connection never facing upwards, and the motor must not be thermally insulated — keep the four condensate drain openings clear.

Safety & Regulations

Electrical connection must be made by a qualified electrician in accordance with BS 7671. The pump must be earthed and protected by an RCD, with a maximum back-up fuse of 10 A slow-blow and a fixed supply via a connector or all-pole switch with at least 3 mm contact separation. Never operate the pump with phase-angle control. The housing and motor get hot — allow the system to cool and close the isolating valves before removing or rotating the pump head.

Key Features

Three ways to run

Δp-v halves the head as flow drops — ideal for TRV radiator systems and reducing valve noise. Δp-c holds a constant head for UFH. Constant speed I, II, III for fixed-resistance circuits.

Live energy display

The LED display shows the setpoint in 0.1 m steps, then alternates between current power in W and current flow in m³/h.

One-button setup

Everything is set with the green operating button. Factory setting is Δp-v at ½ Hmax, and all settings are retained if the power is interrupted.

Self-venting & restart

The pump vents automatically on first start; a 10-minute venting function and manual restart (to free a rotor after summer standstill) are available from the function key.

Blocking-current proof motor

ECM synchronous motor with integrated motor protection, automatic deblocking and a built-in particle filter — completely maintenance-free.

Wilo-Connector wiring

Tool-light Wilo-Connector plug for the mains lead, and a rotatable motor head to suit the pipework orientation.

Technical Specifications

Identification

Manufacturer

Wilo

Model

Yonos PICO 25/1-4-130

Article number

4215514

Pump type

Glandless high-efficiency circulator, screwed connection

Hydraulic Data

Maximum head

4.3 m (adjustable down to 0.5 m)

Maximum flow

2.7 m³/h

Maximum operating pressure

10 bar (PN 10)

Minimum suction head

0.5 m at 50°C; 3 m at 95°C

Fluid temperature

−10°C to +95°C

Ambient temperature

−10°C to +40°C

Permitted fluids

Heating water to VDI 2035; water-glycol up to 50%

Motor & Electrical

Mains connection

1~230 V ±10%, 50/60 Hz

Power consumption P1

4 W min. / 20 W max.

Rated power P2

15 W

Speed range

700–3,400 rpm

Energy Efficiency Index (EEI)

≤0.18

Protection class

IPX4D

Insulation class

F

Max. back-up fuse

10 A slow-blow

Inrush current

<5 A

Electrical connection

Wilo-Connector

Materials

Pump housing

Grey cast iron

Impeller

PP-GF40

Shaft

Stainless steel

Bearing

Carbon, metal-impregnated

Dimensions & Connections

Port-to-port length

130 mm

Pump connection

G 1½ (for Rp 1 / DN 25 screwed connections)

Pump dimensions (L x W x H)

138 x 131 x 102 mm

Net weight

Approx. 1.7 kg

In the Box & Compliance

Scope of delivery

Circulator with 2 gaskets, Wilo-Connector, installation instructions

Thermal insulation shell

Available as an accessory (not included)

Approvals

CE, VDE, EAC; ErP Regulation 641/2009 as amended by 622/2012

Frequently Asked Questions

What does 25/1-4-130 mean?

25 = screwed connection size (DN 25 / Rp 1, on G 1½ pump threads), 1-4 = head adjustable from about 1 m (down to 0.5 m) up to a nominal 4 m (4.3 m actual maximum), 130 = 130 mm port-to-port length.

Which setting should I use for radiators or underfloor heating?

Use Δp-v for two-pipe radiator systems with TRVs, and Δp-c for underfloor heating, large-bore pipework or single-pipe systems. Constant speed suits circuits with fixed resistance needing a steady flow.

Can I use it on domestic hot water (secondary return)?

No. The Yonos PICO is designed exclusively for closed hot-water heating systems. Potable hot water circulation needs a pump specifically rated for drinking water.

Can I switch it on and off from my boiler or wiring centre?

Yes, but the supply must be a clean sinusoidal 230 V — never phase-angle controlled. Any switching relay must handle an inrush of at least 5 A, and mains switching should not exceed 100 on/off cycles per 24 hours.

What if the pump will not start after the summer?

The pump attempts an automatic restart when it detects a blocked rotor. If E10 remains on the display, press the function key twice to run the 10-minute manual restart.

Is it noisy when first fitted?

Some noise is normal until air is cleared. The pump vents itself on first start; if needed, press the function key once to run the 10-minute venting function. Persistent noise can indicate low system pressure — check against the minimum suction head.

BTU Calculator

BTU & WATT Calculator

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)

Calculate

Required Heating

0

Watts

0

BTUs