Vega Hot Water Circulators

A Vega hot water circulator is a small wet-rotor pump that keeps hot water moving around a loop, so it arrives hot at the tap in seconds instead of running cold water down the drain first. It also circulates water through solar geysers, heat pumps, underfloor heating and radiator systems. Vega offers three three-speed models with threaded unions included. This guide covers how to choose, install and set one.

Where a circulator is used

• Hot water return loops in houses, guest houses and hotels, so hot water is instant at far taps.
• Solar water heating with a separate panel and tank, where the pump moves water between them.
• Heat pumps heating a storage tank or pool.
• Underfloor heating and radiators in closed heating circuits.

A circulator is not a booster pump. It moves water around a closed loop against pipe friction only. It will not raise the pressure at your taps. For low pressure see the Vega booster pumps.

Models and prices

The model code gives the connection size, the approximate maximum head in metres and the port-to-port length: the UPS25-4-180 has 25 mm connections, about 4 m of head and a 180 mm body. All three run on 220–240V, 50 Hz with a three-position speed switch.

Specifications

Choosing the size

1. Flow. A domestic return loop needs very little flow, often under 1 m³/h. Heating circuits need about 1 litre per minute for every kW of heat, at a 15 °C temperature drop.
2. Head. Add up the friction of the loop: pipe length, fittings, valves and the heater or collector. Most house loops need 1 – 3 m.
3. Speed. Start on the lowest speed that gives hot water quickly or the design temperature drop. Higher speeds only add noise and power use.

For a single house loop the UPS25-4-180 is usually enough. Choose the UPS25-7-180 for long loops, larger houses and solar collectors, and the UPS32-8-180 for bigger heating circuits and guest houses.

Installation notes

• Motor shaft horizontal. Install on a vertical pipe run with the arrow in the direction of flow, so the wet rotor is lubricated and air can escape.
• Isolating valves on both sides make it easy to change the pump.
• Bleed the air before starting; a circulator that runs dry is damaged within minutes.
• Timer or thermostat on a return loop saves power: run it only at the times hot water is used.
• Protect from dripping water; the pump is IP44, not waterproof.

Frequently asked questions

Related guides

• Vega Surface Pumps
• Vega Solar Pumps
• Vega Pumps
• Vega Hot Water Circulator Pumps — shop the category