Thermotec Edge 25kW single phase Inverter Pond Heat Pump

Thermotec Edge 25kW single phase Inverter Pond Heat Pump

Year round pond heating with a choice of outputs and electrical supplies

The Thermotec Edge 25kW single phase is an inverter air source heat pump for suitable koi pond and swimming pool installations. This individual listing is the single phase version. It has a horizontal air discharge, Wi-Fi control and a recommended water flow of 10.9m³/h. Match that flow and the electrical supply to the proposed installation before ordering.

Edge is the successor to the Thermotec Pro range. It is designed to adjust compressor and fan operation as the heat demand changes. Compare it with other options in our pond heating range, taking account of the desired water temperature, heating season and installation conditions.

Understand the heating output before choosing a size

The published normal heating output for this model is 3.8-25.80kW at 27°C air and 26°C inlet water, and 3.300-20.20kW at 15°C air and 26°C inlet water. These are specified test conditions, not a prediction for every winter day. A heat-loss assessment should use the conditions in which you intend to run the heater.

Those colder air figures are especially relevant when comparing pond heaters. The nominal rating is a useful model identifier, but it is not a promise that the same heat will be available throughout a British winter. Boost mode and normal inverter operation also need to be distinguished when comparing models. Select the unit for the required winter duty, rather than relying on a brief maximum output or a swimming pool sizing chart.

Which Edge model suits your pond?

The 25kW is one of the larger single phase Edge options, with a recommended flow of 10.9m³/h. At this level, checking the circulation system is particularly useful before ordering: the nominal output of the heater and the maximum advertised flow of a pond pump do not establish how the completed system will perform. Compare with the 20.5kW and 30kW models against the same winter duty.

The larger Edge options also require more water flow. Increasing heater capacity without checking the existing pump and pipework can leave an installation unable to supply the necessary circulation. It is worth checking the complete design at the same time as selecting the heater, especially where an existing filter return is being adapted.

Thermotec Edge 25kW single phase specifications

Model	25kW single phase
Electrical phase	Single phase
Normal heat output at A27/W26	3.8-25.80kW
Normal heat output at A15/W26	3.300-20.20kW
Recommended water flow	10.9m³/h
Operating air range	−15–43°C
Refrigerant	R32
Air discharge	Horizontal
Wi-Fi	Included
Control app	Smart Life

Choose the electrical version as carefully as the heating capacity. A three phase model requires a suitable three phase supply and cannot simply replace a single phase appliance on the same connection. An electrician should check the exact selected unit, circuit protection, cable route and supply capacity before installation.

Outdoor positioning and airflow

The Edge must have an unrestricted supply of outdoor air. A suitable location needs room around the air intake, a clear discharge route and access for inspection and servicing. Avoid arrangements that trap cold discharged air against a wall or send it straight back into the intake. A decorative enclosure must not compromise the clearances in the installation manual.

Place the unit on a stable base and provide a route for condensate to drain away. Think about the direction of the fan outlet in relation to paths, patios and neighbouring property. The published noise range varies with model and operating load; the quietest figure represents only one operating condition, so sensible positioning remains important even with an inverter heat pump.

The Edge installation diagram shows 1,500mm clear in front of the air outlet, 500mm above, 700mm at each side and 300mm behind the unit. Check the orientation in section 3.2 of the Edge installation manual when planning your base and pipework. These spaces keep the airflow clear; do not box the heater into a tight enclosure or direct its cold exhaust back towards the air inlet.

Plumbing into a filtered return circuit

The manual places the heater after the circulation pump and filter. Where chemical dosing equipment is present on a pool system, the installation sequence must follow the manufacturer’s guidance. Use a bypass arrangement to regulate the flow through the heater and allow isolation for maintenance. Check the supplied unions and actual pipe sizes before ordering fittings; nominal imperial and metric pipe sizes should not be assumed interchangeable.

Pipework should be adequately supported and arranged so the heat exchanger can be drained when needed. Check the real flow at the heater after the resistance of filters, valves, bends and pipe length has been allowed for. The heat pump provides heating through the water circuit; it does not replace the pond’s filtration or circulation pump.

Inverter control and running costs

Inverter operation enables the unit to reduce output as the water approaches its target temperature, instead of relying solely on repeated full power starts and stops. Its efficiency still varies with weather and load. Compare COP figures only at the same test conditions and avoid using the highest advertised COP as an annual running cost assumption. Covering the pond and insulating appropriate pipework reduce the heat loss the pump must replace.

The published heating ambient range extends from −15°C to 43°C. This is an operating envelope, not a guarantee of any particular pond temperature at its lower limit. Use the controller settings and Wi-Fi functions in accordance with the manual, and make gradual changes when managing the temperature of a stocked pond.

Winter care and long term maintenance

Keep the heat exchanger fins and surrounding airflow clear, maintain filtration, and investigate flow warnings rather than repeatedly resetting them. If the heater is taken out of use during freezing conditions, drain it as directed in the manual. A winter capable heat pump still needs protection against water freezing inside an idle circuit. Electrical work and refrigerant service should be carried out by appropriately qualified personnel.

For smaller installations or a different air discharge arrangement, compare the other pond air source heat pumps. Contact us with your pond size, construction, intended winter temperature and available electrical supply so the selected Edge model can be matched to the actual installation.

Supplier pond size guidance

Thermotec gives a maximum pond volume guide of 11,600 gallons for this model. This does not state a guaranteed covered-pond 12°C winter capacity. Use the volume alongside the actual surface area, cover, insulation, location and desired temperature when selecting your heater.

Warranty and support

The published UK Thermotec Edge warranty provides three years of parts and labour cover on all components, with five years of cover on the compressor and heat exchanger. Warranty conditions apply, and damage caused by incorrect installation or freezing is excluded. Keep your purchase details and installation records, and contact us if you need help with a fault or a replacement part.

Installation manual

Read the Thermotec Edge installation manual before planning the water circuit, electrical connection and outdoor clearances. Keep the instructions supplied with your exact unit for installation, controller settings and maintenance.

Compare other Thermotec Edge models

Check the heating output, required water flow and electrical supply on each individual model before choosing. A larger nominal rating does not replace an assessment of your pond’s winter heat loss.

• Thermotec Edge 10.5kW single phase Inverter Pond Heat Pump
• Thermotec Edge 13.8kW single phase Inverter Pond Heat Pump
• Thermotec Edge 17kW single phase Inverter Pond Heat Pump
• Thermotec Edge 20.5kW single phase Inverter Pond Heat Pump
• Thermotec Edge 21.5kW three phase Inverter Pond Heat Pump
• Thermotec Edge 30kW single phase Inverter Pond Heat Pump
• Thermotec Edge 30kW three phase Inverter Pond Heat Pump