Chat with Sunniva on WhatsApp
Skip to Content
Sizing tools

What are you heating?

Six tools. The first five select a machine from Sunniva’s own published performance data — every capacity and COP comes off the datasheet of the machine being recommended, interpolated to your conditions. The sixth is for a machine that does not exist yet: it works out the duty the same way, then records what you need built. All six give you the kilowatts, what it costs to run against what you burn today, and a sheet you can save.

Swimming pools

A swimming pool

26 – 32 °C

Indoor or outdoor, covered or open. Sized on the real surface losses — evaporation, convection and radiation — not on a litres-per-kW rule of thumb.

  • Heat-up time and holding load, separately
  • What a cover is worth, in rupees
  • Live section drawing of your pool
Size it now →
Hot water, 1,000 – 100,000 litres a day

Hot water for a building

40 – 70 °C

Hotels, hospitals, hostels, canteens, laundries. Pick the building type and set the occupancy, or enter your litres a day directly.

  • Storage tank sized alongside the machine
  • EVI selected automatically when the winter needs it
  • One machine or several, with an optional standby
Size it now →
Space heating

Warming a building

35 – 60 °C water

Rooms, floors or whole buildings. And — unusually — the fan coils or radiant panels that actually put the heat in, which is what decides whether the building is warm.

  • Fabric and ventilation heat loss from your construction
  • Fan coils sized in tons, panels on the EN 442 curve
  • Shows how much panel output survives on heat pump water
Size it now →
Industrial process heat

An industrial process

up to 80 °C

Plating lines, CIP sets, jacketed reactors, dyehouses — or your own duty, entered directly. One tool, and it changes to match the application you pick.

  • Seven-tank plating, CIP, jacketed tanks, textile dyeing
  • Tells you whether your jacket has the heat transfer area
  • Waste heat recovery, which usually shrinks the machine
Size it now →
Geothermal · ground source

A ground loop

any duty

The one tool here that sizes the ground rather than the machine: metres of bore, number of holes, land needed — or flow, if an open well suits the site better.

  • Bore field, trench field or open well, in their own units
  • Works out the long-term ground balance, which most tools skip
  • Compares against VRF, air-cooled or water-cooled chiller
Size it now →
Customized · engineered to order

Something the catalogue does not have

any duty, to 120 °C

A duty above the standard range, a water that would eat an ordinary exchanger, an ambient nobody designs for, or a refrigerant your reporting position requires.

  • Works out the duty, then records the build you want
  • Flags a refrigerant that will not reach your temperature
  • Arrives with our engineers as a complete enquiry
Size it now →

Or start from the temperature you need

If you already know the number, it decides the tool — and whether a heat pump can do it at all.

Above 80 °C you get two answers, not a dead end. The industrial calculator sizes the SE-HT range as a pre-heater with your existing boiler taking the last stretch — the easiest retrofit there is — and, below that, a machine that takes the whole lift and removes the boiler: SE-SHT to 95 °C, SE-UHT to 120 °C as a cascade from air or a single cycle from waste heat. Past 120 °C, or outside the standard build in any other way, the customized configurator is the one to use.

Every calculator is indicative and says so. They exist to get you to the right order of magnitude and the right machine before anyone picks up a phone — draw-off pattern, pipe runs, site conditions and local code all affect the final selection, and Sunniva Encon LLP confirms it before anything is ordered.

© 2026 Sunniva Encon LLP. The design and code of this page are our copyright. Results are indicative and offered in good faith — the method is set out above. Confirm the final selection with us before ordering.