What it is
Think of an aircon that heats water instead of cooling a room. A small compressor pulls heat out of the air around the unit and pushes it into an insulated tank. The air gives up its heat for free; you pay only to run the compressor. That is why ₱1 of electricity turns into about ₱4 of hot water, where an electric shower gives you ₱1 for ₱1.
Karnot's version is the AquaHERO: an all-in-one unit with the heat pump built onto the top of the tank, using R290 refrigerant, made for warm climates.
Which size do you need?
Size by how much hot water you use in a day, not by the size of the house.
| Your situation | Size | What it does |
|---|---|---|
| House, villa or condo — one or two bathrooms | AquaHERO 200 L | Makes about 54 litres of hot water an hour and stores 200 litres. Enough for a family's showers, kitchen and laundry. |
| Clinic, salon, B&B, guest house — around 400 to 600 litres a day | AquaHERO 288 L | About 65 litres an hour, 288 litres stored. Keeps up with a morning rush of guests or patients. |
| Café or restaurant that also wants solar power | iVOLT F&B kit | Solar, battery and an AquaHERO in one installed price of ₱370,000. |
| Hotel, laundry, food plant — above about 600 litres a day | iHEAT commercial heat pump | 9.5 to 100 kW, sized to a measured load, feeding a separate tank farm. |
Not sure? Count your bathrooms and think about the busiest hour of the day. One or two bathrooms is the 200 L. If people queue for showers, it is the 288 L. If you run a business past that, a free survey measures it.
What it saves
| Your hot water bill today | With a heat pump water heater | Saved in a year |
|---|---|---|
| ₱2,000 a month | about ₱500 | about ₱18,000 |
| ₱4,000 a month | about ₱1,000 | about ₱36,000 |
| ₱8,000 a month | about ₱2,000 | about ₱72,000 |
Measured, not modelled: a Philippine guest house that replaced its per-bathroom electric showers with one AquaHERO saves about ₱53,000 a year, and paid the unit off in under four years.
The honest catch: the saving comes from daily use. A bathroom used once a week does not justify the machine, and an electric shower is the right buy there. We will tell you which side of the line you are on.
What it costs
Each AquaHERO is quoted to your bathrooms and daily usage, installed. Send us a photo of your electricity bill and the number of bathrooms and you have a firm price within a day. It costs more than an electric shower on day one and about a quarter as much to run every month after — the comparison is set out fairly in heat pump vs electric water heater.
Every unit carries a 24-month warranty from delivery.
What changes in your house
- One unit replaces every electric shower. The hot water runs to the existing pipes. The electric showers come out, or stay as a backup if you prefer.
- It stands indoors — a garage, utility room or covered service area — with about 600 mm of space around it and 2 m above. The 200 L unit is 57 cm across and 1.8 m tall.
- It needs a standard 13 A socket. No new circuit. The 200 L draws at most 9 A.
- It needs air. Two 600 mm ducts bring air in and take cooled air out. That cooled air can go into the room if you want it — a laundry room stays a few degrees cooler as a side effect.
- It needs a drain. The unit pulls moisture out of the air as it works, like an aircon, so a small condensate pipe runs to waste.
- Hot water is stored, so brownouts do not matter. The tank already holds a full day's hot water.
- It is quiet. About 55 dB(A) — a normal conversation.
Two things people worry about
Is it hot enough? Yes. The heat pump alone reaches 65 °C, hotter than any shower needs; a built-in 1.5 kW backup element can take it to 75 °C if you ever want it.
Is the propane refrigerant safe? R290 is propane, in a sealed charge of 150 grams — less than a camping-stove canister — inside a unit designed to the European EN 378 safety standard. It is never refilled by the customer.
Questions we get asked
What is a heat pump water heater?
A hot water tank with a small heat pump on top. It makes the same hot water as an electric heater for about a quarter of the electricity, and plugs into a standard 13 A socket.
How much does it cost in the Philippines?
Quoted to your bathrooms and usage, installed. Send a photo of your bill and the number of bathrooms and you have a firm price within a day.
Which size do I need?
One or two bathrooms: 200 L. Around 400–600 litres a day: 288 L. Above that: a commercial iHEAT.
What does it need to be installed?
A 13 A socket, an indoor spot with a little clearance, a condensate drain and two 600 mm air ducts. Cold in, hot out to your existing pipes.
Does it work at night and in a brownout?
Around the clock — the fuel is the heat in the air. In a brownout the tank already holds hot water.
Is the propane refrigerant safe?
150 grams, sealed for life, EN 378 design. Never refilled by the customer.
Get a price for your house
Send us a photo of your electricity bill and tell us how many bathrooms you have. You get a firm installed price within a day. If an electric shower is honestly your better buy, we will say so.
Send us your billRelated: AquaHERO 200 L · AquaHERO 288 L · Heat pump vs electric water heater · Heat pumps in the Philippines · Commercial hot water in detail