Why winter is the hard season for hotel hot water
For most hotels, hot water is not an extra. Guests expect it at any hour, in any weather. Fiidotherm’s own notes on hotels make the point plainly: hotels need hot water 24 hours a day, 365 days a year, whether it is cloudy, rainy or winter.
Winter adds pressure from several sides at once. In many tourist destinations it is the busy season, so more rooms are occupied. Showers get longer and hotter. Laundry, spa and pool loads go up. When the heating method is LPG, the fuel bill rises in step with all of that, because every extra litre of hot water means more gas burned.
Solar water heaters are the usual first idea, and the Sudarshan Saur group behind Fiidotherm has made them since 1989. But Fiidotherm’s FAQ is candid that in foggy winters and in places with weak winter sunshine, a solar-only system struggles. That gap is where a heat pump is worth a look.
How each one makes hot water
LPG water heater: Gas is burned, the flame heats the water. The cost depends on how much gas you burn, and you need cylinders or a gas storage arrangement on site.
Heat pump water heater: Fiidotherm describes its Low Energy Water Heater (LEWH) as a “reverse air conditioner”: the same refrigeration cycle as an air conditioner, used for heating instead of cooling. It collects heat from the air and transfers it to the water. Because most of the heat comes from the air, the electricity needed is comparatively small.
The measure for this is COP (coefficient of performance). As Fiidotherm’s FAQ explains it, a COP of 4 means that for every 1 kW of electricity going in, about 4 kW of heat comes out as hot water.
The honest winter question: what happens to a heat pump when it gets cold?
This is where good content usually goes quiet, so let’s be direct. Heat pump efficiency falls as the air gets colder. Fiidotherm’s FAQ says COP is generally 4 to 5 when the outside temperature is around 20°C, and drops to around 2.5 when it reaches 0°C. It is also higher when the gap between the two fluids exchanging heat is smaller.
The FAQ also notes that in freezing conditions the unit runs a defrost cycle to clear ice from the outdoor unit, and heating pauses for short periods while it does.
What this means for a hotel: a property in a mild-winter city and a property in a hill town are not the same case. The heat pump still works in both, but the savings story, the number of units and the amount of storage should be worked out for your actual winter temperatures. A sizing check before purchase is not a sales formality here; it is the part that decides whether the numbers hold.
LPG and heat pump side by side
|
LPG water heating |
Heat pump water heating |
| How heat is made |
Gas is burned |
Heat is moved from the air to the water using a compressor |
| What you mainly pay for |
Gas |
Electricity (mainly to run the compressor) |
| Fuel storage for water heating |
Cylinders or gas storage on site |
None needed for the water heating itself (kitchens may still use gas) |
| Open flame at the heater |
Yes |
No combustion at the heat pump |
| Effect of cold weather |
Does not depend on air temperature |
Efficiency falls as air gets colder (COP about 4 to 5 at 20°C, about 2.5 at 0°C, per Fiidotherm FAQ) |
| Space |
Varies by installation |
Fiidotherm says minimal space; units can also sit indoors or at ground level, not only on the terrace |
| Routine upkeep |
Gas supply, burners and safety checks |
Yearly or half-yearly inspection of pressure and shut-off valves, strainer, control box, fins and fan |
How a hotel can check its own numbers
We are not going to quote a savings percentage here. Savings depend on your tariff, your LPG price, your climate and your usage, and no single number fits all hotels. What we can give you is a simple way to build your own comparison from your own bills.
- Separate the water-heating gas from the kitchen gas. Ask your supplier or accounts team for last winter’s LPG consumption, and estimate how much of it went to hot water.
- Estimate the heat you need. As a rule of thumb from basic physics, heating 1 litre of water by 1°C takes about 1.16 watt-hours. Multiply by litres per day and by the temperature rise you need.
- Divide by a realistic COP. Electricity needed is roughly the heat needed divided by the COP. Use the cold-month COP, not the best-case figure.
- Multiply by your electricity tariff, then set the result against your LPG cost for the same hot water.
This is a rough screening method, not a quotation. A proper design adds storage losses, piping, peak demand and standby capacity. That is what a site sizing does.
Practical points to settle before you decide
Fiidotherm’s FAQ lists several installation precautions. They are worth knowing early, because they shape where the plant goes:
- Ventilation. Install the unit where there is enough airflow.
- Electrical supply. Place it near the electrical connection, single or three phase as recommended, and use a voltage stabiliser if your area has heavy fluctuation.
- Water quality. If water is hard, above 300 ppm, use a softener at the inlet. A strainer or filter helps prevent the heat exchanger from choking.
- Shade. Preferably install the unit and controller under shade so leaves and debris do not clog the fins and fan.
- Running hours. Fiidotherm advises against running the unit 24 hours a day, which shortens its life. The FAQ suggests around 8 hours of running, used as required. For a hotel, that is why the storage tank and sizing matter as much as the heat pump itself.
Where Fiidotherm fits
Fiidotherm is a manufacturer of heat pump water heaters in India, a sister concern of Sudarshan Saur Shakti Pvt. Ltd., which has designed, manufactured and marketed solar water heaters since 1989. The manufacturing unit is at MIDC Waluj in Chh. Sambhajinagar, Maharashtra. For hotels, the relevant products are the commercial heat pump for guest rooms, kitchens and laundry, and the swimming pool heat pump where the property also has a pool. You can read more in our FAQ.
Frequently asked questions
Is a heat pump better than LPG for a hotel?
It depends on your climate, tariff and usage. A heat pump moves heat from the air instead of burning fuel, and Fiidotherm’s FAQ says it is four to five times as efficient as electric heaters, boilers and oil or diesel-fired equipment. Whether that turns into lower bills for your hotel is best checked with a sizing based on your own consumption.
Does a heat pump water heater work in winter?
Yes, but efficiency falls as the air gets colder. According to Fiidotherm’s FAQ, COP is around 4 to 5 at 20°C and around 2.5 at 0°C, and the unit runs a defrost cycle in freezing conditions. The system should be sized for your coldest month.
Can a heat pump replace LPG completely in a hotel?
For water heating, a properly sized heat pump system can take over the load that LPG heaters carry today. Kitchens that cook on gas are a separate matter. Some hotels may also choose to keep a backup source; that is a design decision to make with your consultant.
Can one system handle both guest rooms and the swimming pool?
Fiidotherm’s commercial heat pump is described as suitable for guest accommodation, spa facilities and resort pools, and it also makes a dedicated swimming pool heat pump. Which combination suits your property depends on loads and layout, so ask for a sizing.
What does a hotel need to share to get a sizing?
Number of rooms, city, current hot water source, approximate daily hot water use if known, available space for the outdoor unit, and whether the hotel has a pool, spa or laundry.