A hot tub in the yard: how to heat the water
There are three ways to heat the water: gas (quick and inexpensive), an electric heat pump (keeps the water hot all day) or an open fire (atmosphere). The choice depends on how much you host and how soon you want to get in.
The Israeli climate gives us a relatively mild winter: one that lets us soak in pleasant water under the open sky, host friends for a winter party with a twist, and unwind in the open air before bed.
The containers can be connected to a pump that passes the water through a heater running on gas, electricity or a live fire.
Over the years our customers have turned the containers into striking indoor baths by planning the plumbing in advance, as Becky did: she planned a bath for her five children at home, 2.46 m long, 80 cm wide and 60 cm high.
Anyone who lives in a rented home and wants a bath can use a metal container (1.26 m long, for example) and add a drain tap in the side wall to empty the water easily. The containers are not heavy (15-25 kg), so they can be moved when needed, into storage or onto the balcony.
Three ways to heat
Heating with a gas systemSafety
The least expensive and most convenient way is gas. The system is based on a caravan water heater (5 litres) fed by an 80 PSI pressure pump, which sends water to the heater and from there to the container.
Heating time depends on the water and outdoor temperatures and runs from 60 to 90 minutes. The heater and pump can be bought from us with a one-year importer's warranty; in parallel, contact a licensed gas technician for installation and to order gas cylinders.
Heating with an electric heat pump
To heat the hot tub in the way closest to public hospitality venues, we recommend installing a heat pump only.
It also needs a cleaning pump that draws the water, cleans it and sends it on to the heat pump.
The pump is a significant purchase (₪3,000-7,000), but with a regulator and a timer it can keep the water hot for most of the day.
Heating with an open fire
A way of heating common in cold countries is a campfire or a stove. We recommend a stove with a chimney, to avoid smoke while you soak. Guests enjoy the warmth around them, and the fire is mesmerising and makes for a memorable time around a retro stove.
Heating the water takes about two hours (for a 1.5 m container). Inside the stove a maze of half-inch iron pipes is built, separated by a simple metal profile to prevent wear.
Use a pump of at least 1,400 gallons to send water to the stove.
A quick comparison
| Way of heating | Heating time | Cost | Best for |
|---|---|---|---|
| Gas | 60-90 minutes | The least expensive | Private use, couples |
| Electric heat pump | 24-48 hours, then keeps the water hot all day | ₪3,000-7,000 for the pump | Those who host friends and events often |
| Open fire (stove) | About two hours for a 1.5 m container | - | Atmosphere and warmth around the fire |
Questions and answers
Metal with water and cleaning agents: does it not rust?
Retro containers are in fact stock tanks (for feeding and watering animals), a design that has existed for over a century, made for us today in China. They are meant to stand outside, in the sun and full of water, for a very long time.
After a few years we recommend a controlled epoxy coating, to give the container a renewed protective layer.
Hosting, or soaking alone?
When choosing how to heat, consider the time needed before you can get into the water.
A gas or fire heater works faster and brings the water to the temperature you want in one to two hours.
The electric heater heats the water more slowly (24-48 hours), but it has a thermostat that keeps the water hot all day.
The type of heater depends on how you use the tub: for private use and couples a gas water heater is enough; for those who host many friends and events, an electric heating system is recommended.
Where you live: is insulation needed?
Because the containers are made of metal 1 mm thick and have no added insulation, in places such as the Golan Heights, the Jerusalem hills and Samaria we recommend adding a layer of insulation to the container; otherwise a good deal of heat is lost and more energy is needed to heat the water.
The containers for this
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