Passive Solar Water Heater


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150 Liter Standard Passive Duda Solar Water Heater Attached...
  • Hailstone Resistance: up to φmm (1"), Max Operating Pressure: 100psi, TK-7Y Controller
  • Painted Zinc Outer Shell & Stand, Pressurize tank for domestic water supply, 14mm TU1 Copper Heat Pipes, Winter...
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Passive solar water heaters are an efficient and cost-effective way to heat water using the sun’s energy. They work by capturing the sun’s rays in a solar collector, usually a flat-plate collector, which is then used to heat up the water in a storage tank. The heated water is then circulated through the home’s water system. Passive solar water heating systems do not require any active components such as pumps or controllers, making them much simpler and more reliable than active solar water heating systems. To ensure maximum efficiency, passive solar hot water systems should be well insulated and placed in an area that receives direct sunlight for most of the day. By taking advantage of the sun’s free energy, passive solar water heaters can provide hot water for your home at a fraction of the cost of traditional electric or gas-powered systems.

These systems can be a great way to save money on your heating bills. They work by using the sun’s energy to heat up water, rather than relying on conventional water heaters. Unlike active solar water heaters, which use pumps and controllers to move the heated water around, passive systems are typically simpler and more cost-effective. They also require less maintenance than active systems. Passive solar water heaters come in two main types: glazed and unglazed collectors. Glazed collectors are usually more efficient at collecting and storing solar thermal energy, while unglazed collectors are better for areas with high humidity or temperatures. Solar storage tanks are also used in some systems to store the heated water until it is needed. With a passive solar water heater, you can save money on your heating bills while helping the environment at the same time.

When you’re trying to choose a solar water heater passive may be the way to go. Passive heaters are a great solution for places where the climate doesn’t get too cold, even in the winter. They’re also good for households that don’t use as much warm water at night as they do during the day.

There are two types of passive heaters, but they both function more or less the same way. Learn more about what makes up a passive solar water heater system below.

How Does It Work?

In this section, you’ll find information about how a passive heater works to heat your water. You’ll also learn more about its strengths and weaknesses as well.

How does it heat water?

  • A passive solar heater collects heat from the sun through a solar panel and uses that heat to warm the water inside. From there, the water moves to a collection tank where it stays until it’s ready for the household to use it. Neither type of passive solar heater requires a pump in order to work.

What are its main components?

  • Collection: This part of the heater is contained inside the solar panel and holds water while it’s being heated.
  • Storage: This tank holds the hot water after it’s been heated.
  • Water inlet and outlet: These pipes move water from the house to the heater and back again as needed.

How effective is it?

  • These types of heaters are quite effective in places with a lot of direct sunlight. They get the job done and don’t use extra energy for pumps to do it. They work best during the day.

How efficient is it?

  • This type of heater is not as efficient as the active type. It takes a while for water to heat up in a passive heater, and it may sometimes need to be used in conjunction with a more traditional type of “backup” water heating system inside the house.

What are some of its pros?

  • This is usually a less expensive type of water heating system, both to set up and to maintain.
  • A passive system is a great choice for smaller households or families that simply don’t need as much hot water as others.
  • Passive systems work great in warmer climates and can help people in these areas live greener and more energy-efficient lifestyles.

What are some of its cons?

  • Those who live in cold climates may have to worry about their pipes freezing when using a passive system.
  • Some roofs may not be stable enough to support the weight of a water tank plus a solar panel.
  • Stored water may cool off quickly in a passive system, especially in certain locations.

Setup and Maintenance

Look through this section to find out more about what it takes to set up and maintain your passive heater.

How do you install it?

  • A passive solar water heater has to be installed entirely on the roof. This is because water flows downward from the collection tank to the house, without the use of pumps. The solar panel, pipes, and tank all sit on the roof, and inlet and outlet lines are connected to the house’s water supply.

How do you maintain it?

  • Clean the solar panel appropriately several times throughout the year.
  • Frequently check the plumbing and tank to ensure there are no cracks.
  • Check often throughout the year to see how much sun versus shade the heater is getting.
  • Have a professional inspect your roof regularly to make sure the weight is not causing a problem.
  • If you notice a lot of buildup related to hard water on your water heater system, you’ll need to use a water softener for your home as well.

How much does it cost to set up and maintain?

  • Passive solar heaters are very low-cost in comparison to active ones. They generally come in well under budget for people who are looking to make energy-efficient changes in their households. Passive heaters tend to be less than half the cost of active ones.
  • Maintaining your passive heater doesn’t cost too much, but regular roof inspections are a cost to consider.
  • Remember that you will be saving a lot of money on your energy bill when you don’t need gas or electricity to heat your water, so the cost may be negligible in the long run.

Do you need to purchase additional components for installation?

  • Not usually. Most solar heaters will come with everything you need to install them. However, it’s important to read the fine print on any heater you’re thinking of installing to make sure it has everything you need.
  • Some heaters may require you to purchase a backup heater tank in addition to the cost of the solar heater itself.


So what do you think? How do you know whether or not a solar passive water heater is right for you? Is there really a good way to tell?

The most important thing to consider when choosing the right type of solar water heater for your home is the climate where you live. If you see a lot of days below freezing or without much sunlight, then you should go with an active heater that can prevent itself (and your pipes) from freezing. These heaters can also store more hot water for use later in the day.

A passive heater, however, is great for warm climates or places with plenty of direct sunlight. They usually heat water as needed or store a small amount of hot water for later use, so they’re ideal for people who use their hot water more while the sun is up and less at night. This type of heater is also good for anyone who wants to keep the heater entirely on the roof.

If you’re thinking of trying a passive heater, check out this option below. This is a good place to get started using a passive heater for your home, and it can help you make the move to greener living, too.

Duda Solar 150 Liter Standard Passive Water Heater

150 Liter Standard Passive Duda Solar Water Heater Attached...

The Duda Solar 150 Liter Standard Passive Water Heater  is a great starter water heater for nay household. The heater includes 15 solar energy tubes, which work to heat the water inside without the need for a separate panel. From there, it moves into the house’s plumbing without the use of a pump.


  • The heater comes with a tank, solar heating tubes, a controller, and an electrical backup heater.
  • This heater can be programmed to only heat at times of the day when it’s needed.


  • This option may be difficult to install, especially for beginners.
  • The heater is bright blue and may not be approved by all HOAs.


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Last update on 2024-02-26 at 19:57 Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.

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