KSDB Drainback solar hot water heating systems
KSDB Drainback systems consist primarily of a water tank (11), a smaller tank that stores heat-transfer fluid (14), a solar panel array that collects heat from the Sun (3), and a heat transfer system that transfers heat to the water tank.
How a drainback works: A heat-transfer fluid only circulates through the system when the panels are collecting a usable amount of heat from the sun's rays. The heat transfer loop is only filled with the transfer fluid when the pump (13) operates. At other times such as at night, the pipe loop is full of air. When working properly, this configuration prevents the freezing of the heat transfer fluid.
advantages
- Easy to install. The KSDB series drainback module comes pre-assembled with pumps plumbed and controller mounted.
- Proven reliability. Can operate for years without owner intervention or maintenance. They "just work".
- Compatible with existing water heater. The KSDB can be connected directly to your present water-heater thus converting it to a solar-assisted water-heater.
- Built-in automatic, reliable freeze and overheat protection. All the water leaves the solar panels and weather exposed piping whenever the pump is not active --such as at night, when it is freezing cold during the day, or there is an electrical power outage.
- No anti-freeze used. No need to periodically flush and fill the system with expensive, new anti-freeze fluids.
sizing KSDB systems
For best results, systems should be matched according to energy use patterns and local installation conditions. If you are sizing a system for a residence or residential building, and you have:
- a location (such as roof) to install panels that has a clear view of the sun as it moves across the sky from near sunrise to sunset
- a way for all pipe between the drainback tank and the solar panels to have a slope of 0.25inch per horizontal foot or steeper
then, these recommendations optimize your overall cost savings for:
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A house, modular, manufactured, or mobile home:
- KSDB-32 Drainback System with one KS-32 4x8 collector for 2 or 3 people. The KSDB-32 may not qualify for some tax credit programs.
- KSDB-32-ST System a KSDB-32 and 80gal storage tank
- KSDB-40 Drainback System with one KS-40 4x10 collector, for 3 or 4 people
- KSDB-40-ST Drainback System a KSDB-40 and 80gal storage tank
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A duplex or 2 attached households and a shared water-heating system:
- KSDB-64 Drainback System with two KS-32 4x8 collectors, for 4 to 6 people
- KSDB-64-ST Drainback System a KSDB-64 and 80gal storage tank
- KSDB-80 Drainback System with two KS-40 4x10 collectors, for 6 to 8 people
- KSDB-80-ST Drainback System a KSDB-80 and 80gal storage tank
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A triplex or 3 attached households and a shared water-heating system:
- KSDB-80 Drainback System with two KS-40 4x10 collectors, for 6 to 8 people
- KSDB-80-ST Drainback System KSDB-80 and 80gal storage tank
- KSDB-96 Drainback System with three KS-32 4x8 collectors, for 7 to 9 people
- KSDB-96-ST Drainback System KSDB-96 and 80gal storage tank
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A quadplex or 4 attached households and a shared water-heating system:
- KSDB-96 Drainback System with three KS-32 4x8 collectors, for 7 to 9 people
- KSDB-96-ST Drainback System a KSDB-96 and 80gal storage tank
- KSDB-120 Drainback System with three KS-40 4x10 collectors, for 9 to 12 people
- KSDB-120-ST Drainback System a KSDB-120 and 120gal storage tank
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A 5-plex or 5 attached households and a shared water-heating system:
- KSDB-120 Drainback System with three KS-40 4x10 collectors, for 9 to 12 people
- KSDB-120-ST Drainback System a KSDB-120 and 120gal storage tank
- KSDB-128 Drainback System with four KS-32 4x8 collectors, for 8 to 12 people
- KSDB-128-ST Drainback System a KSDB-128 and 120gal storage tank
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A 6-plex or 6 attached households and a shared water-heating system:
- KSDB-160 Drainback System with four KS-40 4x10 collectors, for 12 to 16 people
- KSDB-160-ST Drainback System a KSDB-160 and 120gal storage tank
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A 7-plex or 7 attached households and a shared water-heating system:
- KSDB-160 Drainback System with four KS-40 4x10 collectors, for 12 to 16 people
- KSDB-160-ST Drainback System a KSDB-160 and 120gal storage tank
The optimal system for a 7-plex can be the same as for a 6-plex, because more than 3 people are served by each of the solar panels in this size of system, and the average occupancy* is about 2 people per unit.
*You can have confidence in these recommendations knowing that we use data about water-heating usage from the US Energy Information Administration (EIA), performance measurements of independent laboratory certifications of system components, and our decades of experience with solar water-heating installations and maintenance. In some cases, you may be able to increase savings by adding an additional solar panel.
other drainback systems
For custom designed systems, King Solar offers these Drainback system modules:
- DBHX1062 Solar Drainback DBHX Module - Drainback system module, 10 gallon DB tank with heat exchanger
- DBHX1598 Solar Drainback DBHX Module - Drainback system module, 15 gallon DB tank with heat exchanger
Both system modules require at least one solar water-heating collector and a few other components in addition to the module. See drainback systems (above) for lists of other commonly used components.
For best results, systems should be matched according to hot-water use patterns and installation environmental conditions. Sizing a commercial solar system can be a challenging exercise, regardless of system type. The best thing to do is send us your requirements.
Tell us:
- how the solar hot water heating system will be used. For example, will it be used in a home or as part of a boiler system in a commercial environment
- how many gallons of hot water are used per day. We can approximate by knowing how many people live in the residence, or how much heat is created per day by a boiler etc.
Contact us for a price quote. We will reply within 48 hours with a suggested set of equipment specifications to meet your alternative energy needs.
