Commercial and institutional buildings are generally characterized by frequent and high volume usage of hot water that is literally poured down the drain. The ThermoDrain is designed to recover this wasted energy and transfer it directly back into your potable water heating system thereby significantly reducing the costs associated with hot water heating.
Our dual wall construction heat exchanger is code approved for use with potable water.
Dishwasher Savings Scenario
Through the use of ThermoDrain, The end result is a reduction in hot water load vary from 32% to 45%.
Without ThermoDrain: We start with 100 units of gas, 20 units are lost to water heater exhaust, 80 unit are used by the dishwasher
With ThermoDrain: Energy required 40 units, 80 units are used by the dishwasher, (30 are supplied by the water heater and 50 is supplied by the ThermoDrain)
Laundry Savings Scenario
High maintenance heat exchangers with filtration systems have been used for heat recovery in laundry systems. The ThermoDrain does not require maintenance and solids can flow freely through the ThermoDrain without the risk of blockage. Savings expected is 35%, ROI is 2-5 years.
On slab construction
In the case where slab on grade construction or where the drain flow is in the floor, the drain water must be elevated using a pump. Electrical consumption for pumping drain water is 1-2% of the ThermoDrain energy savings. This type of system is difficult but not impossible to retrofit.
Sport center ganged showers scenario
A sport center having 16 showers is operating at a combined total of 100 hours of shower time per week. Low flow shower heads of 1.6 gpm operate at a shower temperature of 39°C (102°F). The natural gas heater is 78% efficient. The annual energy that is wasted down the drain is 272 GJ from the showers alone.
The potential for drain water heat energy recovery is calculated based on preheating the cold water going to the water heater using 4 ThermoDrain units. At an estimated 0.46$ per m3, the energy cost saving is 1905$/year with a 3.4 year payback.
A hotel with 80 rooms is occupied at 70%. The average shower time per room is 20 minutes per day and standard flow shower heads are used at a shower temperature of 39°C (102°F). The natural gas heater is 78% efficient. The annual energy that is wasted down the drain is 583 GJ from the showers alone.
The potential for drain water heat energy recovery is calculated based on preheating the cold water going to the shower using one ThermoDrain unit for two adjacent rooms. At an estimated 0.46$ per m3, the energy cost saving is 2654$/year with a 6.8 year payback.
Affordable housing complex with central heating scenario
A building having 24 housing units has central water heating. Three drain stacks service two units per floor each. Given the total shower time for each unit is 30 minutes per day and standard flow shower heads are used at a shower temperature of 39°C (102°F). The natural gas heater is 78% efficient. The annual energy that is wasted down the drain is 281 GJ from the showers alone.
The potential for drain water heat energy recovery is calculated based on preheating the cold water going to the water heater using two ThermoDrain unit per drain stack. At an estimated 0.46$ per m3, the energy cost saving is 1519$/year with a 3 year payback.
The installation of a ThermoDrain is a simple, proven and efficient measure that will contribute in obtaining credits associated with energy efficient LEED projects. Several LEED projects are presently using ThermoDrain technology to reduce the energy required to heat water.
The recovery of energy from drain water has obvious economical and environmental benefits but other advantages beyond these considerations exist. A building that incorporates ThermoDrain units as part of its hot water heating system will see a decrease in heating power requirements or in the size of the heating apparatus by recovering the energy that would have otherwise been sent down the drain. This is even more advantageous when less efficient hot water heating equipment is in use.
Many independent organizations have tested and recognized the efficiency of the ThermoDrain technology including National Resources Canada, the Canadian National Research Centre the Canadian Housing and Mortgage Corporation, Saskatchewan Research Council, Hydro Quebec and the US Department of Energy.
In order to comply with most plumbing codes in the US and Canada, we build our products with certified components. The components used in building the ThermoDrain have the following certifications. Our product is certified to used to preheat or precool potable water.
The ThermoDrain is made up of 3rd party ASTM certified copper drain tubing and is considered maintenance free thus retaining its efficiency over time. The ThermoDrain drain tube is the same diameter as the standard copper drain tube and will drain in the same manner with no restriction in the drain flow.
In essence, the longer the ThermoDrain, the more drain surface is available for heat transfer to occur. The same rule applies to the drain diameter, the larger the diameter, the more energy can be recovered.
Do not base your selection criteria solely on the efficiency of the units. Several other factors come into play when selecting a model. Drain water type, drain and potable water flow rate and temperature, unit pressure drop, are some of the parameters that need consideration when selecting a unit. Connection mode and configuration also impact the selection process.
Table no.1 provides a list of common models along with technical specifications. For help with selecting the proper model for your application please contact a technical representative at EcoInnovation.
Health and safety is a priority to us. EcoInnovation uses only certified copper tubing that is nationally recognized for use with potable water. To that effect, our potable copper tubing conforms to standard ASTM B88. The center drain tube conforms to ASTM 306. All soldered fittings conform to standards ASME/ANSI B16.23 or B16.29. This provides peace of mind in all applications.
The ThermoDrain drain water heat recovery unit is composed of a copper drain section around which a copper pipe is moulded and wound. As hot water drains down the central copper pipe, an important heat transfer occurs thereby preheating the cold water circulating in the outer coil. This incoming cold water may be preheated by more than 18 degrees Celsius (32 degrees F) before entering the water heater.
What makes the ThermoDrain so unique is that it is the only style of heat exchanger that is allowed to be used for potable water due to its double wall leak-proof design.
The ThermoDrain is the only drain water heat recovery unit that has a very low-pressure drop through the use of a single 3/4″ coil. Other manufacture designs require splitting of the flow into 1/2″ or 3/8″ thin walled channels and headers. Designs that do not improve performance but may impact longevity of the unit.
ThermoDrain’s is constructed using potable copper tubing with walls that are 0.045″ thick and a 0.75″ in diameter.
ThermoDrain drain water heat recovery exclusive PEX fittings
The ThermoDrain does not have restrictions such as fins inside of the drain pipe.
The ThermoDrain heat exchanger works under the principle of gravity film exchange. Due to the superficial tension present in liquids, the wastewater clings in a film-like fashion to the inside wall of the drain pipe as it undergoes gravity flow in the open drain. This greatly improves the effectiveness of heat transfer from the falling drain water to the water inside the copper coils that winds around the central pipe. The heat exchange is thus completed with no contamination risk to the incoming cold water.
A superficial film forms on the interior wall of the ThermoDrain as hot waste water transfers its heat energy to the copper drain tube.
6 ThermoDrain TD480A3 series being used in a commercial laundry