http://www.sentry-equip.com/Public/BrochuresandDataShee/DTC17.1.pdf

http://www.thomasnet.com/products/heat-exchangers-spiral-tube-95928214-1.html

• Presentation:
• Intro: who it will serve
• Objective
• Why it’s important
• Current designs
• Concepts: Internal vs. external heat exchanger
• Internal options
• External options
• Decision matrix
• Choose 1 of each
• Sub components: pump, refrigerant and sensor
• Cost analysis

Need concept generation
            Six different design concepts

Internal heat exchangers:

• U tube
• T-joint
• Advantage: easy to thread thru T-joint and tank
• Disadvantage: no Connection made for T-joint fitting
• How to make water tight? Sealing options
• Not as efficient: relying on natural convection inside tank
• Can compressor push all fluid down and back through tube?
• Refilling R-22: installation cost
• U-Tube
• T-joint: In cold, out hot
• Advantage: fitting onto T-joint is available
• Don’t have to worry about making water tight
• Disadvantage would be harder to thread through the tank
• Not as efficient: relying on natural convection
• Can compressor push all fluid down and back through tube
• Refilling R-22: instillation cost
• In top, down through tank, out bottom element
• T-Joint
• Advantage: fitting onto T-joint is available
• Advantage: Easy to thread thru T-joint and tank
• Lose surface area of heat exchanger - Bad
• Less efficient based on less surface area and natural convection
• Can compressor push all fluid down and back through tube
• Refilling R-22: instillation cost

External Heat exchanger

• Enclosed window unit condenser to use as heat exchanger
• Use existing condenser
• Advantage: No refilling of R-22
• Have to encase the condenser: material, design
• Spacing would be challenging
• Connections through the wall without cutting the condenser pipes
• More efficient: forced convection
• Pump, adds money and uses electricity

• Coaxial coil heat exchanger (ordered)
• Cost!!!!! Could be expensive
• Very efficient and effective based on design
• Connections would be easy, parts available
• Pump and electricity

• Flat Plate Heat exchanger
• Cost, cheaper than coaxial
• Too complicated to build
• Have to custom order
• Size may not be available
• Don’t have as much info!

Thermostat:

            Separate from heat exchanger

• Use existing thermostat on hot water heater to control AC unit
• Use a different thermostat and hook up to Ac unit and water tank

Pump:
Once the flow and head requirements are calculated, an appropriate pump can be selected.  Based on as

• Basic Aquarium pumps
• Between 250-950gal/hr
• Between 40$ - 80$

Mounting: same in every case, essentially

AC unit and water heater are the same for every design.

Leaky coils are a losing proposition, because they are the beginning of the end of efficient heat transfer. Although coils may fail for a variety of reasons, mechanical failure and corrosion are the culprits in the majority of cases. When coils corrode, unwanted moisture and contaminants may foul the air stream or exhaust gases. And a steam leak from a badly corroded coil simply blows precious energy off into the atmosphere