How tankless water heaters work
Tankless water heaters also known as on-demand, or instantaneous have been around for decades, but have had limited market penetration in the United States. In other parts of the World where energy costs are higher and space is limited, these tankless water heaters are the standard. Tankless water heaters use a different heating system than the storage tanks type water heaters found in most homes today. Tankless water heaters are more efficient and can generate a continuous supply of hot water. Because of the flow through, on-demand system, your hot water faucet or appliance becomes the trigger that will activate this type of water heater. FLASH
The Flash water heater, model T-K1, is an on-demand, tankless gas water heater. This space saving, highly energy efficient water heater can deliver over 200 gallons of hot water per hour and since there is no tank to run out, you get an ENDLESS supply of hot water.
The Flash utilizes the latest in technological controls for efficient water heating. These include computer modulated gas valves, electronic temperature sensor, electronic water flow sensor, electronic ignition (no pilot burner), computerized safety devices and even pipe heaters to protect the unit when the temperature is near freezing. Because of these advance controls the Flash is compact, about the size of a small Pullman suitcase, yet 5 times more powerful than the average storage tank water heater. The Flash has a self modulating input rating of 37,000 to 165,000 Btu.
The Flash with its durable design and rust resistant powdered coating is made to be installed outdoors also.
[Top] How the Flash Operates
The T-K1 only bums gas when you need hot water.
1) Open a hot water faucet.
2) When the flow rate exceed 0.75 GPM the computer electronically ignites the powerful stainless steel burner.
3) Then the computer measures water temperature, flow rate, and adjusts the gas valves so you maintain the 140*F outlet hot water temperature.
[Top] With a storage tank, you store 40-75 gallons of hot 140*F water 24 hours a day, 7 days a week though you only use hot water a couple times a day. The tank type heaters constantly lose heat through the flue and tank walls trying to maintain 140*F. The heater cycles on and off to maintain this temperature. This causes cracking of the exterior walls and sediment build up which will eventually cause your storage tank to leak. The storage tank is designed to wear out and be replaced in time. Also, the storage tank water heaters only have a limited amount of hot water and after that is gone you have to wait for the tank to get heated again.
The Flash heats the water only when there is a demand for hot water. Opening a hot water faucet, ignites the powerful burners and the computer monitors the water temperature and adjusts the burners according to the need. High demand, high heat. Low demand, low heat. With no tank to run out you get an endless supply of hot water. No tank to heat means no standby heat loss. The Flash provides a continuous flow of hot water and will never run out, but the flow rate is limited to the temperature that you set. With a self modulating input rating of 37,000 to 165,000 Btu's this unit can handle a small application like a bathroom faucet and can take care of large demand application like a washing machine or dishwasher. This heater is designed to give you the maximum amount of hot water. With the 140*F temperature setting, you will need to mix it with cold water to get the water temperature you desire.
Household Flow Rates
Flow Rates of T-K1
Base on hot water outlet temperature 140 F
GAS PIPING [Top]
The Flash is more efficient than normal storage tank type water heaters and save energy. However the Flash requires more Btu's to heat water instantly. This means the Flash burns a lot of gas for shorter periods and only when you require hot water. Normal storage tanks burn at a gradual rate because it has plenty of time through the day to keep your 30-75 gallons of hot water stored and it will cycle on and off to maintain this temperature.
To get the most out of your Flash water heater, make sure you size the gas piping accordingly. The Flash will work more efficiently when it has an adequate supply of gas. Follow the National Fuel Gas Code or your local building codes to size the gas pipe
The Flash comes with an automatic adjusting pressure regulator which has been set at the factory and should not be adjusted. The computer modulates the gas valves so you can maximize the use of your Flash. This unit is designed for one type of gas only. Make sure you have the right type for your installation.
Data from the National Fuel Gas Code.
All water connections are 3/4". Make sure you correctly attach the hot and cold lines. If you reverse connections on this heater, it may cause a dangerous situation. Use approved connectors when installing so replacement and maintenance can be done with ease. Allow adequate space on the piping side for maintenance.
[Top] Recommended Sizing for Hot Water Line
FIXTURE UNITS PER PLUMBING FIXTURE
For best results, refer to the
Uniform Plumbing Code. This is only a guide and does not take precedence over your local
building and plumbing codes.
Stand By Mode
1. Electricity On
2. Power Indicator Light On
3. persists Check OK
4. No Flame Sensed
To Turn On
(Average time from step 1 to 7 is approximately 3 seconds)
1. Hot Water Tap Opened
2. Water Flow Sensor On
3. Fan Motor On
Fan Motor > 1,000 RPM
4. Ignitor On
5. High Limit Fuse OK
6. Source Gas Solenoid Valve On (SVm)
Gas Solenoid Valve On (SV1)
Proportioning Valve On (VGO)
7. Flame Rod detects flame
8. Fire Lamp Lit
9. Ignitor Off
10. Thermistor Senses Temperature
11. Computer Monitors All Safety Functions
and monitors fan speed, flow sensor, thermistor,
proportioning valve to heat the water correctly.
To Turn Off
(Average time from step 1 to 5 less than 3 seconds.)
1. Hot Water Tap Closed
2. Water Flow Sensor Off
3. Source Gas Solenoid Valve Off (SVm)
Gas Solenoid Valve Off (SVI)
Gas Solenoid Valve Off (5V2)
Proportioning Valve Off (VGo)
4. Flame Rod detects no flame
5. Fire Lamp Off
6. Fan Motor Off
T-K1 Engineering Data
Recovery Rating (DOE) : 203 Gallons per Hour
Energy Factor Natural Gas : 0.70
Propane Gas : 0.72
Thermal Efficiency 80 %
Combustion Fan Assisted
Vent 4" round w/ vent cap for outdoor use
Electrical input 120VAC, 60 Hz