Search waterheatertimer.org
/
all results
|
How water heater thermostats worksGas and Electric |
Gas thermostat located inside copper tube on back of gas control valveNatural gas or propane gas enters the gas control valve thermostat through a yellow flexible or black pipe gas line.If thermocouple or thermopile is correctly positioned in the pilot flame, then a small voltage is sent to gas valve indicating that it is safe for gas to enter the valve. With the mechanical gas control valve thermostats, the pilot flame heats the end of a thermocouple. A thermocouple is 2 dissimilar metals joined together that produce small current when heated. The small electrical current travels from the thermocouple though copper line to the bottom of the control valve, where it connects to an electromagnet. When the electromagnet is energized, it holds open the safety valve as long as the pilot flame is heating the thermocouple. When the magnet closes, it makes audible sound that can be detected when troubleshooting. If the pilot flame is extinguished, it can take up to 180 seconds for the thermocouple to cool sufficiently for the electromagnet to de-energize and close the safety valve. The safety valve controls whether gas flows into gas control valve. If safety valve is open, then gas valve operates normally, and releases gas continually to the pilot light through the pilot gas regulator valve, and releases gas to burner through the main regulator valve when thermostat probe detects water temperature is below set point as selected on dial located on front of gas valve. With the electronic gas control valve, the pilot flame heats a thermopile. The thermopile works on same principle as thermocouple, except is larger and creates more current than thermocouple, enough current to power a circuit board inside the gas control valve. Unlike thermocouple, the current from thermopile travels to gas control valve through two wires that connect to front of gas control. The circuit board controls a series of self-check routines, error compilations, etc and uses electromagnets to control flow of gas to pilot and burner. See basic gas water heater parts If no current is produced by thermocouple or thermopile, then gas to the valve is shut off until pilot is re-lit or defective thermocouple or thermopile replaced. The temperature-reading thermostat on a gas valve is located inside a copper tube that protrudes into tank and reads water temperature. When water temperature drops below selected thermostat setting, then the gas valve releases gas through the manifold tube and into the burner located in combustion chamber. How to adjust temperature Gas flows out of the burner where pilot light ignites gas. If burner is dirty, sooted or obstructed, the gas may not light immediately, resulting in unburned gas building up until it reaches the pilot flame causing explosion hazard. Sooted and dirty burner and yellow flame indicate this problem. After cleaning the burner and the combustion chamber, the gas should burn blue with bits of red and yellow. Clean burner The burner heats bottom of water tank, and water is heated. Hot water rises to the top of tank, and gas continues to burn until bottom of tank is heated to the thermostat setting, causing gas control to shut off gas to burner. If the temperature inside combustion chamber exceeds maximum limits, then the gas valve thermostat could be malfunctioning. The overheating will trip the TCO thermal reset located on front of combustion chamber. This will shut off the gas valve until TCO is reset. On modern gas water heaters, if incoming air supply is constricted then the flow of hot combustion gas up vent is slowed and trapped inside combustion chamber. Result is overheating in combustion chamber. Different water heater companies have different air intake systems. Depending on overheating event and specific model of water heater, the TCO needs to be reset. The repair could be simple cleaning of air intake screen, and resetting TCO thermal reset and assessment of incoming air supply and venting. Water heaters operate at 61-62% efficiency. The excess heat and poisonous by-product from combustion process is vented up the vent and out of each home into atmosphere where you breathe it. Calculate efficiency |
||
Gas control valve thermostat |
ECO energy cut off will
trip if water inside tank exceeds 170 F. ECO is usually single-use and gas control must be replaced How to test ECO White-Rodgers and Robert Shaw Intellivent gas control ECO can be reset |
|
If water temperatures fluctuate at
tap, then Gas control can be bad -or- there is plumbing problem Check temperature at tank drain valve and TP valve and compare with temperature at tap Adjust temperature at tank Crossover: single handle faucet has bad cartridge and other causes Stacking: several short water draws cause very hot water How to replace gas control How to replace gas control |
Electric water heater thermostatsHow to troubleshoot electric water heaterHow to wire thermostats |
|
Buy residential upper and lower
thermostats Thermostats are interchangeable/ each works with your water heater 89T is discontinued/ replace with Apcom or Therm-o-disc Buy 90-150° F for residential tank: Rheem UV11698 Rheem SP11698 Camco 08163 Aprom / 110-160° Water heater thermostats at Amazon Camco thermostats at Amazon More thermostats |
|
Buy
commercial upper and lower
thermostats Buy commercial thermostat 120-180 degree F Rheem SP8293 / 170° Camco 08304 / 180° Rheem SP8295 / 170° Camco 08314 / 180° Resource Read more about 3-phase water heater Residential tank thermostat is rated 90-160° F Residential tank is NOT rated for pressure and temperature of 170-180° water. Only use 180 F thermostat on commercial water heater that is rated for high temperature Only use 180° F thermostat on commercial water heater that is rated for high temperature Marathon water heater is rated 170° F Thermostat for 3-phase non-balanced water heaters up to 480 Volt Resource How to change 3-phase water heater to single phase |
See
Larger
Some thermostats, the
L2 and T1 screws are empty slot or rivet since wires do not connect to
either L2 or T1.
Brands of thermostat vary slightly, screws are located differently, some numbers are slightly different, but basic concept is same from brand to brand. Water heater manuals available on-line. Label on side of tank shows watts and volts of appliance. Each thermostat comes with instruction sheet. When replacing thermostat, take digital photo of water heater and old thermostat to hardware store or plumbing store for quick identification. Thermostat must sit flat against tank wall so temperature reading is accurate and water heater is protected from overheating |
Residential
water heaters can be wired 4 basic ways. Non-simultaneous which is found in most residential water heaters, simultaneous, redundant, off-peak. The key is knowing how a thermostat works. Diagram on left illustrates basic thermostat function found on 240 Volt water heaters that have 2 elements. Check label on side of tank for voltage info. See diagram below. Power from breaker box connects to L1 and L3 screws > some thermostats, the screws are marked simply 1 and 3. Top half of thermostat is the ECO or energy cut off > The ECO is heat sensitive, so if temperature reaches dangerously high 150-180°F, then ECO trips and water heater no longer has power. This prevents water heater explosion. Viewing the diagram, power from L1 and L3 pass through ECO red reset and go to L2 and L4 screws. After power passes through ECO, it is available for heating water. To control heating, power arrives at the thermostat which begins at T1 screw. Inside the thermostat is bi-metal switch. Two different metals are fused together. Each metal expands differently when heat is applied. Since the two metals are joined, the metal that expands most causes the bi-metal switch to bend. The bending action opens and closes the switch. In the diagram, the bi-metal switch is connected to T1. When temperature inside tank is cool, the bi-metal switch rests against T2 so power travels from T1 to T2, and then on to the upper heating element. When temperature inside tank is hot, the bi-metal switch disengages from T2 and clicks over to T4. When this happens, T1 sends power to T4, so the upper heating element is turned off and power travels to lower element and thermostat through the T4 screw. In a 240 Volt water heater, elements must receive power from 2 hot leads to complete 240Volt circuit. Both elements have 1 wire connected to L4 screw on upper thermostat. So both elements test hot for 120 volts at all times. When the thermostat switches and sends power to element, that action completes the 240Volt circuit, and element turns ON. See basic water heater circuit |
See larger |
Screw
numbers on upper thermostats Upper thermostat is made of two parts >> the top part is the ECO, the bottom part is the thermostat |
Bradford White tank |
Non-simultaneous
water heater wiring This wiring is found in most residential water heaters. Check label on side of tank. Both elements are never 'on' at same time unless tank is wired for other purpose (see owners manual). This is called 'non-simultaneous operation' since both elements are not 'on' at same time. Either upper element is 'on' or lower element is 'on,' or both are off. Upper thermostat is
main controller <> it turns on upper
element until temperature is reached, and then sends power to lower
thermostat.
Thermostat
reads temperature through wall of tankCheck thermostat sits flat against tank to prevent overheating |
Dual element upper
thermostat
Screw numbers include L1, L3, L4, T2, and T4 |
How to wire 240V dual element water heater thermostat | |||||
Larger image NON-simultaneous: Household electric water heaters are wired for NON-simultaneous operation. Both elements are not ON at same time. Upper element is ON, or Lower element is ON, or both elements are OFF. |
|||||
Off-peak
water heater wiring See page on off-peak wiring Purpose of off-peak ... save energy during peak electric prices. > Upper thermostat operates normally to keep top 2/3 tank hot. > Less hot water is available. > Lower thermostat heats bottom 1/3 of tank only when ordered by off-peak meter or timer > Off-peak ends, and tank resumes non-simultaneous operation |
|||||
Larger image |
|||||
OFF-Peak
Non-simultaneous operation. Lower element turned OFF during off-peak. Upper element keeps top of tank hot Less hot water is available. When off-peak ends, normal NON-simultaneous operation resumes. |
|||||
|
|
|||||
How to install electric meter on electric water heater |
Buy Electronic parts Industrial supplies Tools and home improvement Home and garden Hayward pool Pentair pool Southwire electric |
|
Buy
Tools DEWALT Black and Decker Stanley SKIL Makita Porter-Cable Bosch Irwin Hand tools Klein hand tools Fluke electrical testing Dremel hobby tools Campbell Hausfeld air powered Tekton automotive Powerbuilt automotive Saws and saw blades |
|
Resource: Compare box timers DPDT timers Intermatic Control water heater w/ Z-wave |
|
Resource: Intermatic control centers: and parts Digital control centers and parts Tork control centers and parts Subpanels All control centers and parts Enclosures |
|
Resource: Programmable timers Countdown timers Off delay timers On delay timers Timer modules Din rail Twin & one-shot Woods Intermatic Tork |
|
Recirculation systems |
Buy
from my affiliate links every time/ thanks: Amazon As an Amazon Associate I earn from qualifying purchases Enter Amazon from any link on my site, fill cart with any item ... purchases pay small commission E-mail: geno03245w@gmail.com My response might end up in spam folder, check email folders Waterheatertimer on Twitter Message thru facebook |