Bosch AquaStar 2400ES-NG - Page 9 - Answered Questions & Fixed issues

Copy following link:http://waterheatertimer.org/pdf/Bosch_A2_error_code_troubleshooting.pdf If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

Yes you need to delime tankless each year.http://waterheatertimer.org/pdf/Bosch_Descaling-heat-exchanger.pdfhttp://waterheatertimer.org/pdf/Rheem-De-lime-tankless.pdfContact Bosch for exact repair information. My records show following number for tankless gas: 800-642-3111 http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

is this an area w/a threaded fitting?if so ,you turn off waterheater,drain,disconnect existing fitting,clean and rewrap with new teflon tape ,and retighten down.i only say to drain,because i am not sure if it is hanging and would not want to fall on you.teflon tape and rewrenching down should fix,unless soldered.then call your plumber.also if under warr.from installer ,less than 1 yr.,call them and tell them to fix it for free.i have over 13yrs in sheetmetal install,both in hvy.industrial down to many other types of home install of furnaces,a/c units,retrofits in /new and existing homes,waterheaters,garbage disp,refrig.water lines,gas etc

If all the other faucets work, then the problem is the mixing valve in your shower. You will need a new shower fixture.

The problem is the gas valve assembly. Have your local utility service come out and check it, they do the check for free.

Before calling service technician, open following links for Bosch error codes, and contact information, and possible product manual for your model, etc:
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html
http://waterheatertimer.org/pdf/Bosch_EA_error_code_troubleshooting.pdf
http://waterheatertimer.org/pdf/Bosch-GWH2400ES-error-codes.pdf
http://waterheatertimer.org/pdf/Bosch_A4-E4_error_code_troubleshooting.pdf

Error code AE is not shown, but error EA means "burner flame not recognized by control unit when water is flowing"

There is also error A3 and A3 E3: jumper connection is not correct

Ok that sounds more life a faucet that is bad. In today world, the newer (20 years and less) they have pressure balance faucets. Have the faucet serviced. NOW lets look at an other area check out your home to see if you have a cross connection. A cross connetion is a place where hot and clod water meet. I know that everywhere but the toilet!

Yes thats true. But we buy all kinds of things that we attach to a fauects or tub spouts. Lets say you attached a hose to the sink in the garage to wash the dog with warm water. if you turned the water off at the handle of the hose and you left the water on at the faucet. BINGO

the hot and cold water mix and then up and down water temp while taking a shower.

So start looking first before spending any money. if ANYTHING is attached to any faucet take it OFF and then take a shower.

Be safe

Thanks

Tom ( how did we do ?) :)

There are service bulletins concerning water valve rebuild and water valve retrofit that may be useful:
http://www.boschhotwater.com/HelpfulResources/TechnicalSupport/BoschAquaStarModels/125BTechSupport/ServiceBulletins/tabid/384/Default.aspx

From retrofit service bulletin:Old brass valve is replaced with improved plastic water valve.
Two sets of screws hold water valve against gas valve.
Descale water valve with CLR if it will not remove easily.
Call 800-642-3111 for help

Fix most tankless water heater problems yourself, same day for about $350.
http://waterheatertimer.org/How-to-install-gas-water-heater.html

Take a moment and rate answer:
And take advantage of fixya expert assistance live.
For a price, expert works with you while you work on water heater or any do-it-yourself project.
Fixya is always less expensive than a service call.

http://www.bosch-climate.us/files/201101161946320.GWH425HN_English111104.pdf

7. Poor circuit connections at the ECO (overheat sensor) or the flue gas safety device
Ignition sparker will not operate if the electrical circuit is

interrupted. Check that the connections to the ECO and

Flue Gas Safety Device are secure and tighten if necessary.

If the 425 HN is Powervented, check spill switch reset

Is the most likely cause of the problem you describe.

http://www.tanklessking.com/Products/Tankless-Water-Heater-Flushing-System__RTG20124.aspx
http://www.tanklessking.com/Products/Tankless-Water-Heater-Service-Valve-wIntergral-Check-Module__TWH-UT-HC-RV.aspx

Generic help info:
http://waterheatertimer.org/pdf/Rheem-De-lime-tankless.pdf
http://waterheatertimer.org/pdf/Tankless-maintenance.pdf

Instructions for relighting pilot on Tankless water heater are in the product manual:
Model number is on label located on side of unit.
Open following link to help identify product and download possible manual:
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html

For tank-type water heater, the lighting instructions are usually printed on side of tank in addition to the product manual.

Find the model number and re-post question with as much information as possible for more assistance.

Open following links to identify product and download manual.

Piezo ignition
http://www.boschhotwater.com/Portals/7/TechManuals/125BO_English.pdf

Electronic ignition
http://www.boschhotwater.com/Portals/7/TechManuals/125FX_English_12_yr.pdf

http://www.boschhotwater.com/HelpfulResources/BrochuresManuals/tabid/354/Default.aspx

http://www.boschhotwater.com/BoschHotWatercomHome/GasProducts/AquaStar125Series/tabid/343/Default.aspx

http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html

Open following links for possible manual:
http://waterheatertimer.org/pdf/Bosch_10P-installation.pdf
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html

http://www.bosch.com.au/content/language1/downloads/bc2600_Owners_Guide.pdf
Above is a guide that may be of help to you. Below is a Bosch technical support site...
http://www.boschhotwater.com/HelpfulResources/TechnicalSupport/tabid/334/Default.aspx

Try unplugging the unit's power cord or shutting down the breaker or fuse at the power panel. This should "reboot" the computer chip on the control board and return the unit to normal operation. Losing power has an adverse effect on computer chips and memory sometimes, and a reboot will right the ship on most occasions

I have not seen this exact fault code? However the 7 series, usually indicates a problem with either the temperature, maybe a sensor, thermostat, or the Main Board? As with ALL gas appliances, I am bound to tell you to seek professional help.. so that's indeed what i advise, contact a professional and go from there?

Open following links for Bosch tankless resources, including some 1600 manuals, and contact information for Bosch:
http://waterheatertimer.org/pdf/Bosch-1600H-indoor.pdf
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html
http://www.boschhotwater.com/BoschHotWatercomHome/GasProducts/tabid/331/Default.aspx

Tankless burner parts and combustion chamber need yearly cleaning, and tankless should be delimed each year.
http://waterheatertimer.org/pdf/Bosch_Overcoming_fluctuating_temps.pdf
http://waterheatertimer.org/pdf/Delime-tankless-water-heater.pdf

I can help steer you to resources, including Bosch contact numbers and possibly your manual and other helpful information:
http://waterheatertimer.org/Troubleshoot-Rheem-Tankless-water-heater.html

take the cover off the 10 h unit light up the burner by turning on the tap turn the water flow tap on the front of unit (white knob) clock wise slowly feel hot water pipe coming out off unit when temp increases put cover back on check temp at sink if too hot turn knob anti clock wise

First suspect is air in gas line or dirty combustion parts.
Typical gas water heaters today suggest cleaning burner parts yearly, including bleeding air out of gas line.
Use a burner brush to clean tubes:
http://www.rvparts.com/product-85-91872

Other suspect could be faulty wiring or bad gas valve.

Symptoms sound like crossover might be part of problem:
Crossover is when cold water enters hot water line due to faulty plumbing part like check valve, mixing valve, or bad faucet cartridge.
http://waterheatertimer.org/Crossover.html

Natural Gas: Pilot burner or orfice may need to be cleaned. Pg 11 manual.
http://www.boschhotwater.com/Portals/7/TechManuals/125BL_English.pdf
Most tank and tankless gas water heaters today suggest annual cleaning and maintenance of burner.

Open following links for Bosch troubleshooting resources:
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html
http://www.boschhotwater.com/HelpfulResources/TechnicalSupport/BoschAquaStarModels/125BLTechSupport/Troubleshoot/tabid/474/Default.aspx