Sediment in lines -Bosch Tankless Water heater

Water leaking into elements. Bad PC board. Undersized breakers. Undersized main panel.
Bosch Powerstar is a computer that happens to heat water.
If your 5-year-old laptop computer was malfunctioning, you would not be surprised.
But for some reason (false marketing by manufacturers?), folks believe a tankless computer is going to last 20 years.
Moreover folks also believe tankless will provide endless hot water while saving money.
The whole idea of tankless saving money is a load of sales-BS that defies physics and common sense.
There are no service manuals... except bosch website has troubleshoot section in product manual.
Call a bosch-qualified service tech.
Go to Lowes and buy ordinary tank heater, and fix your heater today for only $250.
Tank-type electric water heater can be easily repaired and maintained by homeowner to last forever... that is a fact
http://waterheatertimer.org/How-to-maintain-water-heater.html

http://waterheatertimer.org/How-to-wire-Tankless-electric-water-heater.html

Gene

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

1) Add tempering tank to preheat incoming cold water.
http://waterheatertimer.org/Tempering-tank.html

2) Read product manual or call Bosch to make sure unit works with pre-heated incoming water. Some incoming water sensors will not trigger combustion is incoming water exceeds certain limit.

2a) Read product manual for required yearly/monthy maintenance.
Train wife to delime tankless yearly.

3) Install bigger gas meter.

4) Solve entire moneypit problem today for $325
http://waterheatertimer.org/How-to-install-gas-water-heater.html

5) Don't install tankless unless you have a lot of money and time for headaches.
Don't believe promotional literature. Tankless promotion is BS for average do-it-yourself folks who want to save a buck on water heating. Estimated yearly saving of $100 means Tankless do not save money long term. All costs are energy: Purchase price and installation negates several years saving up front. One repair will negate another 5-8 years energy savings. By then you need new unit.

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.pdf
http://waterheatertimer.org/pdf/Rheem-De-lime-tankless.pdf

Contact 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

http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html#flow
1) Tankless require minimum flow rate before burner will activate.
2) Sounds like the water pressure drops quickly when faucet turns on. This implies combination of problems including sediment build up inside lines, crossover at single-handled faucet, or sediment filter clogged or water softener clogged.
3) Low flow faucets can reduce needed flow rate.
4) Other problems can contribute: sensor failure, loose wires, PC board failure, high temperature setting, cold incoming water temperature during winter months.

Can tankless electric water heater be repaired? Sure.
Is it worth the expense if problem is going to happen again? I can't answer, but can offer resources.

New tank-type electric water heater costs $207 and new tank-type gas costs $320 at local box store.
You can install new tank-type electric yourself in a couple hours. DIY repair on tankless is not easy since parts are not at local box store, and what part do you need, and tankless parts can easily cost more than new tank-type water heater.

Open following link for Bosch troubleshooting resources.
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html

GENERALLY, Tankless require .4 gpm (gallons per minute) water flow to activate heating cycle, and then require .25 gmp flow to keep heating cycle going.
For example .4 gallon per minute means faucet can fill 1 gallon container in 2-1/2 minutes
Some tankless units require more water flow, for example .75 gpm

Tankless water heaters have flow sensor that tells computer chip when enough water is flowing to activate heating cycle.
If the sensor is clogged, or if water filter inside tankless unit become clogged with dirt or sediment from hard water, then the unit does not signal enough water flow and will not activate.
Home filtration system and water softener can also slow the flow of water.
Low water pressure and crossover problem on single-handled faucet and crossover on recirculation system check valve and high thermostat setting can also cause heat cycle to not activate.

Tankless cannot be exposed to water with more than 11 grains hardness or parts inside tankless will coat with sediment and not work. Within 2 years the unit will not work, with diminished efficiency from the beginning.
http://waterheatertimer.org/Battelle_Final_Report.pdf

If water is hard, and you cannot soften the water, or if water is dirty and cannot be cleaned, then the best recommendation is to use tank-type heater instead of tankless.

All costs are energy. For average home: Tankless electric is NOT cheaper to operate than tank-type electric. Tankless gas saves $1-8 per month. However, cost of unit and installation, cost of potential repairs and cost of parts, difficulty of DIY repairs, required yearly-monthly maintenance, etc outweigh expected savings.
http://www.pmengineer.com/Articles/Cover_Story/8cf9e86f7c298010VgnVCM100000f932a8c0____

Upvote the help.
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.

Before calling service technician, open following link for Bosch troubleshooting steps.
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html

If you are not getting error code, then problem could be somewhere in plumbing, as you suspect.
For example cross-over on single-handled faucet, or faulty check valve on re-circulation system, or sediment clog at elbow, or varied water-well pressure. Install in-line pressure tank.
http://waterheatertimer.org/pdf/Bosch_Overcoming_fluctuating_temps.pdf
http://waterheatertimer.org/pdf/No-Error-Code.pdf

Be sure to read manual for yearly maintenance protocol.
Tankless must be maintained, and cannot be exposed to hardness in water greater than 11 grains, and should be de-limed each year. Expect maintenance, service, and potential repairs and parts for tankless to far exceed expected $1-8 monthly savings. All costs are energy.

All gas tankless brands can be repaired by homeowner for $330.
http://waterheatertimer.org/How-to-install-gas-water-heater.html

Before calling service technician, open following link for Bosch troubleshooting resources:
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html

http://waterheatertimer.org/pdf/No-Error-Code.pdf

Problems can range from sediment in tank, to clog in plumbing elbow, to degraded joint where copper and galvanized pipe meet, to crossover in single-handle faucet, to leak in water line, to leak in TP valve, to bad check valve, to defective re-circulation pump system.

Tankless should never be installed with plastic pipe, PVC or CPVC etc.

Before calling service technician, open following link for Bosch tankless troubleshooting resources, including Bosch contact information, typical manuals, error codes, tech support, parts, fuel-saver calculator, service bulletins, water heater forum, fixya links, disclaimers, and links for finding service technician.
http://waterheatertimer.org/Troubleshoot-Bosch-Tankless-water-heater.html

Read manual cover to cover, make sure tankless receives yearly maintenance as outline in manual.

Add a comment with your experience so others with same-similar problem can benefit.

Also 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.

1) You posted under Bosch tankless water heater.
There should be a nameplate on front of unit or located where you can see it.
http://www.boschhotwater.com/HelpfulResources/TechnicalSupport/BoschAquaStarModels/2400ESTechSupport/Troubleshooting/tabid/1295/Default.aspx

Bosch problems at Fixya:
http://www.fixya.com/support/p949576-bosch_1600h_lp_liquid_propane_aquastar_a/solutions

Bosch has online tech support form:
http://forms.boschhotwater.com/Home/BoschTechSupportForm/tabid/614/Default.aspx

2) Replacing water valve probably loosened build-up inside pipe that lodged in water heater or inside elbow just beneath tankless unit.
If water flow is stopped or slowed, tankless will not operate.

3) Remove pipes and see if clog can be flushed.

4) Also U-tupe search "delime tankless water heater" and technique used for deliming will be good way to clear out tankless clog and sediment.
Your tankless should be delimed each year anyway.

5) Read your manual cover to cover, and see words 'troubleshoot' and 'maintenance' are used throughout manual. Get acquainted with your water heater and manual, because tankless are maintenance heavy, especially if conditions are not optimal and as unit ages.

6) All costs are energy. Install tank type water heater for ez do-it-yourself repairs and maintenance.
Tank type work under all types of adverse conditions and water pressures and water conditions, and even withstand sediment build-up for several years. Of course tank-type pipes can clog too.
http://waterheatertimer.org/How-to-install-gas-water-heater.html

Add a comment for more free help.
Also 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.

Some tankless heaters have filters built into the machine. You might want to consult your owner's manual regarding the filter.
The minimum flow rate is hard programmed into a tankless heater; it won't be changing over time. You might want to check the aerators of your fixtures for buildup of sediment and scale.
The temperature control of Bosch units is always going to be crumby because they are cheap products. The only thing you can do to improve temperature stability is to increase water flow (de-scale fixtures and possibly remote flow restrictors)