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Troubleshoot  Rheem  tankless water heater

Rheem tankless
Search this page: Crtl+F
It's not working?
And there are no service manuals. How does anybody know how to fix it?

Tankless troubleshooting resources for homeowner
Search this page: Crtl+F
Remember, Tankless is a computer that happens to heat water.
It's not ordinary water heater.
Regular do-it-yourself folks are probably NOT qualified to install, maintain, diagnose and repair tankless, and the resources on this page might not apply to your model... since models vary widely as refinements are made in technologies such as corporate promotion, and consumer targeting.
Don't install the dam thing and you can avoid most problems.
Buy: Tankless water heaters at Amazon
Tent City USA tankless water heater/ off grid
Rheem Tankless logo
Larger logo

Gas odor

If you smell gas, leave building immediately and call gas company from outside

Natural gas is lighter than air and odor will rise to ceiling.
Propane gas is heavier than air and will settle to floor. Do not install propane tankless in basement.


Crossover models and general parts sheet
Cross reference/ pdf

Will not turn ON

Nothing happens when water is flowing through tankless unit:
Unit will not power ON/ pdf
Check the electric 2008/pdf
How to light tankless 2009
How to light tankless 2012


There is a 3-amp power line fuse and/or 5-amp board fuse located on PC board (circuit board).
Fuse trips when heat on the line exceeds rating on fuse. This stops damage to vulnerable electronic parts.
If fuse is blowing, maybe there is a short circuit or overheated part on the PC board. Replace board. Pay for service.
See 2012 image of fuse
See 2008 image    Another fuse image
Check the electric troubleshoot from 2008/pdf

Tankless gas water heater must be plugged into 120Volt outlet to supply power to electronics and sensors
Outlet must have correct polarity and be grounded. Outlet must provide at least 80% rated voltage.
Test outlet with circuit analyzer and multimeter
Burned out fuse

More electric wiring

Electricity must be ON / Outlet must have correct polarity

Applies to gas Tankless
No electric power = no hot water
Tankless gas units require 120Volt outlet. Outlet must provide at least 80% rated voltage. Read product manual.
Do not connect to 240Volt or 208V or 277V etc. Voltages other than 120 volt AC can damage circuitry on tankless.
Do not connect tankless directly to a PV solar panel that supplies DC voltage, or any source of DC power. Although a 48 VDC tankless might be interesting concept for rinsing off the livestock.
Recommend dedicated circuit (one breaker supplies power to outlet, and no other outlets). See illustration of 120V circuit
Do not use extension cord.  Generally, extension cords do not deliver reliable power without occasional voltage drop.
Outlet must have correct polarity, and be grounded.
Use circuit-analyzer to check outlet.
Circuit analyzers at Amazon
Electric tankless
Tankless electric require 208-240Volt
Read manual
Also read following illustrated guide for wiring
How to wire tankless electric

Action for Error code 

What to do when Rheem tankless error code is displayed: What to do/ pdf
Maybe pushing both up-and-down arrows on remote control will reset error.
1) Turn off all hot water faucets  (2) Power off: At remote control, turn off water heater by pressing Power on/off button (3) Power on: Wait 5 minutes and press Power on/off to turn on water heater (4) Turn on hot water faucet and check for error display (5) repeat if necessary (6) If problem continues, read error information below for do-it-yourself resources, and/or call 800-432-8373 for recommended service and to hear Rheem tell you to call installer first, and/or service technician next.
Rheem does not post service manuals.
-NO ERROR code? Read no error code pdf
-Tankless water heaters require regular maintenance to avoid typical problems: Maintain your water heater/ pdf   Maintain water heater 2012/ pdf

Error codes

Error codes 2012
Error codes/ 2008 service manual
Error codes 1 thru 99
Error codes/ Rheem tankless service manual
Error codes from Rheem
Paloma-Tankless-Error-Codes/ pdf
Rheem fault codes/ pdf
Rheem error codes/ pdf
Fault codes/ pdf

Tankless service bulletins

Multiple error codes could mean PC board failure.
Call Rheem and they will send new PCB.
Don't buy a tankless.

Error code C7 76 pdf  read pdf/ Open links to left
Error C7 75 PC board replacement, call Rheem
Error IL : delime yearly tankless pdf
Error code C7 pdf: read pdf, Open links to left
Error 76 at fixya
Error 76 from service manual
Error code C8 76:  PC board: open links to left, call Rheem
Error 82: wrong gas / bad PC board/  set for high altitude using dip switches/ pdf
Error code A1 21 A0 21: Open links to left
Error code C2 11: Open links to left
, clean combustion parts, call Rheem Error code 11 troubleshoot
Error WT
Error code 1L is 'lime build-up" Delime tankless yearly
Error code C4 13 pdf:
Error code 13 .pdf
Error code 13 troubleshoot/ pdf  thermocouple, oxygen sensor/ vent problem. Read pdf/ Contact Rheem
Error code C7 13: Contact Rheem
Error 10
Error 12
Multiple error codes: Clean and maintain unit. PC board is bad. Contact Rheem or service tech
Rheem error code P1/pdf: increase water flow/  replace plumbing
check valve/ clean water filter each month/  Read pdf/  Also read
Error code P1  not enough water flow
Tankless remote control
Error 76
Cause: Bad remote control -or- Bad wire between tankless and remote control -or- Bad PC board
Tankless will operate without remote control
Read pdf:
Error code C7 76 pdf
How to install Rheem remote control/ pdf
How to adjust temperature using remote control/ pdf

Main control at Amazon
2nd control for bathroom
RTG20009 18 ga wire wire for remote control
Delime tankless
Larger image
Error IL
Build up of scale inside heat exchanger. You must use water softener with tankless water heater or parts will fail within 2 years
Tankless heat exchanger is prone to scale build-up, and must be delimed each year. Error code IL means delime.
Deliming will not restore full efficiency. Read research
Error IL Resource:
How to delime tankless water heater
Maintain water heater 2012/ pdf
Rheem-De-lime-tankless/ pdf

Buy flushing kit
Tankless flushing kits

tankless service valve
Buy service valves
Tankless service valves

Buy submersible pump:
Submersible pump
Filter washers at Amazon
Washing machine hoses at Amazon
Rheem tankless TP valve Rheem tankless pressure relief valve
Attach to service valve installed on hot side. Must be on Hot side so valve can monitor water temperature as it leaves tankless
Purpose of TP valve is to release water when temperature or pressure exceed dangerous levels. TP valve is safety feature.
Attach 3/4" plastic or metal pipe from TP going downward to within 6" of floor at nearby floor drain. Pipe cannot be threaded at termination or capped-off or obstructed. When installing TP, apply 6 wraps teflon tape on threads.
TP releasing large amounts water periodically can mean bad thermostat or problem with tankless unit.
TP can release water when TP valve is defective, and when debris is caught under lever.
Use fingers, raise TP lever and then gently lower back into place. If TP continues leaking or drizzling, then replace TP valve.
Rheem tankless TP temperature-pressure relief valve
TP valve code
Troubleshoot TP valve
Tankless TP valve
Larger image

Got a bug?

More error codes/ Possible PC board failure

Error codes do not apply to each model
Multiple error codes could mean PC board failure.
Error 76
Error 11
Error 11 #2

Error 00
Error 11
Error 14
Error 15
Error 16
Error 21
Error 24
Error 29
Error 31
Error 32
Error 33
Error 35
Error 38

Error 51
Error 52
Error 61
Error 71
Error 76
Error 79
Error 80-81
Error 82
Error 90
Error 99

Take one down
pass it around
98 error codes left to go
Parts are free under warranty. Call Rheem with model and serial number.
You get new PC Board.
Read page 11 2008 service manual when installing new chip

But wait, that's same as replacing motherboard on your computer.
Do you really expect computer to be trouble-free afterward?
For 20 years.

Read warranty before you buy. Look at parts sheet. Be real.
Save money, keep it simple.

My electric water heater has 12 parts, each available at local store.

Clear error code maybe

Clear fault history
Clear fault history/ page 11 service manual 2008
Service manual 2008
Clear IL error code

No error code?

No error code pdf
No error code 2/ pdf
Unit will not power ON/ pdf
Crossover and Low water pressure
Sample Vent-kit installation/ pdf
Roof venting/ pdf
Ventilating tight house/ pdf
Read spec sheet
Maximum 35' length for vent  Venting specs   Chart
Rheem generally require .4 GPM minimum activation rate of flow and .25 GPM minimum rate of flow to keep heating
Keep water filter clean. Must use water softener.
Bad faucet cartridge, or recirculation check valve can cause no heating: Crossover
Very cold incoming water can cause tankless not to keep up with thermostat set point.  Install tempering tank  Reduce temperature setting
Default temperature setting for new tankless 100 degrees F. Without remote: default 120 degrees F
Minimum temperature setting 85 degrees F
Tankless must be connected to 120V outlet with correct polarity. Electrical: standby 3-5 watt, operating 100 watt
No error code

Do the maintenance

Stick man pointing
Woo Hoo

Prevent common error codes

Clean water filter monthly, delime tankless yearly!! Big family fun!!
Tankless operation overview/ pdf
Maintain your water heater/ pdf
Maintain water heater 2012/ pdf
Removal and cleaning Rheem Tankless burner
Paloma use and care
Buy flushing system $199 or Buy whole new tank-type water heater $207
Rheem tankless
I like projects

Another image
Clean water filter monthly
Error P1
Warranty does not cover failure due to water problems
Symptom can include low water flow
Turn off tankless at remote control, Turn off water, release pressure at faucet, remove and clean filter, or replace filter.
Check for other filters on household water line.
Also check for crossflow and crossover:
Read typical maintenance pdf
Maintain water heater 2012/ pdf

How to drain tankless

stick men heads

"Your're trying to take a shower??????
Well, that's why it doesn't work !"

Rheem offers on-line CHAT and PHONE Get out your wallet

Well, you bought the thing, moneypit.
Rheem 800-432-8373
Paloma warranty claim: maybe 805-278-5499
Rheem will tell you to call installer or call qualified service technician.
Ask how 'qualified' service techs fix Rheem tankless water heater when there are no service manuals.
Buy another one, lol: Tankless water heaters at Amazon
Rheem phone support
Remember, the purpose of the corporation is to remove all employees except those willing to mislead you in exchange for less pay.
repair tankless water heater
wear safety glasses

Tankless are computers that breathe air

Incoming air supply must be clean or parts get clogged.
Avoid dust, lint, grease, process chemicals.
Chemicals will corrode combustion parts and cause early demise of water heater.

If your 5-year old laptop computer stops working... are you surprised??????????

BUT Rheem promoters say ... tankless computer lasts 20 years.
Do you believe that hoo-ha coming out of corporations?

How tankless water heater works

Tankless Warranty:

1 year labor, 6 year parts

Same as ordinary tank-type heater

Rheem tankless warranty 2013
Paloma tankless warranty
Rheem tankless certificate of warranty 2008
Rheem tankless warranty 2006
Paloma limited warranty / Limited warranty? No labor?

Wait a minute.
Why doesn't warranty match the 20-year promotion?
Oh that's right, Rheem is one of those people with last name Corporation, so they allowed to lie up folks to get money.
They got laws to protect salesmen and promoters when they blow lies.
Of course that would be fraud if you did it to them. And they got laws for that too.

Don't forget, you have no hot water while waiting for warranty claim.
Install tank-type heater for $385 from Lowes and get your money back.
Tankless promotion
Does your old Apple 2E still work?


Vertical and horizontal kits

& Condensate drain

Rheem tankless venting kit Tankless horizontal vent kit Tankless condensate drain venting tankless
Buy vertical venting kit:
Rheem tankless venting kit
Rheem tankless venting kit
Rheem tankless venting kit
Rheem tankless venting kit
Rheem tankless venting kit
Buy horizontal vent kit
Vertical or horizontal
Tankless horizontal vent kit
Rheem Tankless vent pipe
Tankless vent pipe
High temperature Tankless condensate drain

Tankless venting/ pdf
Bradford White venting .pdf


Black soot indicate improper vent on any type gas appliance.
All gas appliances must be properly vented or the combustion by-product can kill.
Evidence of bad vent can be headache that goes away when you leave house. Also lethargic, unresponsive people. Immediately remove people from home and lay on side. Do not lay on back. Call emergency. Open windows. Call plumber to check vent.

Venting a tankless

Tankless venting
Read your manual for specifics
Use category III or schedule 40 pvc as shown in product manual.
Ordinary 3-4" galvanized vent pipe will NOT work.
Aluminum vent that is typically used for clothes dryer will NOT work, unless you're under water financially and intending to set the illiquid asset afire.
Venting is important for the higher heat from tankless, since larger gas line supports larger burner and more-high-temperature toxic by-product must be vented outdoors where it can assist nature.
Must have condensate drain so acidic combustion by-product does not drip into heat exchanger and burn hole through expensive metal alloy heat exchanger,,, of course you don't know if condensate drain works until heat exchanger gets a hole a few years from now. Oh well, it's just money.
Now remember, acidic water is good for your floor drain and sewer lines if condensate drain happens to work right.
Bradford White venting .pdf

Larger image

Condensate drain

Burning hydrocarbon produces combustion by-product.
By-product includes CO2 CO NO SO and acidic water vapor.
These respiratory poisons are puffing out of every vent stack across globe.
But wait, promoters say natural gas is 'clean burning' ... and you believe that ... well, er uh, except you can't breathe the poison.... which is why there is a vent.
Tankless burn more fuel per gallon of heated water than tank-type heater. This is necessary to raise temperature as water quickly passes in a pipe.
The larger amount of combustion by-product means tankless must have larger vent pipe. The pipe must also be made of material resistant to acidic water vapor.
The acidic water vapor will frequently condense inside vent pipe, and drip back into tankless unit.
To prevent acidic water from destroying the heat exchanger, a condensate drain is required.
The condensate drain redirects acidic water away from the tankless and down into a nearby sewer drain, where the acid will destroy vulnerable types of pipe, before emptying into your drinking water and oceans that contain your food.
As a result, the 'clean burning poisons' end up in your body one way or the other.
I was wondering if anybody has tried installing a flat plastic pan to catch the condensate so it evaporates into air?
High temperature Tankless condensate drain
Rheem condensate drain /pdf
9 ways to save with water heater

Gas line

Do not use flexible gas line. Must use minimum 3/4" solid black pipe gas line. Look at specs in product manual.
Flexible gas line works with ordinary tank-type water heater.
But tankless will shut down if gas flow is restricted by flex line.
Error code 11 or C11 can be associated with undersized gas line, or using flex line.
Maybe error 12 can be related to this issue... just make a guess... or replace flexible line with 3/4" black pipe.
Do not use copper pipe unless local codes allow, and then use only pipe that is non-reactive with local gas supply.
Always connect tankless with at least 3/4" black pipe or equivalent. Also must run 1" gas line to within 10' of tankless.
Why? Because tankless consume more gas to heat one gallon of water as water rushes past in pipe.
That is why it is silly to believe endless hot water will save money vrs tank-type heater that uses less gas per gallon hot water.
Use yellow teflon tape, or approved sealant. Do not let excess teflon tape or sealant enter pipe. Keep pipe connections clean
Install sediment trap in gas line to keep water and other debris from reaching gas valve inside tankless.
Sediment trap is usually a 3" long piece of pipe pointed downwards with a cap on the end.
Check gas pressure. Make sure gas meter is large enough to support all the gas appliances connected to meter.
Not enough gas will starve appliances, and cause shut down of oven, stove, furnace and tankless computer.
Tankless gas pipe

Product Manuals/ Gas

Page 19 of manual says to clean water filter each month
Tankless condensing 2012
Rheem tankless Use and care 2009
Bradford White venting .pdf
AO Smith specs say maximum vent length for tankless 35 foot
Paloma use and care

Condensing tankless documentation/ on-line
Waiwela-Rheem manuals

Rheem tankless manual 

Read the manual.

Protect your warranty rights,eliminate common error codes by following advisories, maintenance, and installation

Product Manual/ Electric

Rheem-Tankless Electric-manual.pdf
How to wire tankless electric water heater


Rheem Tankless parts 2012
Rheem tankless parts
Tankless condensing parts
Part and accessories/ pdf
Burner assembly $185 plus installation
Example component replacement/ pdf
Image of parts list
Pdf of Rheem parts
Parts guide/ pdf
Order parts no returns

Get your China
Bosch transformer
Transformer only $223

Dang buddy,
You can buy whole new tank-type gas water heater for $385... well that was before 2015 heh heh
Buy whole new tank-type electric for $250
And save money to buy toxic Chinese dog food
chinese dog food

No Service Manuals?

No rheem service manuals

Rheem says there are NO service manuals 

BUT... wait ... How do service technicians know how to fix your tankless? By guessing?
How do qualified service technicians exchange information with each other and with customers if only certain people have repair information? How do young people get enthusiastic about a field if full information is not available?
Call Rheem before you buy and ask why they refuse to provide clear repair information to consumers.: 800-432-8373
How to de-lime tankless/ pdf
Read typical maintenance pdf
Maintain water heater 2012/ pdf
Tankless service bulletins
But no service manuals.

More guessing for consumer:. The Rheem product manual for tankless electric might no show how to wire the product.
How to wire tankless electric

Whoops, Liam sent 2008 Rheem Tankless service manual !!

Rheem Ruud tankless service manual 2008
Rheem tankless service manual/ possible 2011
He said he contacted Waiwela
General guideline: Probably won't apply to your tankless unit

Call Rheem 800-432-8373

Hey Rheem

Bosch tankless company posts service bulletins. But Rheem doesn't.

Bosch posted a bulletin how to remove and clean the burner.
Why isn't the American company as good as the German company?
How to remove and clean tankless water heater burner
How to replace tankless gas valve

This is probably how Rheem tankless technicians learn how to work on Rheem products.
More Bosch service bulletins
Bosch support center

OK.... Mat just sent me a Rheem service bulletin. Thanks Mat.
Removal and cleaning Rheem Tankless burner

Hey Rheem

Other companies post service manuals

Other companies post service manuals:
Bosch tankless service bulletins
AO Smith/ American tankless troubleshoot guides
AO Smith tankless service handbook
AO Smith general troubleshoot guide/ pdf
Example American tankless service manual
Rinnai tanless troubleshoot manual

Typical Rheem SERVICE MANUAL & part replacement/ pdf
Typical SERVICE MANUAL & part replacement/ pdf
Removing and cleaning tankless burner
Remove and clean burner 2
Repair tankless water heater
I can fix it this weekend
Fix tankless yourself ! 
Same day, for $385 before 2015
Install tank-type gas water heater from local box store.
How to install tank-type gas water heater

Or test parts, then order some parts online and see if it works.
Go without hot water until service technician can figure out problem.
Some problems cannot be solved.
Following manual applies to older tankless.
Rheem Ruud tankless service manual 2008

Buy another one anyway: Tankless water heaters at Amazon
Repair tankless water heater
I can fix it TODAY ??

Replace one part.
The whole thing.

How to repair tankless

Site: order parts
Tankless operation overview/ pdf
Rheem Tankless parts 2012
Tankless parts 2011

How to repair tankless water heater:
1) Ohm out a few parts using Bosch service manual
2) Call Rheem twice.
3) Order parts with overnight delivery. No refunds.
4) Parts arrive. Call Rheem.
5) Call Rheem twice next day
6) Install part without a service manual.
7) Still doesn't work.
8) Sell part on e-bay with overnight delivery.
9) DIY instruction: Install tank-type gas water heater for $385
10) Recycle metal as white goods for $6 per 100Lb

Ohm out a few parts.
Buy cheap multi meter for $10
Whoops dropped a washer.
Multimeters at Amazon

Checklist to see if you are right for tankless

Tankless repairs
Calipers at Amazon
Test, measurement and inspection supplies for professionals

All costs are energy

Typical family of 4 saves $1-$8 per month using tankless.
Factor in maintenance, possibility of expensive repair, no service manuals, no local service techs, cost of parts, cost of replacement, limited warranty, no warranty if you install yourself .... and that $100 per year savings looks like thin ice.
Better think it over Hoover.
Checklist to see if household suited for tankless/pdf
Class action lawsuit against Rheem tankless?

Don't get Rheemed: Avoid WT (wallet thickness) error/ pdf
If wallet is more than 2" thick, then you are approved for tankless.

Buy one lol: Tankless water heaters at Amazon

Abe says: do the math
I suppose if President Lincoln was alive today, he would be considered anti-business.
... Since plantations are business.
Tankless will clog with sediment

Must use water softener
Tankless cannot be exposed to more than 11 grains hardness in water
Efficiency will decline within few months.
Parts like pressure sensor will fail within 2 years
De-liming will not prevent failure
Warranty does not cover failure due to water problems
Bradford White study
Water softener research pdf
Sediment in tank-type heaters
Error code 1L is 'lime build-up" Delime tankless yearly
Clear error IL

When desired temperature setting is higher, less water can be heated.

Larger, more detailed image
High temperature limit
Paradox: Why do liberals want to conserve resources? That seems conservative.
You like the claim of 'endless hot water?' And the claim that tankless save money? Sound too good to be true?
Remember papa said: if it sounds too good to be true, look around for the fool.

Well? How come tankless need a bigger gas line and bigger vent pipe than ordinary tank heater?
It's because tankless consume more gas to heat 1 gallon of water than storage tank heater.
That's because it takes more fuel to quickly raise water temperature as water rushes past in a pipe.
Especially in winter when incoming water is colder.
Add a tempering tank
As a result: There is a temperature limit to tankless based on amount of water passing through burner, and water temperature.
Of course tank-type heaters have a limit too, based on strength of tank and pipes, but the limit is higher than tankless for ordinary residential models.

When you turn up temperature on tankless, it cannot keep heating same volume of water. Water flow must decrease or tankless will shut down. Remember the tankless is already consuming as much gas as possible. What a gulper.
So while tank-type heater can be set to 150 degrees, even if that temperature is unwise, the high temperature limit for tankless is closer to 120 degrees, which is why Rheem tankless cannot be set higher than 120 degrees using the remote control.
Each tankless unit is different so check specifications. Raising temperature on tankless can cause error codes.
Error code P1

How to set Rheem tankless temperature 2012/ pdf

It's too confusing
Temperature to kill bacteria

140F needed to kill bacteria on wash day

Tankless default is 120F with remote control, 100F without remote

Tankless cannot deliver 140 temperatures
Read about 140 temperatures on tank-type heater
set dip switches to adjust temperature
Charles emailed the following: FYI...To increase temperature from 120 to 140 on Rheem Tankless water heater most  documentation says to turn on DIP switch 4, then press SW1 on the left side for 1 sec., then turn off DIP switch 4.
It should be corrected to say press SW2  on the right side for more than 1
sec.  At least that's true for the RTG-74 units.  
Even original Manual was wrong.

Set temperature higher than 120 degrees F (requires service call)

Think about a really hot shower.
Or adding really hot water to the bath while sitting in the tub.
That's 130-135 degrees. Wow. Burn the right evil out of ya.

Rheem tankless default factory temperature is set at 100 degrees, without remote control.
Maximum temperature for Rheem tankless is tepid 120 degrees, using the remote.
Scald chart
By the time the bathtub is full, the overall water temperature inside tub is less than 100-120 degrees.
And temperature is even less if tankless is out of whack, or heat exchanger is coated with scale. ... which is why you have to delime tankless yearly.
Above 100-120 degrees and tankless might not keep up with required water flow, and shut down completely.
To set temperature above 120 degrees requires a service call to change dip switches, adjust water flow and flow sensors

How to set Rheem tankless temperature 2012/ pdf
How to change temperature on Rheem tankless using dip switches
How to change temperature on Paloma tankless using dip switches
Change max temperature setting 2008 service manual/ page 14-15
Add a tempering tank
Tankless dynamite
Wait for rain
Avoid forest fire
High altitude over 3280 feet above sea level
High altitude: \
Less oxygen to support combustion.
Equipment runs hotter.
Water heater must be rated for altitude, or dip switch adjustments made
High altitude dip switch setting
Adjust for altitude 2008 service manual pg 13-14
Altitude program chip part numbers/ pdf

Green shows when 120Volt Power is connected


RTG20009 18 ga wire wire for remote control
Tankless will work with or without UMC 117 control
Trace remote wire where it connects to unit, and remove wire connection.
Default temperature without remote control is 120 degrees F.

Tankless must remain plugged into 120Volt electrical outlet
Tankless require 120Volt outlet with correct polarity and grounding.
Tankless must be grounded.
Check outlet with basic circuit analyzer
Unit will not power ON/ pdf

When power is applied to tankless, then Green indicator light will show, and continue to show as long as outlet has power

When water tap is turned ON, then tankless unit senses flow of water through unit, and heating begins.
When tankless is heating water, then Red indicator will turn ON.
If red indicator turns on-and-off when no tap is drawing water, then put ear against pipe and listen for water leak.
Fix drips to save money. Install single handle faucets. Do not turn on hot side when using only cold water.
Maybe pushing both up-and-down arrows on remote control will reset error.
Main control at Amazon
RTG20009 18 ga wire wire for remote control

Action if remote shows error code
Error codes 2012
Error codes 2008
Error code 76
How to install Rheem remote control/ pdf
Remote control Wire connection inside tankless
General tankless wiring schematic
How to adjust temperature using remote control/ pdf
Clearing fault history 2008 service manual pg 12
Enter maintenance mode 2008 service manual pg 10

Red shows when tankless is heating water


RTG20009 18 ga wire wire for remote control

Rheem remote control

Add remote control in bathroom

Use 2-wire 18 gauge thermostat wire
Rheem 2nd remote control at Amazon

More useful Stuff

Recall list:

Tankless class action lawsuit
Get your payday loan !!!
Join class action lawsuit against Rheem tankless??
Ron Armstrong may be putting together a class action lawsuit
But wait... you found this webpage  ?!?....
And this webpage was available BEFORE you bought the thing....
So why you didn't research tankless before? Or look at the warranty or parts sheet and ask a question?
Yes you were misinformered when promotional literature says '20 year lifespan.'  Yes it's true that tankless cannot kill bacteria on wash day, but you have bleach. Yes it is true that tankless do not save money long term in most cases. Yes it's true that tankless use more fuel to heat 1 gallon of water. Yes it's true tankless promotion is misleading. But all promotional literature and advertising is foolery. And there are applications where tankless have a role.

Remember. Tankless cost as much as a cheap used car ....  it didn't blow up or kill you.... and imagine telling the jury how you believed that spending lota money to buy a computer-chip water heater that requires larger gas line and larger vent pipe was magically going to supply endless hot water while saving money plus offering trouble-free rainbow of water heating bliss ... when the plumber down the street would tell you not to buy it ... and it's obvious to the jury that you got lota money.
WT (wallet thickness) error
Water conservation Promise of unlimited hot water not consistent with water conservation or energy savings.
Water conservation
Search Fixya questions and answers and chase your tail for hours
Tank logo Pro water heater forum:
How to wire tankless electric
clogged sensor Hidden costs of tankless
Bradford White: "Tankless fall far short of payback"
Tankless cannot be exposed more than 11 grains hard water/ research pdf
All costs are energy: "The genius of tankless is NOT that they save money or energy. Because they don't.
The genius is marketing that targets folks who believe tankless save money and energy."
Read product manual

Maintain water heater 2012/ pdf
Rheem-Tankless Electric-manual.pdf
How to set Rheem tankless temperature 2012/ pdf
How-to-De-lime-tankless/ pdf
Tankless flow rates
Flow Rate
Rheem generally require .4 GPM minimum activation rate of flow and .25 GPM minimum rate of flow to keep heating
Average faucet has 2 gal per minute flow rate Average tub 2.5 gal per minute flow rate
1/2 gallon per minute means: Faucet must fill quart in 30 seconds and gallon in 60 seconds
3/4 gallon per minute means: Faucet must fill quart in 20 seconds and gallon in 80 seconds
See chart: How to test water flow: how far hot water travels in household pipe in 30 seconds
Crossover and Low water pressure can reduce flow rates
Higher thermostat setting can reduce hot water flow when more cold water is added at faucet to moderate temperature.

Water temperature

Hot water

How to change temperature on Rheem tankless water heater greater than 130 degrees F
How to set Rheem tankless temperature 2012/ pdf
How to change temperature on Rheem tankless
How to change temperature on paloma tankless
Or read your manual about dip switches.
Remember if you raise the temperature setting, risk is that tankless cannot heat water fast enough and unit will start throwing error codes and shutting down. If unit is not working at optimal performance, the raising temperature is bad idea.
Add tempering tank to preheat incoming cold water

Larger image

Troubleshoot Bosch tankless
lightning Water heaters are not protected from surge

Tankless water heaters and most other appliances are not protected from surge
This includes tank and tankless water heaters, and refrigerators, microwaves, etc
How to install whole-house surge protector

Tankless are not made in your town

Well nothing is, because you spend your money watching TV, and that never fixed a road or built a bridge, except for the guy who don't live where you do.

Made in America
Probably made in Switzerland, or Cayman islands, or Wyoming
RTG20009 18 ga wire wire for remote control

How to install Rheem remote control/ pdf
How to adjust temperature using remote control/ pdf
Error code 76

Buy whole new tank-type electric water heater for $225
Buy whole new tank-type gas water heater for $350 at local box store

Buy one since it's advertised here... makes sense:
Tankless water heaters at Amazon
Research shows average family of four will save $1-8 on monthly gas bill. That amounts to $12-$96 per year but does not account for cost of installation, required yearly maintenance, cost of repairs, and aggravation associated with expensive water heater that doesn’t work. Plus the dang thing is not made in your town, parts are expensive, and parts are not interchangeable between brands or available at local store.

Reality Check: With tankless, you are connecting complex computer with external sensors to your plumbing and electrical lines and to a gas burner with a vent pipe to outdoors. Plumbing lines, gas burners, vent pipes, and household electrical systems each have plenty of problems without a computer
Pro-n-con tankless
How to wire Tankless electric

Installed it yourself ? Amazing

Changed the dip switches? Took it apart and fixed it?
Gas appliances are dangerous and subject to local and national safety codes.
Protect yourself.
Do NOT store flammables near tankless, or in same room. This is clear fire hazard.
Read product manual. Follow installation requirements, safety advisories, and perform required maintenance.
Provide adequate air supply, and proper venting, and do not expose to flammable vapors.
Improper installation and lack of maintenance will cause error codes.

If you smell gas, leave building immediately and call gas company.

Did you know, if natural gas water heater has dirty combustion parts, that unburned, explosive gas can travel up hot flue pipe. Whoomph.
With propane gas, the gas is heavy and will fill tankless burner, or fall out onto the floor.
Install gas detector at correct height for type of gas.
Bradford White venting .pdf
How to solder copper pipe

Remove flammables away from tankless

Be cautious
Explosion inside your home wastes precious fuel, and could burn down neighbor's garage.

Gas safety cans at Amazon
Tankless save space

Installed behind furnace to save space!!!

Atta boy. Now you're thinking!!?
How you going to work on it?

Who will fix your tankless?

Best wishes for all folks. Rheem tankless
Why do you need a service manual?
... plumber will charge you for service. Each year.

Call for service Don't fix it yourself.

Support the economy:
Hire technician to perform yearly tankless maintenance.
Do your part to support our ecomical situation.
Check your area has has qualified service technicians before buying tankless

Or easily install tank-type heater yourself:
How to install tank-type gas water heater today

Buy a tankless (for the aggravation of it all):
Tankless water heaters at Amazon
Tankless water heaters at Amazon
Z-wave water heater

Control water heater remotely

Control electric water heater with z-wave

Control gas water heater with remote control

Off-peak water heater strategies
Troubleshoot Gas valves with manuals Icon gas valve

How to replace elements

Replace thermostats
How to wire tankless electric

Install point of use water heater
Titan tankless
Anode rods anode rods
Recirculation system Point of use water heater
Type 1 and type 2 surge protection surge protection
Gas and electric water heaters Support the economy:
Buy water heaters  from my associate links:

50 gallon Gas water heaters at Amazon
40 gallon gas water heaters at Amazon
50 gallon Electric water heaters at Amazon
40 gallon electric water heaters at Amazon
Hybrid / heat pump/ water heaters at Amazon

How to install gas water heater
How to install electric water heater
Troubleshoot gas water heater
Troubleshoot electric water heater
Point of use water heaters
Gas and electric water heaters Industrial electric at Amazon

Industrial supplies at Amazon

Industrial and scientific Amazon
Black and Decker

Irwin Hand tools
Klein hand tools
Fluke electrical testing
Dremel hobby tools

Campbell Hausfeld air powered
Tekton automotive
Powerbuilt automotive
Saws and saw blades
box timers Compare box timers

Control water heater w/ Z-wave
Intermatic control centers Control centers:
+ manuals and parts

All control centers and parts

Including Z-wave
Compare programmable timers
Compare countdown timers

Off delay
On delay
Twin timer

Din rail
Control water heater
Enter Amazon from my links

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