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Condensation getting error code 25. brand new heater. no blockage with condensate drain. What is a air gap as suggested in your trouble shoot procedures for code 25

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Disconnected condensation drain on hot water heater.

Tankless or hybrid water heater?

Tankless gas must have special fitting between water heater and vent that has a condensate line fitting. Hot toxic vent gasses traveling up vent pipe cause acidic water vapor to form inside vent pipe that drips back down vent and drips onto heat exchanger and other parts eventually burning hole through expensive metal alloy heat exchanger, rendering tankless computer water heater useless after electric circuitry gets wet and shorts out.

Hybrid or heat pump type computer water heaters must have condensate drain connected to catch pan located just above storage tank and below compressor. Condensation can form on condenser coils and drip into catch pan where there is primary and secondary drain

Read product manual

Apr 17, 2014 | Water Heaters

1 Answer

Burner time reset.

Are you sure you have an NR71? or is it an NRC model? only NRC models should be getting that code. Anyways, your house water treatment system has nothing to do with the neutralizer. The Neutralizer that it is telling you to replace is not there to treat the water going to your house. It is neutralizing the acidic condensate produced by the exhaust in your "condensing" unit. Without a new Neutralizer the condensate that drains out the bottom of the unit will be strong enough to kill plants and eat away very slowly at some items or metals underneath the skinny condensate drain. It's not a big deal unless you have the unit sitting above something you really care about and there's no condensate drain pipe attached. Either way, if you buy a new Neutralizer it comes with instructions on how to reset the timer so that you don't have to have the EC 92 bug you anymore.

Nov 14, 2013 | Noritz 7.1 Gpm Natural Ng Gas Tankless Hot...

1 Answer

No condensate coming out of the condensate drain just blows out air

Call Rheem and they will recommend calling installer since tankless computers are non intended as do-it-yourself.
If condensate drain is blowing out 'air' do not forget this air is deadly poison CO gas and will kill you, first giving you a headache that goes away when you are out of house. Remove affected people from home and put into fresh air and lay on side, never on back or they will suffocate. Call 911 immediately and most will recover.
Copy following link for resources and required maintenance for tankless computers that heat water: scroll down to venting and manuals and review each to check how vent lines are set up, and that condensate line is set correctly. However this information is NOT guaranteed to match each model made by Rheem as they advance their product marketing strategy to exclude as much safety information as possible for do-it-yourselfers.
Condensate lines can clog over time. Clean line with compressed air, and soak in clorox, and swing around overhead to remove anything inside line. This line contains bacteria so do it in neighbor's yard.
Not all conditions produce vent condensate. Condensate might not form in vent line if weather is dry and the vent has good draft. But later when conditions change, condensate might begin flowing.
Condensate is caused from burning hydrocarbon fossil fuels in any gas appliance. But problem is bigger with tankless since these appliance consume so much fuel per heating event since tankless are required to heat water rapidly as water passes by in a pipe. This is why tankless require larger incoming gas line, and larger vent line made from specific materials for the vent.
Among the long list of poisonous by-products being vented outdoors into the air our planet breathes is acidic water vapor. If conditions are such that the vapor condenses before reaching outdoor, then the acidic water gathers in the vent line and rolls back toward the tankless computer, and goes down into the condensate drain and then down into your pluming drain where it can corrode pipes and add acid by-product to other environments.
If the acidic water is allowed to fall back into tankless heat exchanger instead of down condensate drain, then eventually it will chew a hole through the special nickle alloy heat exchanger (imagine the hole it will chew through household drain lines), and the surprise will not be evident for a few years until leak develops and the tankless exchanger must be replaced at great expense, plus repairs to shorted motherboard and electrical sensors.
Just don't install tankless computer water heater is best solution for myriad of problems, maintenance, and expense of owning a device that must immediately monitor incoming and outgoing water temperatures and flow rates, incoming gas flow rate and pressure, outgoing vent flow and pressure, interact with a remote control device, while monitoring burn rates and combustion temperature using a computer motherboard that is not protected from line interference or power surge, etc
Just install tank-type heater:

Aug 18, 2013 | Rheem RTGH-84DVP Condensing Tankless Water...

1 Answer

How do you fix rinnai tankless water heater code 79

Do not spend 500 on plumber to determine that condensate drain was not installed properly on vent line, and that acidic water from combustion by-product has been dripping down into tankless and burning hole through the special-alloy heat exchanger instead of going down into floor drain and corroding your plumbing pipes.
Do not spend hours fulfilling the required monthly and yearly maintenance, or spend money on service call each year to get the burner cleaned and gas pressure checked on your tankless computer that heats water...
Instead, fix any tankless problem, any brand tankless, same day do-it-yourself for $385, by replacing 1 part: the whole thing:
Do not install tankless.

Jul 20, 2013 | Rinnai Water Heaters

1 Answer

Where is the drain pan located?

Sometimes there is no condensate.
Sometimes the drain line is clogged.
Copy following links for GE Heat Pump water heater.
Expanded drawing of 2012 GE heat pump condensation drain reservoir
Clean the drain line by swinging over head.

Sep 11, 2012 | Water Heaters

1 Answer

Rheem-Tankless-water-heater I am showing a C2 then 11 flashing on my thermostate. what is wrong.

Before calling service technician, open following links for common error codes, Rheem chat, and possible manual.

Error codes are start point for troubleshoot.
C2 11 is 'no ignition' or 'gas shut off vale is not open'
Gas shut off valve handle must sit parallel with gas line.
This kind of error code can be air in gas line, improper grounding at electrical outlet, bad igniter, shorted solenoid, loose connections, etc.
Most tankless manuals recommend yearly service, and that type of work usually covers cause for most common error codes: for example checking gas pressure, gas line, air in gas line, clean and check burner and combustion parts and igniter, inspect that vent condensate is properly draining and vent has good draft, clean water filter, clean air intake, check for loose wires, delime heat exchanger, test outlet with circuit analyzer etc.

Aug 11, 2011 | Water Heaters

1 Answer

Every time it rains our instantanious hot water system comes up with error C9 and C12

Before calling service technician, open following link for Rheem troubleshooting resources including contact and chat and typical manuals:

Error codes are start points for troubleshooting and can include long list of things including multiple causes.
Error code 12 shows 'condensation collar' and 'vent lengths' which are associated with the vent to outdoors. Changes in air pressure during low-pressure rain events MIGHT affect the venting and cause tankless not to ignite, and MIGHT cause excessive condensation. Improper condensation can rust out the heat exchanger without showing any signs of problem until the unit is ruined.
C9 is not listed. Contact Rheem, and then add a comment saying what Rheem suggests as solution for C9 error. This will help others in the community with same-similar problem.

Instruction manual recommends yearly maintenance by qualified service technician.
This maintenance would usually check all things shown in error 12.

Jul 18, 2011 | Rheem Tankless Hot Water Heater...

1 Answer

My ariston boiler is not working it just shows A 01 have reset but still nothing any ideas?

Basic checks:-
water pressure in boiler
gas supply on
Turn boiler on then:-
does the fan come on - u can hear this at the top of boiler
does the gas valve click on
has there been a burning smell near the lower front [check the pcb]
check the co-axial flue is ok with no gaps between inner & outer [rare but not unknown]
If it's a condensating boiler check the condensate outlet tube for ice blockage especially in current weather

Dec 27, 2009 | Water Heaters

5 Answers

Rinnai tankless water heater code 12

12 - Flame Failure or Poor Ground

1. Immediate code 12 is usually a defective gas valve, power supply problem, or defective fan motor wiring harness.

2. If code 12 occurs after a few seconds it indicates that proper operation was established, but then stopped unexpectedly.

3. Verify that fuel is being supplied to the unit.

4. Check for proper electrical ground. Unit must use a grounded power supply.

5. Check for flue blockage on inlet or exhaust.

Dec 31, 2008 | Rinnai Webstone The isolator EXP tankless...

7 Answers

Rheem RTG 53 PVN with fault codes C4 or C7

I had the same problem with my tankless waterheater (flashing c4 76 alternately). I called Rheem
tech support and they had me 1 power down the remotepanel 2 unplug the unit from the wall 3 remove the cover 4 remove the wires for the remote panel from the circuit board and pull the twisted pair that goes to the remote out from the bottom of the unit. 5 reinstall the cover 6 plug the unit back
into the wall and turn on the hot water see if it works. It did in my case and they are sending me a new remote panel. I hope it helps.........

Nov 21, 2008 | Rheem RTG-53PVN Indoor Natural Gas...

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