Performance ratings for gas hot water heaters? Where can I obtain said info?

First thing did you open all the shut off valves in the water lines going to or from the heater. I shut one off one day and forgot to open it up. Frustration was the word.
Check for air locks in the tank and or pipes.
Do you have galvanized pipes or copper? Old galvanized can plug up with rust. Is there a filter in your system?Filters can plug up.

Todd, Check the attached links,instruction and guides for water heater thermocouple and gas valve. Good luck
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Hot Water Heaters How to Install Thermocouple on Water Heater

http://www.familyhandyman.com/plumbing/water-heater/how-to-replace-a-water-heater-thermocouple/view-all

CTRL TV Volume 1 Introduction to the problem and troubleshooting Gas Water...

gas water heater parts diagram Google Search

Mark, It sounds like the gas valve may be bad. You may want a tech to diagnose and repair.There are other things to check also air intake and exhaust must not be plugged and the exhaust fan must be operational if equipped.
Check the attached links,instruction and guides, Good luck
"I hope this helped you out, if so let me know by pressing the helpful button. Check out some of my other posts if you need more tips and info."
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Gas Hot Water Heater Repairs
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You probably need commercial 150gallon gas water heater.
Or three 80 gallon tanks, depending on number of people.

80 gallon residential gas heater is rated for low-demand 6-8 person household.
80 gallon residential electric is rated for low-demand 5 person household

80 gallon is not correct for 14-28 people in 7 apartments
http://waterheatertimer.org/Whatsize2.html
http://waterheatertimer.org/Two-water-heaters.html

Call local plumber, or local code department.

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

Replace gas control valve.
The gas valve is the thermostat.

Vacation setting should be 50 degrees, or so, depending on exact gas control valve.
If gas water heater is not responding to temperature setting, then thermostat is suspect.

Open following link to help identify tank-type gas valve.
http://waterheatertimer.org/How-to-adjust-water-heater-temperature.html
Each gas valve should have identifying number on side.

Instructions how to replace typical gas control:
http://waterheatertimer.org/pdf/White-rodgers-gas-vale-replacement.pdf
http://waterheatertimer.org/pdf/How-to-replace-gas-control.pdf

Additional resources with service manuals:
http://waterheatertimer.org/How-to-install-gas-water-heater.html#troubleshoot

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A2 error on your Bosch water heater means "Fault in the flue gas limiter"

This can be caused by several things:
The gasket on the flue gas collector may be dislodged/leaking.
Check/Remove/Reseat the gasket.
It will not reset until about a two hour cool down.

Also - check the overheat sensor fuse wire - it may have gotten hot and melted the jacket and/or been dis-colored.

Finally - there is a retrofit kit "repair" that can be obtained by calling them directly.

1-800-642-3111 and request the "FLUE GAS LIMITER RETROFIT", Part NO. 8-700-400-032. This should solve many error code situations and get you on your way again.


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LP pressure needed is no less than 11 inches of water column while all gas appliances are in operation. Info is in the installation manual near checking CO2 levels.

check your voltage rating on info plate on unit,agains't what's coming in.confirm wire connection's are 100% at wtr/htr .access the thermostat's and verify,that they are turned up to a set temp,i.e. so low it won't register.a few thing's to look at.good luck.

Power outage will reset Rinnai unit to that temperature. Read manual for more info.

Ok the way this system works is from a pressure and flow switch. The pressure switch picks up the slight drop in pressure when the hot side water is turned on then turns on the burner. The flow switch measures the amount of water flowing and adjusts the size of the burner to the amount of water flow. So a couple different things might be happening. The flow switch might be sticking causing the water heater to throttle down the burner but not off when the water flow is off. Or the gas control valve might be by-passing gas when off causing the burner to stay on even when the demand is off. Run the hot water on high demand then turn the water off. If the burner is still on try banging on the water heater with your hand and see if the burner shuts off completely. If it does the gas control valve might be by-passing. You would also need to check and see if the pressure/flow switch is giving any voltage signal changes when the water flow is off. These tankless water heaters are more comlplicated to work on than a standard water heater and you may need a professional's help...good luck