Gas ignites flame but water is not getting hot

1. Open the up the door or the cover over where the pilot light is accessed and also located at . The pilot light will be located under the gas valve and some water heaters just have an open gap instead where you can see the pilot lights burner is.
2. Using either a flashlight or a headlamp to find out where the burner i located inside. 2 small gas tubes will lead to it. You will want to watch it as you are working.
3. Turn the gas knob to "Pilot,"and then press and hold it down. This will begin to start the flow of gas so you can light the flame. Some water heaters do have a separate button for pilot mode, mostly it will be a colored red one which you will have to press and hold.
4. While still holding the gas down light that pilot. Some water heaters do have a red or black igniting button and some others will have to be lit manually with a lighter than is longer.
5. When the flames do ignite continue to hold the gas knob or button down for a full one minute. Then slowly release it and make sure that the light is still lit and is still on.
6. Turn the gas knob to On and then listen for the distinct "whump" or whooshing sound of the main burner igniting.
7. Replace the cover.

check gas shut off valve make sure it is on -sounds like a bad thermocouple which is a safety that is connected to the gas valve if the thermocouple doesnt read a pilot lite / flame will shut valve off the link can assist you but if your going to diy this yourself ----use extreme caution and safety around any gas units
How to Replace Water Heater Thermocouple or Flame Sensor

If this is in a RV the propane monitoring valve may require more gas flow to turn on than the water heater requires. A central heating system requires substantial gas flow so when the monitoring valve opens to fire the central heating, there is enough gas flow to also fire the water heater.

http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#igniter

http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html#intellivent

Gene h

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

Tell me more! --
Do you have any other gas appliances in the house?-- and they are firing OK? Can you hear the gas flowing when you push in on the ignition start button? -- There should be a spark as you 'snap' the button?
Remember-- YOu get no ignition of the big flame, until you have water flowing--
How old is the heater?-- Could there be come obstruction in the water flow sensing device?

Parts list:
http://www.hotwater.com/lit/partslists/197728-004.pdf
Flame rod, flame sensor sits next to igniter inside combustion chamber. This can be cleaned with sandpaper. Do not touch with fingers. Purpose of flame rod is to detect whether ignition has caused actual, sustainable fire inside the combustion chamber.
If sensor is bad, or no ignition is detected after 2-3 attempts, then 'no ignition' error is given.
Bad gas control valve, bad-or-dirty flame rod-sensor, low gas pressure, misaligned rod, dirty combustion parts, etc

Service handbook:
http://www.hotwater.com/lit/training/316586.pdf
High gas pressure spikes can daMAGE gas control valve p7

Product manual:
http://www.hotwater.com/lit/im/com_gas/197727.pdf
Word-search for 'failure'
Low gas pressure. p14 and p54
1-3 trials before declaring 'ignition failure. p48
bad flame sensor (clean with sandpaper) #10 p58
unit must be grounded (check outlet with circuit analyzer) #12 p58
Sequence flow chart p59
Rough starts = ignition failure p60
Troubleshoot chart - ignition failure p62

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

Call Bosch
Gas Products Technical Support: 800-642-3111

That model number is only shown at one website, and that model number is not shown at Bosch.
Open following link for Bosch:
http://www.boschwaterheater.com/BoschHotWatercomHome/GasProducts/tabid/331/Default.aspx
Search of Bosch for that model number shows no result.

Some water heaters do not have a pilot light. Instead they use hot surface igniter rod that glows red hot
The igniter rod ignites the gas after solenoid valve opens and gas flows to combustion chamber.
The igniter rod and heat sensor have to be operational, and have to be positioned correctly for ignition to take place.
If igniter rod is not working, or if heat sensor does not detect flame, then gas solenoid valve shuts down and water heater does not heat water.

Hi,
These hot water heaters will drive ya nuts!!! They are great when they work but a bugger to work on...
The problem may actually be the flow sensor...often they fail to sense the flow and then do not ignite....
Is it actually trying to ignite the flame???
Is the flow switch turning the heater on?
If it is trying to ignite, do you have spark?
Does the pilot light at all?
Is the flame sensor clean?
Is power going back to the control?
Is the control failing to provide power to the gas valve(s)?

All these things need to be gone through and checked off...this will get you started towards finding the trouble...

heatman101

You won't see any red glow until the burner ignites and burns for a while. Its only an ignitor and flame sensor, not a glow plug style.The ignitor has to provide spark for gas to ignite, then it also senses the flame and keeps gas flow coming. What exactly is happening when you turn it to on?

you need to replace the thermocouple its an electronic device that keep the gas flowing . the pilot light is always on and the thermo couple controls the flame. if it goes bad the flame goes out and the burner wont come on to heat the water, they are easy to replace and available at all home depot or a lowes kind of store.