Gas exhaust smell when Hot water heater ignites

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
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Unless you are using a tankless hot water heater, there is a limited amount of hot water available in the tank. Electric and gas water tanks need time to recover after use, and if you are using heavily, it can exhaust the available supply. That said, there are a couple reasons why you may have less hot water than seems normal. In both electric and gas water heaters, silt can form in the bottom of the tank. This will build up over time and displace water. It also reduces the heating efficiency of gas units. There is a drain valve on the bottom of water heater tanks to allow for purging of this silt periodically, but few ever do it. You could also have, in the case of an electric hot water heater, a bad element or thermostat. Most electric heaters have an upper and lower element and thermostat. If one fails the other will still work, but the water takes longer to get hot and will deplete faster.

check first if you have good water flow to and from heater. lift pressure release valve on inlet and allow few sec to flow, same with outlet hot water safety valve.

remove front cover from the heater, you should see your gas connection and thermostat knob.

check if gas is burning evenly and on whole surface, check for leaks on the heater and on the lines to and from the heater.

if you did not find any faults, no leaks, safety valves work correctly, check thermostats settings,

wind it down to minimal, then turn it to about 1/4 value (you did not specify model but this should do, widening arrow or numerical values ar self explanatory), lift hot water safety valve for few seconds, then open any hot water tap (faucet if you are an american...) and check if gas ignites and burns.

set thermostat to about 2/3 value and again, lift hot water safety valve for few seconds, then open any hot water tap. check if gas ignites and if water is sufficiently hot, if too hot - wind it down to say 1/2 way, if too cold, wind it till resistant and then back off a bit, DO NOT EVER LEAVE VALVE OR THERMOSTAT ON MAX!.

if none of these help - you need either, change the thermostat or heater itself.

if works - you solved the problem, close the tap, close the cover and use the system as you normally do.

i am always recommending use of insulation on the hot water system, it saves heaps of money over the life of the system.

hope this will help you - do not forget to vote... :-)

No. A water heater is a sealed system it needs to be addressed for the original problem. High sulfur content has been a complaint as far as smell,and I remove the anode and replace with a brass plug because of. Shallow wells in the area largest complaints.

here's what Bradford White lists....
Burner Will Not Ignite
REASON REMEDY Excess primary air Adjust air shutter to reduce air supply -- if supplied No gas Check with utility Dirt in main burner orifice Clean orifice -- check for source of dirt and eliminate Dirt in gas lines Notify utility -- install dirt trap in gas line Venturi clogged Clean -- check for source of trouble and correct Pilot line clogged Clean -- check for source of trouble and correct Main burner line clogged Clean -- check for source of trouble and correct Defective thermocouple lead Replace with new thermocouple lead Defective thermostat Replace Defective magnetic valve Replace entire control Thermostat set too low Turn temperature knob to desired temperature Heater installed in confined space Provide ventilation by use of louvers in wall or door time for a service tech.

water getting hot should be almost instant... it may take a minute to move the cold out of the pipes.
is your heater ignighting?
if not then you might have a small amount of air in the gas line when you changed the bottle.
you will need to bleed the line...

with the gas turned on, loosen the gas connection to the unit and let the air out until you smell gas.
tighten the connection, snug, do not over tighten.
wait about 5 minutes for the gas to dissipate before attempting to light the unit.
during this time, you can use a little soap water on the connection you loosened to make sure it is not leaking.

now go turn on your faucets, let the water run for a minute and make sure you get hot water.

if no hot water, then you might have something else wrong. you will need to let us know the error code and what the unit is doing

try to remove pipe you could have a clog water,ice,nest. also you may have a bad pressure swith hose find the hose and **** to see if it will fire
also if you take your pipe of you make turn on to see if you get fire you can not run for more then 30 sec with this off co. will fill the house.

the system was not sized properly, you need to have a 3/4 gas line to the unit for the volume of gas it needs, the tankless water heaters need to have every bit of gas that is says, it sounds like who ever installed di not make sure you had enough gas comming in the house, you might have to either have a new meter installed or run the gas lind directly from the meter to the water heater and cap off the gas line thats there

yes, provided there is no excessive build up. The gas and air mix must be right before the mixture will ignit. a household stove will do this each time it's turned on. That's why yhe igniter sparkk hits about three times before it lights. proper venting will confine any fumes to the cimbustion chamber to be carried out the exhaust. If the odor is strong then have the appliance checked for safety sake.

What type of heater is this? I need to know the model name and make and then we can go threw the process of how to do it. Most gas heaters do not have power to them and I only know of a few tankless heaters that do.