My Jenn-Air grill model 720-0336 when you lite one burner it will lite but with low height in flame and as you tun on another flames go to 1/8 inch high as you turn on the last burner than go out. This just began happening I have had the grill for one year. What is going on?

The problem is more than likely, the new tank. More specifically, the way you opened the ODP tank valve. In most cases, it is solvable,

1. Turn the tank valve OFF and disconnect the hose from the tank.

2. Wait 5 minutes and reconnect the hose to the tank.

3. Open the tank valve VERY, VERY SLOWLY (Slow motion. slow). Once the valve is fully open
light the burner farthest from the tank first and turn the burner to HIGH. Did the burner light and
does the flame height look correct? If so, light the remaining burners the same way. Now, do all
the burners light and the flame heights look correct? If so, you solved the problem.

If the above did not solve the problem, you will need to replace the grill's Hose/Regulator Assembly. It's easy to do and you can pickup one at any hardware store or home center that sells gas grills and accessories for about $30.00. Take your old one with you for comparison purposes.

Hope this helped you troubleshoot and solve the problem. Please let me know and Happy Grilling!!

Assuming it's a Propane Grill. More than likely, the grills regulator is partially locked up or the tank is low on gas..If you're confident that the tank has adequate gas, turn the tank valve OFF and disconnect the grill hose/regulator assembly from the tank. Wait 5 minutes and reconnect the hose to the tank. Open the tank valve VERY, VERY, SLOWLY (Slow motion, slow), until it's fully open. Then light the burner that's farthest from the tank, first and turn the flame to it's highest setting. Has the flame height returned to normal? If so, light the remaining burners the same way. Have all the flame heights returned to normal? If so, you solved the problem. Remember to always turn the tank valve ON Very, Very Slowly.

If that didn't solve the problem and you are still sure there's adequate gas in the tank ... You'll need to replace the grill's hose/regulator assembly. You can find one at any home center or hardware store that sells gas grills and accessories. Just make sure to take your old one with you for comparison purposes.

Hope this helped you solve the problem and Happy Grilling!!

If you're confident that you have adequate gas in the tank. turn the tank valve OFF and disconnect the hose from the tank. Wait 5 minutes and reconnect the hose to the tank. Once connected, open the tank valve VERY, VERY SLOWLY (Slow motion, slow). Once the valve is fully open, light the burner farthest from the tank first and turn it to it's highest setting. Does the flame height look correct? If so, light the remaining burners the same way. Do all the flame heights now look correct? If so, you solved the problem. Remember to always open the tank valve very, very slowly.

If the above didn't solve the problem, you are either low on gas or the hose/regulator assembly needs to be replaced. If replacement is necessary, you can find the hose/regulator assembly at any home center or hardware store that sells gas grills and accessories. Take your old one with you for comparison purposes.

Hope this helped you solve the problem. Happy Grilling!!

After you disconnect the hose from the tank, wait 5 minutes before reconnecting it. Then turn the tank valve ON VERY, VERY SLOWLY (slow motion, slow). Once the valve is fully open. Light the burner and turn it to it's highest setting. Did the flame height return to normal? I f so, problem solved. If it didn't remove and clean the burner and the venturi valve, Spiders like to build nest in them. If after all of this, the flame height still hasn't returned to normal and you're sure you have a good amount of gas in the tank. You'll need to replace the grill's hose/regulator assembly. You can find one at any home center or hardware store that sell gas grills and accessories. Take you old one with you for comparison purposes.

Hope this time, Your problem was solved. Happy Grilling!!

Replace the regulator that should do it

This seems to be a problem for most Jenn-Air users. The burners are defective, rusted or clogged and allowing the flame to "back up." You most likely have a melted electronic ignitor as well as gas valve damage. The new burners that I received this week for my model 720-0061-LP are 1/2 inch shorter than previous versions. Time will tell if this fixed the problem. I would call Nexgrill and get all new burners and inspect the gas valve area for damage. Since 2004, I am on my 5th set of burners, glad they were free since I have a lifetime warranty on my model.

close your air vent on the burners it will increase the height of the flame

Turn on one burner to start, once it is on, turn on a second burner. If the flame gets lower with two burners on, you need to replace your regulator.

it sounds like it is a natural gas grill instead of propane change out your orifices

it appears that the air intake intake is incorrectly set or you have the incorrect gas jets fitted to the product. Regards Engineer