“Hey you, in there, Mr. Big Burner! Wake up! Where are your flames?”

My oven had been turning on for a few weeks. Ever since a Pacific Gas & Electric (PG&E) tech had examined it, everything turned on and the tech made sure the stove was operationally sound.

But after a few weeks, the oven stopped lighting. The cooktop burners were working so I knew the stove was getting gas. I didn’t yet understand how the whole oven system worked yet, but I was determined to learn.

There were some oven relighting tips enameled on the Grillevator door inside panel (so vintage-y cool), but they didn’t make much sense to me at the time. I’d seen and read them many times but had no idea what they were really about.

 

Oven And Broiler Pilot Lighting Instructions, For Nat. Mfg. And Mixed Gases. Light Pilot, Wait 45 Seconds, Push Red Buttons Located Under Cooking Tops.

For L.P. Gases Push Red Button In Firmly And Hold, Light Pilot, Wait 45 Seconds, Release Set Safety Buttons Located Under Cooking Tops.

Mixed gases? Red buttons? Under the cooking tops? How do I get under the tops? Is the red button different than the safety one?

Clear as mud. Aaarrrggghh! But those tips were the only ones I had to go on.

[Deep breaths] Since I had a backup countertop oven, I didn’t need the OKM oven right away. I decided to deal with all the stove oven troubleshooting later. Deep cleaning my OKM stove really helped me learn a lot more about it’s layout, including how to get under the cooktop (so easy) and where the red buttons were.

Gas safety valves were located way in the back under the cooktop. Left one for the Grillevator broiler; right one for the oven.

But if I was to better manage my stove and troubleshoot my oven’s operation, there was still a lot I wanted to learn.
Resetting the safety valves

Resetting the safety valves

One key thing; whenever the gas is shutoff to the stove, the pilot flames die, which causes the safety valves to close. I knew all the pilot burners needed to be relit whenever I turned the gas back on. The cooktop burners would then be ready to turn on. But the safety valves had to be manually opened before the oven and broiler would work. The steps I take:

1. Open the stove’s shutoff valve; get that gas flowing!
2. Make sure all the pilot burners are lit. My stove has two under the cooktop, one in the oven mounted next the thermocouple and main burner, the other is in the Grillevator broiler, next to thermocouple and main burner.
3. Remove the four burner grates so the cooktop can be lifted up (like lifting up the hood of a car).
4. Wait a minute or two for the pilot flame to heat up the thermocouple sensor.
5. Push in and hold the red button of the oven’s safety valve. Pushing  the red button manually opens the valve and allows the gas to flow to the main burner.
6. Turn on the oven. The oven pilot flame will ignite the main burner gas. Release the safety valve buttons. The safety valves should remain open until the gas to the entire stove is turned off. The red button should spring back to its original position, whether the safety is open or not. If the oven burner flames die again, the safety valve closed again. 🙁

 

Once I started really working on my stove; repairing or replacing parts, tweaking the cooktop burners, etc. for safety sake, I’d frequently turn off the gas to the stove to be safe. So I relit the pilot burners and reset the safeties a lot.

Dead Thermocouple

Then one day I turned on the oven – no oven burner flames!

I went through those relight steps doing the safety valves and everything. The oven burner flames came on for a few seconds, then died. I thought I did everything I was supposed to. What happened?

A vintage stove technician tested the thermocouple voltage and informed me its voltage was too low, so he replaced it. The oven worked, again! I was left to ponder WTH a thermocouple was and what it had to do with anything. 🙂 I wasn’t going to ask the technician. He charged by the hour.

So it seemed there were a few points of failure with my oven’s performance.

Oven Lighting System

Over the next few months, I slowly learned my stove’s gas plumbing system was a little complex, all new to me, but quite logical.

A view of my stove underneath the cooktop.

My oven’s operational success was dependent on several things working:

Robertshaw oven thermostat heat control valve; its a valve attached to the manifold and allows gas to pass thru it. Its long capillary sensor inside the oven, it determines and regulates the temp so it stays within the range of the set temperature. But as far as gas flow is concerned, it simply needs to open enough to let the gas pass through. Easy peasy.

solenoid valve: my stove’s oven plumbing also has a valve. It looks like a little box. It’s electronically connected to the clock. It’s the next valve in the oven’s gas supply line, after the oven thermostat. If the clock is set to the right mode, it sends a signal to the solenoid, the solenoid closes until the clock tells it to open. I keep the clock setting to Manual(M) which tells the solenoid to remain open.

safety valve; the oven’s safety valve is the next valve is sequence for the gas flow to the oven, after the solenoid. It’s the thing with the red button! If conditions are not right, it will close, blocking the gas at that point. The safety valve electronically connects to a thermocouple. If the thermocouple gets too cold even sitting near the pilot flame, it can’t send a strong enough signal to the safety valve to stay open so the valve closes.

oven pilot burner; it’s a separate little burner with its own gas supply from the manifold. Conveniently, it acts in place of a 24/7/365 lit match. It helps the main burner to ignite. It sits right next to the thermocouple and main burner, but has it’s own gas supply.

Safety valve with connection to thermocouple wire. This end of the thermocouple screws into the safety valve.

thermocouple; it is electronically connected to the safety valve. The other end of the thermocouple sits in the oven, next the the main burner and the oven pilot burner. The pilot heats the thermocouple 24/7/365. Heat causes the thermocouple to generate a voltage (like a small battery). That voltage is 15 millivolts d.c. at the highest temperature. Voltage decreases as the temperature decreases. The power travels to the safety valve, telling it to *remain* open.

Troubleshooting my gas oven

Now, with a solid understanding of my oven’s operational system. I can diagnose problems with the best of them. 😀

Provided the thermostat simply opens when I turn the dial, I learned there are several points of failure, behind the scenes, in my gas oven system that can prevent the gas from flowing to the oven burner. Some failures are more likely than others; some are easier to deal with than others.

E) Finally, just make sure your stove’s gas shutoff valve is open.

When the valve knob is parallel to the gas hose, it’s open, When perpendicular to the gas hose flow direction, it’s closed, blocking the gas flow. Whenever there is an unknown problem with my gas stove, the ultimate gesture is to close the gas flow to the stove, until the problem can be determined.

And of course, if any of this troubleshooting scares you, by all means let a professional handle it. Try locating a master plumber who does gas plumbing as well as water plumbing.