[ruscar]

Hi,
I have a 17-year old Thermador Professional Rangetop, model number GCT48 4GG, that I have owned since it was new, on which the grill is now functioning erratically. When I first turn on the grill (to the highest setting) the glow plug heats up and about 30 seconds later the gas valve opens and the burner lights fully—all as it should be—but after about 5 seconds the gas shuts off then turns back on again after 10 seconds or so but only at about half flow rate this time. This on-off cycle continues for 10-15 minutes before the gas finally stays on continuously, but only at a reduced flow rate, so the grill never gets fully hot, only medium at most no matter what setting I set on the dial.
I have taken the grill apart, thoroughly cleaned and inspected it, and everything looks to be in good condition, but it stills functions as described. The glow plug seems to be getting fully hot, both the inner and outer parts of the tip. I suspect that the grill safety valve might be malfunctioning, but would like to hear from the experts their opinions.
Thanks.

[Gene]

Most likely the problem is a bad gas safety valve. I would replace the igniter as well to make the repair more relaible.

- The gas safety valve Part number: AP2832925




- The igniter Part number: AP3674290




Here are the breakdown diagrams and Replacement parts for THERMADOR GCT484GG | AppliancePartsPros.com

Gene.

[ruscar]

Thanks Gene. I believe you, since you agree with me, ha!

The safety valve you show does not look exactly like the oem valve on the grill. The difference is that the inlet port (large coupling) is on the side of mine, which would be pointed directly at you in the picture of the replacement part you recommended, as opposed to coming out the top (to the right side of that picture).


Do you know where I can get the correctly configured valve? I have been unable to locate one so far, which means I would also have to replace the tubing between the regulator and the safety valve. The codes on the side of the original are on three lines, as follows:

8940

NC-4125-5

16003-V

Thanks again.


Russ

[Gene]

Russ,

The gas safety valve with the part number AP2832925 came up as a search result for the model number you posted. This is the OEM part recommended by the manufacturer.

Gene.

[ruscar]

Thanks, Gene.
I agree—that's the part that shows up in all my searches for a replacement too, but it doesn't match the one that came with the grill originally. I have not been able to find one that matches it using any search criteria I can think of. I guess the best thing to do now is order tubing that will reach up and around to the inlet port on top of that replacement part, since I am very reluctant to try bending the existing tube to reach that location for fear of breaking it.
Thanks again for your help, Gene.

[Gene]

I double checked the diagram



and found there two burners, #30 and #31. They have different gas safety valves, #29 and #33. The gas safety valve with the reference number 29 has been discontinued and is no longer available.

If this is the part you needed, call the Appliance Parts Pros customer service and they might get one for you because the data base shows one available (if there is no errors).

The other valve is still available and the part number I posted earlier.

Gene.