Kitchen Gas Appliances - Vintage Roper Wall Oven T-Stat Needed

Greetings All,
I have a stainless steel Roper wall mounted cooking oven that won't keep the standby pilot lit. It uses a Robertshaw VC4400 series thermostat (not original) with standby and heater pilot adjustments. This is a very simple control that uses a capillary to turn the heater pilot on and off heating a safety capillary to turn the main burner on and off to maintain temp. The heater pilot adjustment works fine but the pilot adjustment does nothing and the flame is so small that a small draft (like opening the oven door) will blow it out. My guess is something blocking the pilot orifice but I can't seem to get it clean (using compressed air). I tried to purchase another valve but I'm told they are obsolete and unless you're a contractor the parts supply doesn't want to give you the time of day. Surely someone makes something I can use as a replacement (I don't mind doing some modifications). I've thought about putting some solvent into the passages but I'm afraid there my be some rubber diaphrams of other parts that might be damaged.
Suggestions please....

Hello: L G Christianson. Welcome to my Gas Appliances forum.

I cannot fathom the idea that a retailer can afford to turn away a retail sale of an oven thermostat, yet some CRY about the overhead and the bottom line. But that's another whole story.

If your local retail dealer does not have or won't order or sell you at least a compatible part, try another dealer out of the area, if need be.

Try ordering at the direct online RShaw web site or phone calling.
Visit our own parts web site.
{Scroll way down this web page to our own members hardware store}
Visit Jeff1's forums for Electric Appliances.
Also check our paid advertisers web site.

You might want to disassemble the part and clear the orifice manually. Use a pipe cleaners thinest wire. {there are 2 wires in each} A pin often works too but be aware, the opening is EXTREMELY tiny.

Often times air pressure will not clear out the corrosion. The only CAUTION here is not to enlarge the orifice hole or slot. It's extremely tiny.

TIPS:
Use a magnifing glass and a bright light to visually see the opening, if needed.

Work slowly and carefully. Any mistakes may not be correctable.

Regards & Good Luck
Gas Appliances Forum Moderator
Tom_Bart........Fast, Fair, Friendly & Highly Efficient......:D
TCB4U2B2B.....Company Enterprises.
Energy Conservation Consultanting & Natural Gas Appliance Problem Diagnostics Technician Services.

Hi Tom, thanks for the reply.
I've disassembled the control as far as I could and the remainder appears to be press fit. The pilot adjustment is not by a needle valve but some other type of valve unknown to me (looks like it pushes on some type of diaphram). I've even left messages with Robertshaws' customer service dept to see if a replacement is available but they didn't bother returning my call (not surprising these days with streamlined service departments). I can't afford a new oven right now and have a house full of kids so I will find a solution if I have to build something myself (needle valve and separate pilot comes to mind).

YOUR ABSOLUTELY CORRECT ABOUT NO CUSTOMER SERVICE

I HAVE THAT SAME PROBLEM MYSELF...:mad:

I have to say that I have offered you about every bit of possible solutions I can think of at this time. I surely hope your willing to explore the other possibilities offered.

WAIT! One more possibility came to mind...:)

Check the pilot orifices too. May not be a thermostat problem. Those tiny holes/slots in the pilot orifices corrode up as well. Same cleaning and clearing method is used.

Good Luck,
Tom_B

Tom,
Actually there is only one pilot but it has two modes. Normal mode is the standard pilot where it remains until the temp dial is turned on and up. At that point the second mode (heater pilot)kicks in and the pilot flame gets much larger and hits the thermal couple that activates the safety valve (just turns the burner on until tstat reaches temp and shuts off flow to the heater pilot). This continues as long as the tstat remains in the on position. If I tee off of the pilot tubing going to the tstat, insert a needle valve and tee off the other end to the pilot I can bypass the internal standing pilot and create my own.... what do you think?
Larry

Hi: Larry

The quick and dirty answer to your question is: NO

The larger pilot flame or increased in size pilot is an "Actuacting Pilot Flame." This type does not heat a thermocouple. It heats a "Fluid Safety."

For the benefit of anyone reading this reply posting, it's important to know the difference and equally as important to know that there are 2 different types of "Fluid Safety" Systems.

1 type uses fluid pressure to open the gas valve directly, while the other type uses fluid pressure to make an electrical connection.

The fluid safety that makes an electrical connection is called a "Flame Switch." This type uses full 120 volts of AMERICAN house current. The electrical power must be turned OFF before attempt any replacement of this type of safety part.

Larry. The type of safety element in your oven is a Fluid Safety. Care must be taken to install a replacement part correctly. Over tightening it into the gas valve will bypass the safety and render it useless, exposing the appliance, kitchen and possibly the entire house to fire or explosion danger.

If have posted a prior FYI topic on this subject in the prior postings within the forum on the topic. Check it out. Have to exit here to check other forum questions, tend to behind the scenes activities, functions, duties, etc.

Regards and Good Luck,
USA VET 2