These, are off of an old Mueller #10. any ideas on what I can replace this valve with? also, the reg

dmbg1

EdTheHeaterMan

That design valve for small residential heating equipment is considered obsolete. There are valves that can replace that one but do you want the liability associates with your choice?

Show a photo of the entire control wiring system and perhaps a wiring diagram if it is posted on the appliance, then perhaps someone has some options for you.

I did find this info, but no wiring diagram of gas train details here

https://archive.org/details/MuellerClimatrol/page/n12/mode/1up

I believe the 5 refers to the size and the -W refers to water (as opposed to Steam)

EdTheHeaterMan

Here is a diagram of control system that you may have.

You can clearly see that the pilot gas does not come from a combination gas valve like the valves used today. There may be a pilot sensing component to the main valve. If the pilot blows out, then a thermocouple will not allow the main valve to open, however the pilot gas can continue to flow even if the flame is not present. In most drafty homes of the late 19th and early 20th century, that pilot gas would dissipate in short order. As homes were tightened up in the mid 20th century, that unburned pilot gas could collect and when someone lit a match to try to light the pilot, they often lost their eye brows in a small Puff of gas. Then the Combination valve was introduced and the valve you have was not used by new equipment manufactures.

Eventually most of the appliances like yours were replaced and the parts were for those repairs became less and less in demand and eventually only available by special order.

EdTheHeaterMan

If I found myself at a job like the one you have, The first step is to recommend new equipment, If there is not enough $$$ for that then perhaps there is a government program that can pay for the new equipment for low income homeowners.

If that is not available, then I might upgrade to the newer Combination valve like Honeywell-V800A1088-Standing-Pilot-Valve. That is more like the valve in figure 8 above. That removes the need for a separate regulator and pilot control. You can then disconnect and cap off the manual pilot tubing. You can then redirect the Pilot burner tube to the new valve that is equipped with the regulator and redundant valve, and thus stop the flow of pilot gas.

https://www.amazon.com/Honeywell-V800A1088-Standing-Pilot-Valve/dp/B00ET2JFX8