After restoring my Prentiss Wabers No 8, I had my eye open for something similar. I found a Preway, same company, in the 4521A model. It looks like it has seen light use. It required very little from me. I washed it a bit and pressure tested it. No leaks showed up but the NRV in the pump allowed the pump shaft to stand proud. On this model there is a pip that is accessed from the outside of the removable pump. The spring seemed very weak so when I dug out an Optimus pip I tried another spring. The pip fit perfectly but the spring was too strong. So I slightly stretched the original spring and it seemed to solve the issue. I really like this little double burner. It seems to be from the 1940's according to more knowledgeable people.
I like the burners on these, and find it easy and intuitive to achieve a simmer with the lever-action valve on the right hand burner. ....Arch
That's about right. The 1945 models were made for a few years until the 4821's, 4822's and 4823's came out in 1948. I don't know what the suffix letters (P and A) stood for. Slight differences in the pumps and filler caps, I'm thinking, as there are several variations of these. I just wish Prentiss-Wabers would have used actual check valves instead of NRV's. I really like the flame pattern through those steel burner plates.
I have a Prentiss Wabers embossed P4522 and a Preway 502 p with the stove body decal and they both have pumps on opposite ends from the filler cap.
