Got this stove with external NRV at local sale. It is my first tri-feet stove. It should be made 100 years ago. looks beautiful! Here is the photo when I got it from seller: Later I did dilute vinegar clean, high grade sand paper wet polish, redo the sealing with Viton rubber, and made a leather pump cup from old leather belt. Last week got the shipment of jet removal tool from England. Now with a cleaned jet, it back to live: Now is time for some flame shot in the dark:
Beautiful stove and restoration. You can't beat the engraving on these old Sievert stoves, right? Absolutely beautiful and you've got the old girl running like a teenager sexy external NRV and all. Just the right amount of cleaning. Perfect. Ben
Very glad your guys like this old lady Just add some photo for the external NRV, I like it better over an internal NRV
I am not familiar with external NVR's. Can some one just go through how they work? Perhaps obvious to everyone but me, but I can't see how the air goes through. alan
@salan3 This diagram will help understand how the Svea external NRV worked: The air from the pump makes entry into the tiny chamber under the domed external cover via the capillary tube shown above, with access controlled by the NRV pip & spring. The housing through which the end of the capillary protrudes to reach the NRV has 4 machined grooves which then allow the air which has passed through the NRV to get into the tank by passing back down the outside of the capillary: (some other manufacturers used different systems)
Welcome to CCS, Jesper Hu. Great restoration and presentation. I, too, appreciate the external NRV lesson. What were the disadvantages that led to the abandonment of that feature? I wonder especially in light of the countless threads over the years here about the challenges of servicing 'interior' NRVs.
@Ed Winskill Could it be simply that the internal NVR could be assembled as a unit on the tube then soldered into place. So making it cheaper? Dunno.
The short answer I believe, Ed, is production costs. I'm more and more convinced that virtually non of the changes made since 1894 have added anything worthwhile to the actual operation or efficiency of paraffin pressure stoves. But what they did do was facilitate mass production and cut production costs, even, as you yourself hint, at the expense of operator convenience! Ian
@igh371 Interesting comment which I agree with. We have talked about who has the earliest stove many times, but does anyone know what the earliest stove (of any make) actually is? (Pressurised kero lets say). what has changed in the time from then until now/when these types of stove were at there peak?
Ian, makes sense. I'm not much of a fettler myself, I reluctantly confess, but do have a couple of those old Svea domestics that I bought early on, and have always wondered about that point....
Ian, Completely agree with you, it is a business, so profit drive everything. Even can feel the material used in old time and today are different
