Weird. I’ve seen plenty of dual tap systems but never an open water heater. Dual tap are simpler and cheaper - that’s what they used long ago. Where are you that you see this?
I certainly remember a time when most faucets and valves were dual tap gate valves with rubber washers, because the o-rings needed for more complex faucets were expensive or not yet available
They still seem to be used a lot in countries like the UK where I guess they want to feel like steampunk engineers every time they want to get the correct temperature of water come out of their taps.
Gate valves not globe valves? Maybe they are just older than me but gate valves seem like a horrendous design for faucets as they are generally much larger than the size of the piping due to the gate and they have very poor throttling capabilities
Gate valves are a great design because they take advantage of the natural properties of rubber to make a seal. When compressed, rubber washers do well at spreading out to make a good seal. However rubber does not have the integrity to work under constant compression and with sideway movement, as an o-ring in a modern faucet.
Gate valves are a great design, because they’re relatively simple, easy to manufacture, and tolerant to rough manufacturing and irregularities.
Once you’re able to cheaply mass produce synthetic rubbers with varying properties, metal parts with higher precision and greater complexity, the possibilities function much better
Weird. I’ve seen plenty of dual tap systems but never an open water heater. Dual tap are simpler and cheaper - that’s what they used long ago. Where are you that you see this?
I certainly remember a time when most faucets and valves were dual tap gate valves with rubber washers, because the o-rings needed for more complex faucets were expensive or not yet available
They still seem to be used a lot in countries like the UK where I guess they want to feel like steampunk engineers every time they want to get the correct temperature of water come out of their taps.
Gate valves not globe valves? Maybe they are just older than me but gate valves seem like a horrendous design for faucets as they are generally much larger than the size of the piping due to the gate and they have very poor throttling capabilities
Gate valves are a great design because they take advantage of the natural properties of rubber to make a seal. When compressed, rubber washers do well at spreading out to make a good seal. However rubber does not have the integrity to work under constant compression and with sideway movement, as an o-ring in a modern faucet.
Gate valves are a great design, because they’re relatively simple, easy to manufacture, and tolerant to rough manufacturing and irregularities.
Once you’re able to cheaply mass produce synthetic rubbers with varying properties, metal parts with higher precision and greater complexity, the possibilities function much better