Sink Sprayer help

[jpj46]

I just moved into my first house and found the sink sprayer with extremely low flow, basically not working. I pulled out the sink and found a complex mixing valve with the sprayer attached. It's a bridge sink so the water runs to each handle, then down to the valve, where the sprayer is attached, then back to each handle and is mixed again in the bridge sink before coming out of the faucet. What I can't figure out is why there is low pressure coming out of the sprayer. I took everything apart and it seems to be working properly. There is pressure coming into the four way valve that the sprayer is attached to, so it seems like I should have pressure but I don't. The pictures below show the valve, water comes into the larger fixture which has a valve between that opens when under pressure and flows into the smaller fixture before flowing back to the faucet. The sprayer is attached to the right of the larger fixture so it is before the valve. Was this system just poorly designed from the beginning? How should I approach troubleshooting this issue?

 

[jpj46]

Huh, no responses, I guess here is a question to make this more interesting: do mixing valves below sinks need a back flow valve in them? I believe the valve is causing the issue. Is there a way to temporarily disable a valve?

 

[Twowaxhack]

Post a picture of the faucet.

 

[jpj46]

Here is a picture of the faucet

 

[Twowaxhack]

That’s a Kingston Brass faucet.

The Model is English Country.

Here’s a link to it. You’ll need to call Kingston Brass tech support and order a new diverter for it.

https://www.kingstonbrass.com/produ..._content=sag_organic&utm_campaign=sag_organic

 

[jpj46]

Thanks so much for the help!

 

[BlueSkyHigh]

@Twowashack is a veritable Encyclopaedia Britannica of plumbing knowledge!