Has anyone ever seen a shower that has no hot or cold control?

My friends shower has no control over the mix of hot and cold water, only control over the pressure and the water is coming out is not super cold, but cold enough to make it a torture to take a shower. Was trying to help her fix it as the landlord has been unresponsive in fixing it. In looking under the house I can see hot and cold pipes going to the shower but no way to adjust the temperature.Has anyone ever seen a shower that has no hot or cold control?
there is a thermal control next to the water heater its normally used at public locations not residential turn it up .





if there is not ont there turn the water heater upHas anyone ever seen a shower that has no hot or cold control?
Are you sure turning the lever only increases flow? Sounds a bit strange to have no temp control. If there is hot water at the sink in the same room, I'd try seeing if turning then lever more changes the temp. If not, my guess is that the control is malfunctioning. To get a kit to repair it, you need to know the make. I'm assuming it is a single lever shower like Delta or Moen. Good luck. By the way, I'd shy away from cranking up the water heater setting above the normal setting, since that may expose you to scalding at some other faucet.
It may be a scald prevention control, usually one can still adjust it, but perhaps it is out of adjustment. If it is a scald protection faucet, there should be a plastic cap on the handle, use a small screwdriver to pry off cap and there will be an adjustment inside. If this is the case you may need to adjust it again in summer.