The hot water valve is open and the water comes out but it stays cold. We shut off the cold water valve and it made no difference (besides obviously when you turn to cold side no water pours). We turned closed and opened hot valve and it did not change the temp, it when closed had no water came out. The water in the bathrooms gets hot and very quickly. We just got new countertops so everything was disconnected yesterday.
It depends on how you get hot water. There may be a "tankless" water heater under the sink, or very close to it, that was turned off during countertop installation. This is likely, because the sink is getting water, but it does not get hot. If that's the case, just find the instructions for turning it on, and check circuit-breakers as well.
These heaters are popular where energy is costly, since they run only on demand.