BT7 Heater core box is mounted but the hose from water pump side is not connected. The hose from the block valve is connected and closed. Have never tried the heater core to be sure it will hold pressure. Is there a way to check it by putting water to the copper tube and checking the core inside to see if it leaks? Any ideas how to attach a water hose supply without TOO much pressure? Afraid the house water faucet has way too much pressure.