Why won't Bobcat hydraulic hammer dump hose pressure?

Two issues are seen with trapped pressure resulting from exposure to sun and auxiliary circuit . First : Exposure to sun - heat builds up pressure in all hammers and must be released to connect properly. Connect return hose to skid steer first to allow trapped pressure to vent to drain line, assuming quick disconnects are functional. Secondly: The auxiliary circuit - hammer frequency on small hammers can be as high as 2ooo bpm, with oil flow stopped (spool moves), the response time leaves trapped pressure in return line. The return line must be vented to tank or leakage built into circuit design to account for trapped pressure, making an effective case drain. Results -easy connection. Operator when stopping machine can take a few seconds and drain the circuit by following correct pressure release processes by any skid steer mfg.