This solar hot water system was one of the first in Humboldt County. This system is over 30 years old and part of Arcata's pilot program for renewable energy systems. It had a slow leak from both of the dribble valves which are necessary for an open looped system. The advantage of an open looped system is added efficiency from not having a heat exchanger. The old valves were replaced after draining the collectors into a bucket from the drain outlet shown in the next picture. After being drained we replaced the dribble valves with minimum leakage and the problem was resolved.