In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
I was asked to look at a couple of closed loop solar hot water systems. They want to make sure te system is running properly and if anything should be done to be sure the system will continue to run properly. I am not sure yet what panels or what glycol was used in the systems (haven't been there yet). When I was talking to the customer they said the systems were installed about 6 years ago and nobody has done any work on them since the system was installed. I usually test the glycol with the strips to check its alkalinity and %.
Since the system is this old do you think the glycol should be replaced even if the tests on the glycol show that it is usable?