Want to replace Solar Hot Water Heater

[ardcarmvk]

I am looking to replace my solar hot water heater only. I have asked several companies for estimates but they all seem to want to sell me the whole system. Little bit nervous not sure where to buy as my home stores don't seem to have decent pricing or knowledge. I have replaced a conventional water heater before but not sure what steps to take for solar. Thank you very much in advance for any help that can be given.

I live in Sunny Arizona this is what I have now.
17 year old 82 Gallon State Solar/electric water heater w/ Goldline differential. Don't think I need such a large tank since I am only one person and don't use much hot water. I am open to just getting a conventional water heater w/ timer but would like to replace solar heater if I would get ROI in a decent time.

I guess questions that I have are what would you do conventional 40 electric w/ timer or replace solar unit?
Where can I find out more on how to replace solar unit.
Local stores only have one solar model its pretty expensive what are my options. Don't think I want to sped more than $800.
If I detach glycol lines on top will it dump all over? Where do I get replacement glycol?
Do I need to replace differential? If not how do I make sure its set up correctly. It has been messed with in the past.

I have pictures of what I have here:

 

[johnjh2o]

You can't get a standard 80 electric water heater for much less the $600.00. As far as a solar heater they are all 80 gallon. If I were you I would forget the solar heater and install a 40 gallon electric heater. Being your the only person that will be using the hot water your pay back for solar is way out there. As far as a timer with today's tanks they are insulated so well that chances are with no use the water in the tank would stay hot enough for the day that it would not come on.
John

 

[ardcarmvk]

Thanks John for your reply. I made a x-post on another forum and was given a great idea for modifying my new conventional WH with my external heat exchanger. Included is an article from home power magazine on One-Tank SDHW Storage with Electric Backup.

http://www.solarpaneltalk.com/showthread.php?7267-Looking-to-replace-solar-water-heater&

 

[johnjh2o]

Not sure if you get freezing temperatures were you are but the system in your link is a direct solar setup. You mentioned using glycol. That tells me that you do get freezing temperatures. If you do then the direct system won't work. It will freeze up. During your colder months.

John