Just thought I would share my experiences with my DIY heater install. I did my research before I even thought about ordering it. I downloaded the owners manual for the heater I was thinking about, and read the manual to be sure I could do it all myself before I bought the heater. So here are a few gotcha's to watch out for:
1. Make sure you get the right size heater(BTUH) for your gas line and gas meter if using natural gas. I didn't use propane gas, but I am sure you would have similar limitations. The old heater that the original owner had installed was a 350k BTUH. But the line that he had run to it was about 60 feet long and only 3/4" diameter. It was way under supplied and starving for gas which caused a lot of sooting and the original owner said it only lasted about 2 years. I had to rip out all the 3/4" pipe and install 1 1/4" supply line from the meter, then tap the 1 1/4" line with short 3/4" runs to my appliances and pool heater. Also call your gas company and ask them if your meter can supply enough volume for your heater, in addition to any other natural gas appliances you may have.
2. Check to see if your local laws allow you to do your own work. In my county, Columbia County GA, you are allowed to do anything you want on the customer side of the utilities. But you do have to get a building permit, and have the work inspected when you are finished. Building permit cost me $50 which includes the first inspection. If I don't pass inspection, it costs $30 for each re-inspection until I get it right. I started by calling a local plumber first, BAD IDEA. The local plumber told me that I would be fined $500 if I touched anything in my house, even if I changed out a leaky fawcet. I figured that was bull, so I called the county officials that issue building permits and do inspections. They gave me the real story. In my county, you only have to have a permit if you are doing major structural work, or something like I did with the gas line.
3. Set your heater on something that will prevent it from being flooded if the water lines nearby rupture. I have mine sitting on a cinder block pedestal. The old heater was sitting on the ground level and was completely rusted out in the bottom. Original owner must have just let the backwash hit the ground, and the heater is right beside the filter.
4. Leave plenty of space around the heater so you can work on it. I have about 3 feet on all sides but the back, which has about 6 inches. Made it real nice when I swapped the water inlet and outlet to the left side, cause it was manufactured on the right and my supply was coming from the left.
5. Flexible PVC? I used flexible 1 1/2" "SPA" PVC when running my water lines to the heater. It just made it easier to pull a hose up and glue it instead of using $20 worth of 90 and 45 degree elbows to get my line from the multiport on my filter to the heater. It does cost more, but for me it is worth it to not have the hassle of lining up all the freaking fittings.
6. One thing I didn't do that I learned - buy more pipe and fittings than you think you will need. I made about 5 trips back to lowes, home depot, and Ferguson plumbing supply before I finished the job. Save your receipts and if you don't use an item, you can always return it.
7. Have a Helper. I could have done it all myself, but my teenage sons really made the job 10 times easier. Their backs are still limber and not nearly as stiff as mine. Makes crawling under the house dragging pipe not so formidable a job.
8. Don't forget to bleed the air out of the gas line when you finish. Or it will take forever for your appliances to light.
I will post pictures when I get more time. Just thought I would get this down while I am thinking about it.