Do not forget the need for a flue with a propane heater.

Anyone else?

What size is your current electric water heater and has it been doing a satisfactory job?

If you Google around you'll find more info on tankless heaters than you can read.

For starters they are expensive. Second, they require higher volume gas lines than a conventional tank style water heater and unique vents which are costly. Third, tankless water heaters do not work and play well if you have hard water.

Those are all important preliminary considerations.

Current size is 80 gallon. We do have hard water but have a water softener.

If your softener is correctly sized and set up properly for efficient operation then you've got that covered.

Again, has you current water heater been doing a satisfactory job?

Yes but expensive electric bills and after 3rd shower of morning not much hot water.

Then it hasn't been doing a satisfactory job, has it?

I can tell you that around here it costs less to heat water with LP than electricity and the LP heaters seem to recover a little quicker.

If you get a concise estimate for a tankless including the necessary vent and gas line you might be shocked and that may make up your mind for you.

With 7 people in your home you might look into two LP tank heaters in parallel.

It's VERY rare to see a softener that is correctly sized and set up for 7 people so you should get some water hardness test strips and check if your softener is actually providing you with 0 hardness water cause that may be why you are replacing your current electric water heater.

Have you considered switching to low water use faucets? That might cut down on water use, amount of hot water that needs to be replaced and electric bills all in one. I put in some new low water grohe shower heads and control valves and can't really tell the difference in water volume but I can see the difference in my water and heating bills.

In our area, propane is over $3 per gallon in summer and over $4 in winter, making electric heating the clear choice. Every water heater has an energy factor number associated with it. Most electrics are around .90, while most propane units are around .60. You can use these numbers, along with the cost of energy in your area, to compare the relative cost of operation for each type of heater.

For the electric heater, take the energy factor for the water heater that you are considering and multiply by 0.003412. Now take the cost per kilowatt that you are paying for electricity, and divide it by the first number.

For the propane heater, take the energy factor for the water heater that you are considering and multiply by 0.091333. Then take the cost per gallon that you are paying for propane, and divide it by the first number.

The two results that you get are the relative fuel cost per million BTU's for each heater.

Check the DOE's web resources for good water heater information. Where do you live? If it is hot and humid there, a heat pump water heater might make sense. If you are in a warm, sunny environment, and tax advantages are generous, solar might make sense. If you are going to make a choice between propane and resistance electric, check out this worksheet to compare methods.

http://www.energysavers.gov/your_home/water_heating/index.cfm/mytopic=13010

Most people look into a solar hot water heater because they want to save money on their heating bills. With this in mind a solar hot water heater will help to reduce your bills by pre-heating water that goes into your traditional boiler. It is unlikely that the system will be able to heat the water to such an extent that the boiler is not needed so although you will save some money on your bills it is unlikely that you will cut them out altogether. plumbing vancouver