I converted from oil to natural gas this year. Here's the process:

1. Contact RI Energy and tell them you'd like to convert to natural gas and need a list of recommended installers.

2. Contact at least two of the recommended installers and get written estimates. We had Petro and Gas Doctor come down; chose to go with Petro

3. Fill out one sheet of paperwork with your installer that goes to RI Energy that outlines the size of your new boiler, where the proposed location of the meter goes, and what the cost is.

4. Wait for approval.

5. When approved, RI Energy will run the line to your house for no charge since you're going to be their customer (assuming your street has a gas main). You don't have to be home when they put in the line. They do this April to Sept. because of the ground freezing up in the winter. We had to wait and nurse a leaky boiler and tank through last winter because of this.

6. Once the line is in, work with your installer as to when the full install will be done. Your installer will coordinate with one company to remove your old boiler, another company to remove your tank, and a plumber who will hook everything up. This could take two days.

7. When everything is ready to go (typically the second day), a building inspector will come down to check out the work, then RI Energy will install the meter, then you're ready to go!

I'm really happy we finally switched. Total cost was around $10k before rebates. Since we no longer had a tankless water heater, we also had an indirect water heater installed. I paid cash ($2300) for the boiler to get a $715 rebate, then financed the rest in a 0% interest 18-mo loan.

Hope this helps!