I would suggest, having a comprehensive audit done on your home first and then research for sealed combustion boilers supplied in your area.
Look for these attributes:
- sealed combustion
- 95-98% efficient
- one that gives the supply houses the fewest return calls
You must also eliminate the moisture in the basement first.
For more information:
Read "We need to replace our oil-fired boiler. We have estimates for 4 oil-fired boilers but do not know which is best. Is a gas boiler better?" a Q&A answered by Bill Bradbury.