Replies

1. 
   J Chesnut | Dec 20, 2010 09:37am | #1

   John,
   If you have a high efficiency modulating boiler I would recommend an indirect hot water tank. An indirect is heated by the boiler and not having a combustion unit itself it can be insulated to a much higher degree.

2. GBA Editor
   Martin Holladay | Dec 20, 2010 09:48am | #2

   John,
   Plenty of manufacturers make direct-vent sealed combustion gas water heaters:

   http://www.amazon.com/Bradford-White-DS150S6FBN-337-Gallon-Natural/dp/B003A69L8I

   http://www.rheem.com/product.aspx?id=EE3D5D0D-0FDF-4EF1-B8BD-378FBFA903CC

   http://www.statewaterheaters.com/prod/residential/res_gas_pdv.html

3. 
   toymaker | Dec 20, 2010 10:19am | #3

   Thanks guys. Looks like I need a new water heater guy.

4. 
   J Chesnut | Dec 20, 2010 11:09am | #4

   John,
   HVAC contractors are usually tied to certain brands of appliances. Sometimes it takes researching finding what appliance specifications you want and finding a contractor that uses these products.

5. 
   steve bumpus | Dec 20, 2010 06:03pm | #5

   John:
   I just got done investigating them myself, and you got two choices: powered direct vent that require 110v. and about $500 more over the basic direct vent. the direct vent uses combustion air from outside via double vent pipe. ( better for tighter homes, but the power direct vent will require combustion air from inside air already heated, so in my case, just a direct vent water heater is more appealing and economical in a couple ways!!

6. 
   Tony Olaivar | Dec 20, 2010 08:48pm | #6

   Most high efficiency WH units are capable of using outside sources of combustion air. This is a step that gets skipped for the convenience of the technician. Not a good sign that he/she has your best interests at heart. Find another dealer. Tony Olaivar - HERS Rater, BPI Professional - Lanz Heating and Cooling