In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Want to move from oil to gas boiler. Best way forward?
I live in Lancaster, PA. We have an old, inefficient oil boiler. For a number of reasons, we would like to replace the boiler with a high efficiency gas combination (combi) tankless boiler / heater. I was / am interested in Navien, and was settled on the NCB-240. Its specs seem excessive for our ~2-story, 1200 sq ft (7 hot water radiators on a single zone), 1 bath home, but I thought better to oversize. My assumption is that an oversized unit doesn't affect operating efficiency, or certainly not to the degree that an oversized wood-burning appliance does...
Anyway, I contacted our gas utility to inquire about gas pressure. The response said, 'your home is located on a street that has LOW PRESSURE MAIN - you will need to purchase standard equipment with a minimum input rating of 3.5" of water column. If he (my contractor) can provide you with 2" water column that would be best.'
I'm not the sharpest tool in the shed, but I think my utility rep meant that I should purchase equipment with a maximum input rating of 3.5" w.c. and preferably a boiler that doesn't require more than 2" w.c.?! At first I thought great, the Navien NCB-240 would work. After all, the NCB-240 brochure (http://www.navienamerica.com/__DATA/ProductDocument/2013/11/12/13-1108%20NCB%20brochure%20Flip%20book.pdf) on page 3 states, "Our negative pressure gas valve ensures maximum performance all the way down to a minimum gas pressure of 3.5" of water column." I passed this information on to my contractor. He responded saying that the pressure supplied by the gas main would be insufficient for the boiler. I'm a bit frustrated because a) my contractor isn't being very responsive with suggesting alternative systems and b) just today I got a flyer from my gas utility, urging me to switch to natural gas heat and save up to $1500/yr. The only currently installed gas appliance is a gas range/oven.
Does my utility and/or contractor know of what they speak? Any chance the NCB-240 (or a competitive unit) would work for me? Any other ideas / suggestions?