Oil to Gas... Hey Pros is this a Crazy Idea?

Joseph_4

I am a heating contractor. This year oil prices have gotton so out of hand that I decided to switch myself to Gas. Right now I still have my  oil boiler and tank being used for domestic hot water as it has a tankless coil, as well as right size gas lines in my boiler room. Have done lots of research about price comparisons with my gas utility company. It seems Gas was the equivelent of about $3.50 a gallon a few years ago and no one knows what the future will bring. (i understand gas is in therms not gallons.) so here is the idea. leave my oil boiler for use the whole year for domestic hot water only. Install a new gas boiler and pipe it into my forced hot water heating system with a bypass to my current oil heat system set up and in years when gas is more expensive than oil. will close the intake to my gas system. obviously will need  a bunch of ball valves to direct the flow properly with an expansion tank and prv for each boiler. and possibly separate  taco pump for each system and maybe each with separate thermostat. what do you think?

Thanks

Joe 

Steamhead

What make and model oil boiler

do you have now? 

Joseph_4

have a peerless jot 175w

  I have a peerless jot 175w with a riello burner burning a 1.10 nozzle, pump pressure is set at 145. on my chart it says thats a firing rate of a 1.25 nozzle

Greg Maxwell

Conversion

I am assuming by your mention of a gas utility that you are going with natural. Please look at the system whenever converting from one fuel to another. Your advertised AFUE on this new gas equiptment is in my opinion misleading. Your system needs to meet the conditions that they rated the boiler at to get those advertised conditions, which usually is a very low return water temp to get the unit to condense. It is very seldom that on a baseboard boiler conversion job you will meet those conditions, resulting in a much lower efficiency, and much higher fuel bills than you anticipated. The standard 180 supply, and 160 return arent going to cut it.

Steamhead

Then it's considerably oversized

I'd replace it with a three-pass unit, properly sized. Biasi, Buderus, Solaia and others are three-pass boilers that can burn either oil or gas. With one of these you don't need to run two boilers- juist change the burner and the necessary infrastructure (tank, gas line etc) if you want to switch fuels.



Whichever fuel you use, you'll save by not having an oversized boiler.

Greg Maxwell

Boiler Swap

I agree 100%.

Robert O'Brien

Get a real gas boiler

Do a heat loss and keep in mind the all the software has a 30% or so fudge factor in it, you'll find the Peerless is 3,4 or 5 times oversized. The baseboard/condensing boiler mismatch theory is nonsense,BNL did a study on this topic you can read about here

http://www.bnl.gov/isd/documents/28709.pdf



Every house is over radiated and design days are far and few between!

Joseph_4

Its not oversized...did the heatloss

did the heatloss  before i started the thread, and including the baseboard in basement. comes to 118,427 btu add in a 15% pick up factor and I get 136k. on Peerless chart the boiler close to what i need in cast iron would be MI-06  which is 175k input. (personally am not interested in mod-con boiler as per Greg's point,i don't have radiant heat etc..)

Robert O'Brien

Baseboard in basement?

How is that germane to a heat loss calculation?I've seen very few 136K houses and they were either real old,tons of glass or just immense!

Steamhead

Bob is right

there is almost always more baseboard than the house needs. So you need to determine how much heat the house actually loses, and size your boiler to that. If you're not sure how, have a pro do it. The results will almost certainly surprise you.



The MI series is an atmospheric boiler, which loses a lot more heat out the base and up the flue than a 3-pass. I wouldn't go with it.