A key factor when shopping for a new boiler is the efficiency (AFUE) rating. This rating shows how effective the unit is in converting fuel into heating energy. Picking the boiler with the highest-efficiency rating may seem like a no-brainer, however, these units require different operating conditions to reach their efficiency ratings.
New Cast Iron boilers can achieve 85% AFUE ratings, running system water at temperatures of 160 to 180 degrees. These are the temps used for Cast iron Radiator systems, Baseboard systems, Wall hung systems or any combination of these.
Condensing boilers can achieve 90 to 95% AFUE ratings, running system water at temperatures of 110 to 120 degrees. As you increase the temperature to the system you decease the Efficiency of the boiler. These temps are ideal for In Floor Radiant Heat.
Wondering if it's time to replace your old boiler? If it looks like the one in the picture, you bet. Some things to think about would be, asbestos issues. Your old boiler will most likely have asbestos around it and also wrapping the pipes. An Asbestos Abatement company will need to come in and do the removal. Do you have plans, now or in the future to turn this space into a living area? This would be the time to take a look and see if low hanging pipes could be eliminated, also if your old boiler is oil fed you may think about going to natural gas if it's available in your area.
If your boiler is a newer model say in the last 20 to 40 yrs, we can do a Combustion Analysis on it and give you numbers to help make your decision.