Ok, I am looking for some professional advice. I am replacing an original 1955 radiant heat system with the piping in concrete slab. Last year during a bathroom remodel, I encountered at least one tube corroded thru and thru. I have received several estimates for removing old boiler from my kitchen and installing a new forced hot air system and Central A/C.
Of the three contractors, only one of them took measurements of each room, noted windows, doors, etc. The other two just explained that it was a standard ranch and sized their estimates that way. My dilema is the firm that did took the measurements speced a 66,000 BTU and a 2.5 ton AC unit. The other two speced a 100,000 BTU unit and a 3 ton AC unit. From your experiences, should I trust the guy that took the time to do the heat load calc or should I question why he is so undersized compared to the other guys. All three were using 80% Eff furnaces but the smaller unit was to be a variable speed/two stage furnace. And all three were proposing 14 SEER AC units.
For reference, the house is a one story ranch, no basement, unit to be mounted in the attic with two returns, one at ceiling height and another at floor level.
Also, what is the general consensous on a) Air Cleaner and b)Humidifier....are they truly needed and can they be added easliy at a later date.
Thanks in advance for your recommendations.