Large boiler providing heat in 90 year old 4 unit large house conversion.
Looking at a 4 unit investment property that heats on a very old large boiler. Any idea what it would cost to replace an old boiler system, and what is the best options, or is repairing it to keep it going the only option if it breaks?

Should I pass on the investment?
[{"id": "hueb0v5", "text": "That is very common in converted mansion properties.  I\u2019ve seen 1890\u2019s vintage deals that still have and run perfectly fine on the original boiler.\n\nOlder boilers aren\u2019t energy efficient but are much more resilient.  If you\u2019re not comfortable with irregular HVAC, you\u2019re not comfortable with conversions.  You\u2019re alternative is spending $50k+ on a new boiler + any potential excavation costs, or throwing individual units in each unit.\n\nGet it inspected by an HVAC tech and act accordingly.", "replies": [], "depth": 1}, {"id": "huecxrk", "text": "Factor in costs of phasing out boiler and installing forced air per unit. Get a rough ballpark estimate from an HVAC company. If each unit has its own gas meter you can pipe into each new furnace. Gas prices soared this year so you would reduce your operating costs/ utility bills and immediately add some long term value along with getting rid of the dinosaur boiler.", "replies": [], "depth": 1}, {"id": "huf0im1", "text": "Is it a steam boiler or hot water? Sometimes these old steam boiler systems still work incredibly well even after 100yrs. Make sure to have a boiler guy look at it not some random hvac company. (look for the oldest company in your area). \n\nTo convert to individual forced air furnaces you\u2019d be looking at removing all the radiators, then locating furnaces, if they go in-unit you lose floor space and they have to be enclosed in their own room. You\u2019ve got to run gas pipe to each furnace, find where to run intake/exhaust pvc, condensate drain line, and then then all the ductwork through the unit. \n\nPersonally I don\u2019t love individual furnaces and the dry heat they give. And you\u2019re adding combustion appliances and associated risk to the unit, and you won\u2019t have regular eyes on them. Depending on layout and window locations, maybe you can sidewall vent and maybe you have to run the exhaust stacks up thru the roof. Unless you\u2019re looking to rehab, switching probAbly is too involved. That said, you benefit by moving the gas bill to the tenant side. That\u2019ll effect rent you can pull depending on location, but generally tenants undervalue utilities and tend to fixate on listed rent price as opposed to their all in cost.", "replies": [{"id": "hufddzt", "text": "Old steam boiler/radiator system. Thanks", "replies": [], "depth": 2}], "depth": 1}]