Steam heat problems

[Mike Abramowitz]

Currently own a 3 family in the Boston area which has steam boilers for heat, (3 separate systems) 1 of the systems was no used for about 15 years until last year when we purchased the home. The other 2 were not well maintained it seems. We are now at the point where 2 of the systems are unbearably loud for the first 15 minutes or so turning on. We've had a plumber over to try and get them to quiet them down (didn't work) is it worth dumping more money into these systems or just biting the bullet and putting forced air heat in the house? (which would be significantly more tenant friendly)

[Ann Bellamy]

If you already have 3 systems, you are ahead of the game.  Also, although I don't currently have any steam systems in any of my buildings, I understand they are actually a simple system, so diagnosis of the issue shouldn't be that difficult.

A quick google search yielded lots of results about improving the efficiency, since it's a system that you already have. 

If I were you, I'd pay an HVAC company to come out.  Evidently the plumber you used is not that familiar with steam.  Since replacement of 3 systems is prohibitively expensive, and since with 3 separate systems, your tenants will pay for heat, I think it's worth investing in a service call from an expert.