steam heat vs heat pump, and more...

stephen123123

I have a story 1600 sq ft house that has one-pipe gas-steam heating. The boiler is a Sears/Kenmore model 229-962362. Input BTU/hr: 211,000; Output BTU: 168,800 BTU/hr. Possibly the serial number indicates that it was installed in 1962, about 30 years before I bought the house (which was built in 1930). The insulation in the walls has no doubt deteriorated. The first floor is brick. The second floor was stucco, but later got aluminum siding. To complete the picture, I am now converting the now unheated 28'x12' attic to living space. The attic will be well insulated.
In the 31 years that I've been living there, I have not had the boiler thoroughly serviced. I do drain water regularly, but it still shows rusty in the sight glass. The pressuretrol was replaced last year and properly adjusted. Everything seems to be working though my gas bills in Westchester County, NY, seem high, about $4,000 per year ($875 in the coldest month).
I am wondering if I should have my boiler serviced in some way, or should I replace it. Some say that newer boilers are more efficient, others say that even old ones can be 80%.
Perhaps my boiler was oversized originally? Or, maybe it would be efficient to replace it with two 50,000 BTU/hr boilers, if I can easily separate the pipes going to the first and second floor, so that I could lower the thermostat downstairs during the night.
For the attic, I am wondering if I should extend a steam pipe from a lower floor to the attic for heating. Then, there's the issue of cooling the attic and the rest of the house (now, I've been using 4 window a/c units that I install and remove each year). I could just install them "thru the wall".
For the attic, I am considering installing a PTAC a/c and heat-pump unit, like you find in hotel rooms. They go in a sleeve and cost about $1,000 without installation.
Here comes the big bomb: One contractor recommended two multi-zone mini-split systems with heat pumps. They claim this will replace my steam heating (at a lower operating cost) at a cost of about $30,000 for the entire house (heat and cool) using 7 indoor units (one per room) and two compressors. Although the indoor units are a bit unsightly, is it likely that the operating cost for heating will be less than with my current steam system?
I guess, alternatively, I could install mini-split systems that are cooling only. Which makes more sense?
I am not sure if a conversion to forced air makes sense. It's better in appearance, but quite costly and challenging with the ductwork needs.
I do think the next step for me is to get an energy audit, as sealing leaks, etc, could yield a big savings, but any help in answering the above questions would be appreciated.

Steamhead

@stephen123123 , first thing you need to do is remove pricing information from your post. This is prohibited and has been for a very long time- go here:

https://heatinghelp.com/forum-user-manual

Next- you do NOT want to ditch the steam system. No forced-air system will ever equal its comfort and efficiency- and heat pumps are the worst of all.

If one of your second-floor radiator risers has enough capacity, it should be a simple matter to extend it to the third floor.

pecmsg

Nothing wrong with a heat pump for 65 - 75% of your heating needs. Now when that Northeast winds start to blow, the mercury drops and the snows falling it will have problems keeping you comfortable. Thats when you're going to miss the steam. Besides where are you putting the winter gloves and snow suites to warm them with a heat pump?

Hot_water_fan

If you go heat pump, the multi-split is the worst option by far. Find a way to get at least some ductwork in the house. Maybe two ducted systems, one for each floor? Oil is expensive right now but none of us know future energy prices. I use a heat pump for 100% of my heating, I don’t notice a comfort difference between it and radiators but YMMV.

WMno57

Hot_water_fan said:

Oil is expensive right now

Oil WAS expensive this summer and fall. Today it is $2.85 a gallon. Lowest it has been in 10 1/2 months.

stephen123123

If I did extend a steam pipe to heat the attic, then I still need to provide a/c there. Do I just put a thru-the-wall a/c unit? Would that solution be better than a combined cool-heatpump-heat unit (like they have in hotels or a thru-the-wall cool-heatpump-heat unit)?