We are in southern, coastal Maine.

We have a 1978 split level. Originally built for electric heat, the previous owner installed an oil fired-FHW boiler. The house is generally well-insulated with 6-inch walls and newer windows with a relatively open plan.

The boiler is 20 years old. Generally in good shape, but I know it’s in the latter part of its lifespan.

We are planning on installing mini splits to take advantage of the current tax incentives. My plan is to see how well they work — will they heat the house adequately and efficiently? If so, then the aging boiler goes and we add a heat pump hot water tank.

However, I’m taking a second look at my plan and I’m wondering if I’m being stupid for letting the incentives drive my decision. Should I ditch the mini-split plan and focus my finances on a new, more efficient boiler? The mini-split install will come to about $9K (maybe less with tax incentives) — that would go a long way towards an efficient boiler.