Best Of

I suggest considering installing 2 or 3 smaller boilers to match the load at design conditions.

Be prepared for extra wiring costs for lead/ lag, cascade, outdoor reset, constant circulation, and other control and piping strategies including combustion air requirements.

Hire a shoring / rigging company for boiler removal and getting the new equipment in place.

I've done several change outs this way and the heat loss has always resulted in a lower btu requirement.

In the old days they used to say take the price of the boiler and double it=installed cost.

That never worked IMHO.

I found at one time if you took the cost of all the material including the boiler and doubled it that was in the ballpark.

But that was long ago.

With today's labor and material cost its anybody's guess

Unless the Nest has a W2, second stage kicks in either 7 or 12 minutes into the cycle depending on a Dip switch setting.

To answer your question, if my heat loss was 66K, I wouldn’t install one capable of 88K.

Our ISE GD was installed in 1995. It was the top of the line at the time.

It reverses with each use. We put everything down it except bones, grease and banana peels. The coffee grounds with the filter go down it also.

We make a point to run it twice each use and plenty of water.

I recall it plugging only twice in these 30 years and got it going by multiple reversing.

Never taken the drains apart.

Had a fridge glass shelf shatter with crumbs down the GD. Cleaned out what I could and did not want to drop the GD to empty. I thought, well if it dies, it dies.

I hit the switch and it growled for a few seconds and all was good. That was about 5 years ago and still going strong. The extra money in 95 was well worth it.