Review Boiler Replacement Parts List

[Reicherb]

I’m going to replace a 1966 Weil-McLain PD7 boiler. The boiler is 80% efficient (150,000 in, 120,000 out).


I have the following zones:

Zone 1:

Semi finished basement

836 square feet



Zone 2:

1st Floor

836 square feet over basement and 140 square foot on a slab


Zone 3:

2nd Floor

836 square feet


Using this process to determine my need:

https://www.greenbuildingadvisor.com/article/out-with-the-old-in-with-the-new

I got 50,000 BTU based on January on 2018

I got slightly lower in January of 2017


Using the Weil-McLain sizing guide I come up with 55,000

https://s3.amazonaws.com/s3.supplyhouse.com/product_files/boiler-replacement-guide-381-357-802.pdf


I’m planning to use the Weil-McLain CGA-3 as I don’t want to go with a high efficiency unit that I won’t as easily be able to troubleshoot.


I plan to purchase the following items:

My questions are:


1. I’ve got 3 wire zone valves and thermostats now. I don’t understand the differences between 2 and 2 wire systems. Does it matter which I use?

2. Do I need balancing valves? I don’t have them now. They are expensive. I chose one with a gauge as I don’t know how to set it otherwise. Is that necessary.

3. The installation manual says I need a lined chimney. Is the clay liner in my brick chimney enough?

4. What am I missing from the list above?