deeMatrix
New Member
Hi,
We are considering finally replacing our Weil-Mclain CGA5 cast iron boiler that I posted on here two years ago that has served us very well for 27 years but has been making boiler knocking/percolating type noises during fire stage. After evaluating a few contractor proposals we have decided we are not comfortable with mod-con units with our micro zones, contractors experience, higher cost, etc. so we are planning to go with a similar type cast iron boiler but add in an indirect water heater as part of the project.
We had a Manuel J performed which indicated around 68000 BTU heat loss. I also did the dry bulb approach last year that Dana outlined in an article a while back using my actual numbers and it arrived at around 62500 BTU/hour @ 60F.
One contractor indicated that the Manuel J heat loss number was on the borderline between a CGA3 (59000 BTU out) and CGA4 (88000 BTU out) but thought it was too close for comfort so wanted to go with the CGA4. The CGA5 is 117000 BTU out which the numbers show is oversized but our existing one has served us quite well for 27 years but some short cycling at times with our micro zones.
One contractor who we like is indicating that he will put in the CGA4 but indicates he would personally stick with a CGA5 with the Aqua Plus 45 indirect water heater as part of the solution. As indicated, we have had great success in our home with our current CGA5 but based on the heat loss/dry bulb numbers it shows the current boiler was way oversized.
Obviously we are a little confused and not sure if we should still tell him to go with the CGA4 or go with what has worked and what he would personally go with, especially in light of the addition of the the new 45 gallon indirect water heater. Thoughts?
Thanks in advance.
deeMatrix
We are considering finally replacing our Weil-Mclain CGA5 cast iron boiler that I posted on here two years ago that has served us very well for 27 years but has been making boiler knocking/percolating type noises during fire stage. After evaluating a few contractor proposals we have decided we are not comfortable with mod-con units with our micro zones, contractors experience, higher cost, etc. so we are planning to go with a similar type cast iron boiler but add in an indirect water heater as part of the project.
We had a Manuel J performed which indicated around 68000 BTU heat loss. I also did the dry bulb approach last year that Dana outlined in an article a while back using my actual numbers and it arrived at around 62500 BTU/hour @ 60F.
One contractor indicated that the Manuel J heat loss number was on the borderline between a CGA3 (59000 BTU out) and CGA4 (88000 BTU out) but thought it was too close for comfort so wanted to go with the CGA4. The CGA5 is 117000 BTU out which the numbers show is oversized but our existing one has served us quite well for 27 years but some short cycling at times with our micro zones.
One contractor who we like is indicating that he will put in the CGA4 but indicates he would personally stick with a CGA5 with the Aqua Plus 45 indirect water heater as part of the solution. As indicated, we have had great success in our home with our current CGA5 but based on the heat loss/dry bulb numbers it shows the current boiler was way oversized.
Obviously we are a little confused and not sure if we should still tell him to go with the CGA4 or go with what has worked and what he would personally go with, especially in light of the addition of the the new 45 gallon indirect water heater. Thoughts?
Thanks in advance.
deeMatrix