I ran across this site and thread while searching for some info on circulator pumps and repairs. I am a trustee at a church and do some repairs when I feel that I have enough information, experience, and tools. There are two questions I have regarding the same pump set up. Unfortunately, I don't have all of the information so far as the pump capacity, or motor size at hand but can update it if it's needed. The first question is something that I just want to double check before proceeding. I did a re-build on the pump seal/bearing setup. This is one of those commercial set ups with the motor mounted to a flange in which the bearing/seal unit is in, and then has an impeller on the end of the shaft. It's an 8 hole mounting to the pump housing. The problem: I did a "boo boo" and snapped a bolt off when trying to clean out the rusted threads on the housing. (The motor is on a small slab that's raised about 8" off the ground, and the bottom hole is just at the right position to not allow getting a tap into the hole for the job. The setup is with a paper gasket and I was wondering if it's possible to just reassemble it with only 7 bolts holding it in place and not worry about problems, or should I do it "the right way" which involves un-bolting the pipe flanges on both intake and output and the pipes and housing, etc., to get access to the one bad hole to get the rest of the bolt out. (If a tap wouldn't go in, I can't very well get a drill, or bolt extractor in there to get it out where it is.) (The machined side of the pump housing is about 3/8" give or take from the slab.)
The second question involves some information that may help solve the problem of inadequate heating in parts of the building. This is a building that was built in the early to mid 60's so there was no concern with energy conservation. Our biggest problem is not easily solved as there are a large number of single pane windows in the church so we're losing a lot of heat that way. From what I can get from some of the older folks in the church, while it took a long time to get things warmed up, they don't remember having so many problems with it not getting warm enough inside. This of course seems to have changed when they replaced the old single unit furnace with a 3 stage 3 boiler system which brings me to my question. I'm wondering if part of the problem may be that the new circ pumps are adapted to the original piping. The old pipes are 2 1/2" pipes, the inlet to the pump is 1 1/2" and the ouput is 1" going to a reducer to the larger pipe. I"m guessing that the old pipes are part of a convection circulation system, but am not sure. I'm wondering if that 1" outlet on the pump is restricting enough flow that it's affecting the ability of the system to heat the building. The length of restriction is only 2 - 3" if that.