Weil McLain HE-5 Series 3

GroundUp

I recently purchased an investment property with 6 apartments, using an old HE-5 boiler to heat 6 zones of baseboard. It's grossly oversized at 133k input (only 104 ft of element in total) and eventually I'd like to replace it, but I'm having a hard time taking the old gal out after so many years of loyal service. I can't read the serial number on the tag, but I can see series 3. The building was built in 1982 and the previous owner told me he thought the boiler was original to the building. Does anybody know the time frame when these were made? This place is 150 miles away in northern MN so I can't just run up there to swap the boiler if it fails on a -40* night so I'm trying to be proactive, but a new one (thinking a CGi-4) may just as well fall victim to failure on a subzero night. I don't know a lot about these CI units so I'm not sure if it's ready to go soon or if it's got some life left in it. If it's already on borrowed time, I'll just swap it out before next winter but if it's not, I'll take my chances and wait. What are the common failures with these units?

kcopp

Thats the right timeframe.
The fan and the boiler control could be failures.
That being said an inspection of the boiler from below may give you some clues to a leak. Hard to say for sure but they are pretty decent units.

GroundUp

kcopp said:

Thats the right timeframe.
The fan and the boiler control could be failures.
That being said an inspection of the boiler from below may give you some clues to a leak. Hard to say for sure but they are pretty decent units.

Thank you. I did open it up and it looks great inside, no signs of leakage between the sections or anything and the makeup water is off. Fan is quiet and I do have a spare that came with the property. The maintenance guy who takes care of the property was a boiler operator at the local hospital in a past life and takes good care of this system, but I'm sure there is only so much that can be done. 39 years seems to be stretching the limits from what I've been reading?

kcopp

You are getting there but hey if it isnt broke dont fix it.
I would have a plan in place in the case it goes south fast.

The Steam Whisperer

If you have space, and do a little repiping, I would install a second unit and leave the old one tied into the system as a back up. If piped properly with primary/secondary piping and/or with check valves, the off unit will stay cold while the other unit is running, so you maintain full efficiency of each unit. You could also install a unit with just enough capacity for your typical winter day weather so you max out it's efficiency, and then bring the larger unit online during the few days of extreme weather a year.

GroundUp

The Steam Whisperer said:

If you have space, and do a little repiping, I would install a second unit and leave the old one tied into the system as a back up. If piped properly with primary/secondary piping and/or with check valves, the off unit will stay cold while the other unit is running, so you maintain full efficiency of each unit. You could also install a unit with just enough capacity for your typical winter day weather so you max out it's efficiency, and then bring the larger unit online during the few days of extreme weather a year.

Good thinking! I was considering the idea of putting an electric boiler in series for the same reason, as the dual-fuel rate at this property is only $.058/kWh. I've done a few systems like this, recently one in another apartment building, and they are working out great. There is only 100A service currently to the mechanical room so I'm waiting for a sparky to get back to me on the cost of bringing 200A in from the pole. I hadn't considered adding in another gas boiler like you suggest- maybe even a mod/con at that, to maximize efficiency on warmer days. Now you got my wheels turning!

The Steam Whisperer

GroundUp said:

The Steam Whisperer said:

If you have space, and do a little repiping, I would install a second unit and leave the old one tied into the system as a back up. If piped properly with primary/secondary piping and/or with check valves, the off unit will stay cold while the other unit is running, so you maintain full efficiency of each unit. You could also install a unit with just enough capacity for your typical winter day weather so you max out it's efficiency, and then bring the larger unit online during the few days of extreme weather a year.

Good thinking! I was considering the idea of putting an electric boiler in series for the same reason, as the dual-fuel rate at this property is only $.058/kWh. I've done a few systems like this, recently one in another apartment building, and they are working out great. There is only 100A service currently to the mechanical room so I'm waiting for a sparky to get back to me on the cost of bringing 200A in from the pole. I hadn't considered adding in another gas boiler like you suggest- maybe even a mod/con at that, to maximize efficiency on warmer days. Now you got my wheels turning!

If you baseload with a smaller boiler, a modcon is probably not worth the cost and trouble. You've already probably picked up most of the efficiency gain with a small baseload boiler since it will be running at peak efficiency. Most large single boilers that we replace with simple stage fired atmospherics cut fuel usage about 30% and as high as 70%. Of course the existing boilers are usually oversized.