underground boiler pipes leak every season - need permanent solution

Detroit_66

We own a few units in a 1960s era, two-story, 16-unit cooperative Detroit apartment building. The building is served by an old boiler we had to shut off recently because of the high water bill due to the most recent leak -- 0 pressure in the boiler and it appears to be from 1989 - it's pretty old and has had various components fail, maybe because all the makeup water and stresses and strains as the results of the leaks? We've been playing whack-a-mole with the leaks for the past decade or so, busting up concrete in different 1st floor units to repair the pipe-- the building is on a slab. No basement, no attic to re-route pipes out of the ground. From everything I've read in these forums it sounds like these were the cheaper copper pipes (K-type?) used in the 60s, so they're already 60ish years old and springing leaks. I've read up on pipelining and pipe bursting, both of which sound promising but seem limited to sewer piping, not hot water boiler flow and return pipes. The building is a co-op building meaning it's owned by a co-op association, of which the owners are members. We've had a couple companies come out, but only one has proposed a solution for the pipes involving relocating the pipes out of the ground and in the individual units and hallways, a project that could run upwards of 50k or more, would not be aesthetically pleasing and we'd still need a new boiler. We're trying to stay with boiler because of the much lower cost to heat. I've explored the electrical route with PTAC and it's early but not promising as we've been told we'd have to upgrade the electrical (100k), i.e., service upgrades for each unit and more that I don't have the words to explain just yet, I'm learning. These are low income residents, half or more of retirement age. Any advice would be greatly appreciated. This is my first post. Thanks so much.

Jamie Hall

Well, let's figure out one thing first. Is this hot water, or is it steam? I'm thinking hot water, but before I -- or anyone -- can get much further we really need to know.

Then one more critical detail: is this a flat roof building? And is the roof accessible?

And I presume the individual units are all single story, so eight up and eight down?

Detroit_66

Correct. Hot water, not steam. Flat roof. I think it's accessible but will check.

Detroit_66

And yes, single story, eight up, eight down.

mattmia2

there are some types of commercial baseboard radiator that are in larger cabinets that can be run around the perimeter of the building with room for supply and return mains in them, that might be a retrofit option. nothing is going to be particularly inexpensive, what ever you do you are installing a new distribution system for the heating.

Jamie Hall

Without knowing the full layout of the building, the possibility which strikes me as a first option to look at would be to run a reverse return main distribution system on the roof, in a VERY heavily insulated box. Then run supply and return runs down to each individual unit in some convenient location in each unit to hook up to the existing radiation. Yes, you would lose some heat from the roof mounted piping. But if the insulation is good, that would be a relatively minor loss.

Another possibility to consider -- though I think Detroit is a bit chilly for me to be really happy with this one -- is roof mounted air to minisplit heat pumps for each unit. The big downside to that one -- besides the fact that it might just be too cold for them to provide enough heat -- is that your electrical system might not be able to handle the load. Your main entrance would have to be on the order of 600 to 800 amps 240 volt.

leonz

Hello and good morning Detroit 66,

I am not sure US pipelining.com provides small bore CIPP pipelining for hot water heating but it would not hurt to check with them.

Are the exterior walls wood, concrete or cinderblock walls? If they are of concrete or cinderblock construction are there glazed clay capstones covering the top of the walls or is sheet metal and rubber membrane used to cover the sheet metal?

Are the second floor ceilings concrete ceilings with corrugated steel plate using suspended ceilings?

Is the roof a rubber membrane roof with a pebble base with aluminum asbestos roof coating or rubber roof membrane alone?

What type of roof drains are there?

Are there scupper drains if there is a high wall at the roof line?

Do the sewer vents for the first and second floor apartments share a common vent on the exterior walls or are they within the interior?

Does the building make use of an accessable utility chase in the ceiling for all common piping and wiring on the first and second floor?

Is there a central thermostat for both floors or are there 16 thermostats?

What size electrical service is used for each apartment?

Is the buildings wiring to each of the apartments enclosed in conduit with a separate main breaker for each apartment and service panels for each apartment?

One option would be to use closed cell foam oxygen barrier pex in 4 inch drainage tubing that could be buried along the building wall and run up the exterior wall to the second floor to each apartment.
The black pipe could be hidden with plantings of ivy that would conceal it.

The last time I checked the closed cell oxygen barrier pex was over $15.00 a foot but of course with a large volume purchase you would save money on a per foot basis.

EdTheHeaterMan

Just throwing that out for discussion. We owned a flat roof multi family building and made the upgrade to a pitched roof to solve the 70 year old roof leaks that constantly plagued the building.

Perhaps using @Jamie Hall’s roof pipe idea with the new roof may be an option. Also the boiler(s) can be installed in the new attic where there’s more room for the equipment

Multiple small boilers are often less expensive than a commercial boiler

EBEBRATT-Ed

Whatever you do is going to be big $$$. No way around it.

I think if I had some one giving me a price of 50K and they could do the RIGHT job for that price that would be the way to go.

Intplm.

@Detroit_66

Along with burying the pipe well below frost level and adding baseboard heating.

This might be a type of product to use.




Check it out?