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replacing asbestos with new insulation

eappleton
eappleton Member Posts: 111
Hi all,

Our 24-unit NYC coop is planning to have old pipe insulation with asbestos in the basement removed and replaced with new insulation. We have single-pipe steam. I would appreciate your thoughts on a couple questions:
  • Is it possible to do this work during the heating season? We are trying to get someone to finish the job by early November (over the course of a week), but weather might call for heat at some point when the pipes aren't insulated. I would expect that steam won't flow properly if the main steam pipes aren't insulated. And maybe it's unpredictable. I'm just wondering if we should absolutely not do the work during heating season.
  • When we replace the insulation, should we specify the insulation that should be used? What do you all recommend? We're willing to pay a little more if it's done right.
Thanks!
Eric
Single-pipe steam | 24 apartment, self-managed coop | Federal FST-40 Scotch Marine boiler | Carlin 701CRD burner | Heat Timer EPU-CH | Honeywell pressuretrols | Heating oil #2 (20% bio)

Comments

  • Jamie Hall
    Jamie Hall Member Posts: 23,170
    Well... yes it is possible to remove the asbestos when the system is running, although the fact that the pipes are hot will make it considerably more difficult. It won't affect the heating much.

    On the insulation -- yes indeed you should specify it. It should be 1 inch fiberglass, molded to fit the pipe or fittings. It should have a jacket and matching securing arrangements. State Supply has that sort of thing, but there are other suppliers as well.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • When the pipes are uncovered, it would be a good time to check the slope of the pipes just to make sure there are no sagging portions, which could cause water hammer.
    A magnetic level would be handy for this.—NBC
  • JUGHNE
    JUGHNE Member Posts: 11,042
    I would ask the people removing the old insulation about hot pipes. I have heard some comments about the plastic bag & glove removal method being difficult with steaming hot piping.

    1" is the minimum FG thickness for steam.
    Some codes?? require thicker insulation.
    It gets to the point of diminishing returns for the thickness upgrade.
    Some believe thicker at the boiler piping is worthwhile.

    NBC's suggestion is certainly valid. I have checked slope on old piping without insulation and nearly doubled the number of hanger supports. The pipe itself can get a "belly", giving you pockets of water that could eventually cause water hammer.

    Some insulation abaters may also disconnect hangers or knock them out of adjustment.
    New England SteamWorks
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,455
    1" is ok, 1 1/2" or 2" would be worthwhile especially if the basement is cold. they could easily price it for you both ways. As @JUGHNE mentioned the first inch does the most insulating. Ask the insulator if working on hot pipes is an issue. it won' bother installing the new removal may be an issue
  • eappleton
    eappleton Member Posts: 111
    Thank you, everyone! This is hugely helpful.

    My takeways:
    - Go ahead and do the removal and installation now if the crew is up for it.
    - Check slope of pipes when the insulation is off. I can search the Wall to make sure I have the right slope.
    - Check to see if hangers have been removed. Make sure they are replaced.
    - Use 1" minimum, fiberglass insulation, molded to fit the pipe or fittings, include jacket and matching securing arrangements. Maybe check local code to see if thicker is required.

    insulation (choose 1" minimum and appropriate pipe size): https://www.statesupply.com/pipe/insulation/fiberglass/pipe
    Fittings for steam pipe insulation: https://www.statesupply.com/pipe/insulation/fiberglass/fitting
    Jacketing: https://www.statesupply.com/pipe/insulation/fiberglass/jacketing

    Question: Should we specify that jacketing is used across the full length of insulation through the basement, or is it important just in certain areas? The pipes travel through residents' storage bins and other public areas of the basement.

    Thanks again,
    Eric
    Single-pipe steam | 24 apartment, self-managed coop | Federal FST-40 Scotch Marine boiler | Carlin 701CRD burner | Heat Timer EPU-CH | Honeywell pressuretrols | Heating oil #2 (20% bio)

  • Larry Weingarten
    Larry Weingarten Member Posts: 3,273
    Hello, Regarding insulation thickness, energy will probably not get cheaper. You are replacing insulation and the new stuff should last a long time, maybe 40-50 years? Seems it makes sense to insulate based on what energy might cost decades from now, so the insulation job isn't obsolete before the end of it's design life. So, to put it simply, if you can fit in the two inch stuff, it will more than pay for itself in the long run. B)

    Yours, Larry
  • eappleton
    eappleton Member Posts: 111
    Good point, Larry. I wish we could insulate the pipes all the way up the radiators.
    Single-pipe steam | 24 apartment, self-managed coop | Federal FST-40 Scotch Marine boiler | Carlin 701CRD burner | Heat Timer EPU-CH | Honeywell pressuretrols | Heating oil #2 (20% bio)

  • Canucker
    Canucker Member Posts: 722
    I would definitely cover the insulation where it could get damaged. Sounds like that could happen on the pipes in the public areas
    You can have it good, fast or cheap. Pick two
  • Ken D.
    Ken D. Member Posts: 836
    I do hope the asbestos will be properly and safely abated and disposed of.
  • eappleton
    eappleton Member Posts: 111
    Hi all,

    An update and a quick question. Thanks again for the fantastic advice regarding asbestos removal and reinsulation. I'm so thankful that we had your advice. After the asbestos abatement (done with a permit, proper disposal and all), a team came through and added new pipe hangers in a number of places in our basement, also checking to make sure the pitch was good. We are halfway through the insulation now and it seems that the job is being done well. 1 1/2" insulation on 2 1/2" pipes, 1" insulation on smaller pipes, adding elbows, tape and mastic at the joints.

    Question: We had insulation on some return pipe that ran along the floor. It was removed by the abatement crew. The insulation crew says that it isn't needed and doesn't plan to insulate returns at floor level. It seems to me that we want to insulate anywhere a pipe is exposed, even if it's a return. Warmer water coming back to the boiler means less fuel needed to bring it back to steam. Am I wrong?

    Thanks,
    Eric
    Single-pipe steam | 24 apartment, self-managed coop | Federal FST-40 Scotch Marine boiler | Carlin 701CRD burner | Heat Timer EPU-CH | Honeywell pressuretrols | Heating oil #2 (20% bio)

  • Jamie Hall
    Jamie Hall Member Posts: 23,170
    Well, no, you're not wrong in principle, but there is very little heat actually in the condensate -- so most folks figure it's not worth the cost and effort.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    eappletonCanucker
  • Larry Weingarten
    Larry Weingarten Member Posts: 3,273
    Hello, If you knew the return temperature and the ambient temp in the basement, you can easily figure the delta T. From there, measure the exposed pipe length and you can now figure the actual heat loss... and cost of that lost heat. That can guide you in deciding whether or not to insulate the returns. I like to over-insulate most everything as the price of energy seldom goes down... but I'm a bit fringe in this way :p

    Yours, Larry
  • eappleton
    eappleton Member Posts: 111
    Very helpful. Thanks, Larry and Jamie. We won't insulate the floor returns for now, but a friend is going to bring over an infrared thermometer so we can figure out the heat loss. Maybe we'll do some of our insulating after the crews leave.
    Single-pipe steam | 24 apartment, self-managed coop | Federal FST-40 Scotch Marine boiler | Carlin 701CRD burner | Heat Timer EPU-CH | Honeywell pressuretrols | Heating oil #2 (20% bio)

  • eappleton
    eappleton Member Posts: 111
    Hi, it's me again. A weird problem has cropped up in the last couple days. We suddenly have issues with hot water. This has been as issue for a few apartments over the years, but we don't usually get too many complaints. Since we've had the new insulation installed (on steam pipes and hot water pipes), we've had a rash of complaints (from all over the building) in the last two days about running the water for a long time before the hot water arrives.

    As some background: We just removed asbestos and then had new fiberglass insulation installed. The insulation crew was slow, so the pipes have been half insulated for a couple weeks with not too many complaints. They are currently pretty much finished, with some insulation still missing on the boiler and steam mains close to the boiler. Our hot water is provided by the boiler. We have never had a circulating pump in the system. 24 apartments, 4 floors, single-pipe, analog Heat Timer controls.

    Somehow it seems that the hot water circulation is worse than it was when the insulation was totally missing. We've looked at the boiler and all seems fine. The thermometer coming on the pipe leaving the mixing valve is showing 140 degrees.

    Is there any reason why adding better insulation would change the circulation in hot water?

    Is there anything we might be able to adjust in the short term to help the situation?

    Thanks!
    Single-pipe steam | 24 apartment, self-managed coop | Federal FST-40 Scotch Marine boiler | Carlin 701CRD burner | Heat Timer EPU-CH | Honeywell pressuretrols | Heating oil #2 (20% bio)

  • JUGHNE
    JUGHNE Member Posts: 11,042
    Recir pump is off or failed?
    Someone shut off a valve somewhere in the return line?
  • eappleton
    eappleton Member Posts: 111
    We have never had a recirculating pump. Maybe we could use one, but it doesn't explain the big increase in problems now.

    The shut off valve possibility is interesting. If so would the problem be intermittent? Sometimes, everyone is getting plenty of hot water. Other times, many people (not sure if it's all) are not.

    I'm wondering if there might a problem with the mixing valve. How might we know? Would that explain intermittent problem? Maybe the temperature drops when we weren't there to look at the thermometer leaving the valve?
    Single-pipe steam | 24 apartment, self-managed coop | Federal FST-40 Scotch Marine boiler | Carlin 701CRD burner | Heat Timer EPU-CH | Honeywell pressuretrols | Heating oil #2 (20% bio)

  • Jamie Hall
    Jamie Hall Member Posts: 23,170
    First things I'd check would be the mixing valve and the aquastat, the one to make sure it isn't stuck (they do) and the second to make sure that it's actually keeping the boiler warm. The first isn't related to the insulation; the second might be, as the boiler might be running less with the new insulation, and the aquastat might be either set too low or failed, which could have been masked by not having the insulation.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • eappleton
    eappleton Member Posts: 111
    That's really helpful. I had forgotten about the aquastat. I was under the impression that I only needed to worry about the aquastat in the summer, so it may be set incorrectly.

    A technician is coming tomorrow. We can ask him to look at it. Anything special he should do?
    Single-pipe steam | 24 apartment, self-managed coop | Federal FST-40 Scotch Marine boiler | Carlin 701CRD burner | Heat Timer EPU-CH | Honeywell pressuretrols | Heating oil #2 (20% bio)

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,455
    Possibly someone inadvertently shut a valve or knocked a control out of adjustment while insulating
  • Neild5
    Neild5 Member Posts: 167
    eappleton said:

    We have never had a recirculating pump. Maybe we could use one, but it doesn't explain the big increase in problems now.

    The shut off valve possibility is interesting. If so would the problem be intermittent? Sometimes, everyone is getting plenty of hot water. Other times, many people (not sure if it's all) are not.

    When the furthest faucet is on and gets hot water all the closer faucets have hot water so it would appear intermitent.

  • eappleton
    eappleton Member Posts: 111
    Hi again,

    I have some updates that I would appreciate some help with. We've had a major issue with intermittent hot water over the course of the last two weeks. I wonder if someone might let me know if my information/analysis is in the ballpark.

    A boiler technician came yesterday to look at our hot water issue. He looked at the mixing valve and said he didn't like them since they often got stuck. Said he stopped using them. But he didn't think it was the culprit.

    Hot water, cold water, mixing valve (sorry about the photo quality):


    He discovered that the water level was low. We filled it so that it was above the coil (?), where the hot water pipe comes out of the boiler. After an hour, the water line on the gauge had dropped by an inch. The technician believes we have a pretty serious leak in a return line somewhere, estimated that we're losing 20 gallons an hour. I guess our super has been topping off the boiler and didn't realize that this was a sign of an issue. It seems to be dropping faster than before because our super is now having trouble keeping up with it manually. We walked through the basement with the technician following the returns by feeling the heat on the concrete floor. They are mostly just below the surface of the floor.

    The technician told us that we are having trouble with hot water because the water line is falling below the coil. My understanding is that we get hot water when we are producing steam, but in between heat cycles, the water cools off. We turned the aquastat up to 180, but it may not be helping much if the water line is still below the coil.

    Repairing the leak:
    My understanding is that we can use an infrared camera (Amazon is sending one) to take photos of the floor throughout the basement to find the leak. Anywhere we see heat pouring outside the pipe would probably be a leak. Is it more complicated than that?

    I'm wondering if a repair like this can be done quickly, during heating season. My gut tells me no, that one thing might lead to another, one fragile pipe leads to another fragile pipe, and suddenly we're ripping up the entire basement floor. (Not us, literally, but the company we hire to do the repair.)

    Circulating pump:
    Meanwhile, we had previous advice to install a circulating pump to address long wait times for hot water in a minority of apartments (We have never had a circulating pump and have had complaints every once in a while, but nothing like what has happened in the last week). We have collected estimates and are ready to decide whether to do this work. Now would be the time to do it because we have an insulation crew that can come behind and seal everything up after the work is done.

    My intuition is that the circulating pump probably won't help the current issue much but it's a good time to do the work and it will help all apartments be more comfortable, save water, etc. once the current crisis is resolved.

    Location of new pump:


    Temporary fix for the hot water:
    The technician pointed out that we could raise the automatic water feeder so that it keeps the water level consistently above the coil. We wouldn't have to manually add water and the hot water would function properly. This is a simple repair, just changing the length of the nipples on the top and the bottom of the water feeder.



    One thing I don't like about this fix is that it would hide any future leaks since the water feeder would automatically pour in fresh water. But since we know there is a leak now, we can schedule the plumbing work in the spring when it would be less disruptive.

    So, does this approach make sense?
    - Install circulating pump (now)
    - Move water feeder (now)
    - Repair leak (spring)

    Or should we try something else? Or do we need more information?

    Thanks so much! You all are a lifeline in stormy, icy seas.

    Eric

    Single-pipe steam | 24 apartment, self-managed coop | Federal FST-40 Scotch Marine boiler | Carlin 701CRD burner | Heat Timer EPU-CH | Honeywell pressuretrols | Heating oil #2 (20% bio)

  • Jamie Hall
    Jamie Hall Member Posts: 23,170
    On moving the water feeder. That would work... as a bandaid. Put a meter on it, or get one with a built in meter.

    However.

    I've never known a leak to get better with time. I'd be concerned (to put it mildly) that what now appears to be a pretty good sized leak might turn into a catastrophic leak, and leave you with no heat at all. At the very least I would check and make sure that your low water cutoffs are working...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • eappleton
    eappleton Member Posts: 111
    Thanks, Jamie. I appreciate the advice. I didn't realize we could put a meter on the feeder.

    Can the leak be repaired during heating season? Is it a good idea?

    And sorry for my ignorance, how can we make sure that the low water cutoffs are working? Drain the boiler while it's running? That doesn't seem right...
    Single-pipe steam | 24 apartment, self-managed coop | Federal FST-40 Scotch Marine boiler | Carlin 701CRD burner | Heat Timer EPU-CH | Honeywell pressuretrols | Heating oil #2 (20% bio)

  • Jamie Hall
    Jamie Hall Member Posts: 23,170
    The leak can be repaired during the heating season, but I'd pick a warmer day than today... if you can find it. You are quite right in thinking that you are going to open a can of worms -- you are -- but it might be sufficiently localized that some type of patch could be used.

    The low water cut off can be checked by simply draining enough water to be just below it. The boiler should shut down. On some -- McDonnel Miller float types for instance -- there is a blowdown valve on the cutoff body which can be used to do that. If the boiler shuts down -- as it should! -- I'd be inclined to let it cool some before adding water to start it back up again.

    A nice picture of the boiler controls, showing the low water cut off, and I'd be able to make a more detailed suggestion...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • eappleton
    eappleton Member Posts: 111
    Thanks, Jamie. We're going to try it this weekend. I'll take a photo tonight and give you a better view.

    I started a new thread for the leak (missing water).

    Eric
    Single-pipe steam | 24 apartment, self-managed coop | Federal FST-40 Scotch Marine boiler | Carlin 701CRD burner | Heat Timer EPU-CH | Honeywell pressuretrols | Heating oil #2 (20% bio)