Confirm Short Cycling

ChicagoCooperator

I want to make sure I have my terminology correct: short cycling is, generally, when the boiler/burner runs continuously, the burner will stop for a short period (2-3 minutes) and then restart "full force" again.



This happens on our system, a two-pipe steam with a 1926 Heggie-Simplex Boiler and, primarily, Trane Concealed Heaters, i.e. convectors (and some poor modifications...). We have a condensate pump and return traps (I think that's the correct term) in the boiler room.  It happens especially around the night set-back time and sometimes the burner will shut down and need to be restarted (the "FSG Alarm" light is on) - which I gather is to do with combustion. Generally we've (my fellow board members and I) been able to restart it with no trouble, however, we still haven't gotten a cause. At the moment the boiler has been running pretty much non-stop due to the cold and a lot of the noises in the system have disappeared from what I can tell.



I gather venting is the issue here - we've been getting uneven heating. My unit is often uncomfortably warm while others are cold (some of the issues, especially in this weather are leaky windows, wall AC units and "user error" in some units) even on the same risers. The system has been misunderstood and neglected badly for years so it's a task to get things on firm footing.



Our boiler guy has suggested a new controller ( <a href="http://www.rdcontrolsystems.com/brochure-downloads/broRF207.pdf">http://www.rdcontrolsystems.com/brochure-downloads/broRF207.pdf</a> ) - I'm not convinced yet this will solve the cycling and uneven heating yet. It will solve the problem of wind - our building has long north and south faces and when we got north winds the north side of the building gets cold but the controller can't anticipate it.



Obviously, since we have heat at the moment, we're low priority for our boiler guy at the moment, but our plumber is coming to check a failed convector and I will have him fix a leaky trap when he's here as well. I'm wonder if there are any suggestions for things he should check when he's here?

nicholas bonham-carter

Order of priority of repairs

What controls the system now?

When your building was first built, the heat would have been more even, with all the radiators getting steam at the same time. The first job is to return the system to its original state of operation. The last thing on the list will be a more sophisticated controller, as these devices are not able to function properly without the system being in a proper state of maintenance. We can help you here with good advice, as you bring back the system from the brink, step by step.

If you go to the library on the site here, you should find some information on the Trane system, which operates on extremely low pressure. There are also some good books in the shop here which will enable you to understand the basic principles of operation of the system, enabling you to judge the competence of anyone working on the system.--NBC

ChicagoCooperator

Heating Controls

We have a heat timer - model EPU or EPU-CH. We've eliminated the night setback because of the cold lately. I'm glad I'm not alone in my skepticism of new timer yet.



I was also going to add that there as several locations which either didn't get adequate heat shortly after the building was built or the system was never run correctly.



The location with added or replaced units is especially problematic over the driveways which need more insulation in the future. The other was one tier of bathrooms which depended upon a convective effect from two pipes (supply and return). Several have had single pipe radiators installed which we have mandated replacement of.

ChicagoCooperator

Hidden Vents

I'm also wondering if there are hidden vents at the top of the risers which weren't replaced when we replaced our steam traps last fall. 

ChicagoCooperator

Further Problems - steam vent and hot returns

I did more exploring last night - rechecked things I'd looked at earlier and found some things that might be problems.



There are four downfeed convectors on the first floor and one (the others have traps only) of them has a vent which is hissing and wasn't replaced along with trap replacement last spring. The convector in question also has a steam trap.



I've posted two photos of this - I couldn't get a shot of the side of the convector, it's accessible from a storage unit. The first one shows the general setup and the second shot shows the steam vent which seems to have a his. The convector has a side supply which has both supply and return connections at the end - I don't think there is any other way of doing it (It's a concealed unit fully plastered over on the room side with intake at floor and damper/register/grill about 6'-0" above the floor). The trap is directly above the connection for the return.



I should have also mentioned (can't believe that I forgot it yesterday) that the returns are generally hot, not just hot to the touch, but untouchably hot. We replaced almost all the traps in the spring except for, I think, two, which require more than just knocking a hole in plaster to access. I think those will have to be dealt with asap.

ChicagoCooperator

How much pressure?

NBC, how much pressure should the system be running at? I can't find anything specific to Trane other than the concealed heater literature in resources.



Here's some further photos showing the pressure gauge (while in operation). I can't get up close to the controls  (pressuretrol, right) - they're about 8'-0" up - to see the settings. When I went down about 20 minutes after this photo was take the needle had moved up to about 3 or 3-1/2. We've been told its at the correct pressure, but I'm not sure that's correct.



Also a better shot of the return setup. The returns all have F&T traps and merge into the pump (Hoffman I believe, with an ITT pump). The air vent is immediately to the left of the condensate return. It was "belching" a bit of steam when were were taking photos - less than last year but still some. The return rises up above the water line, turns, runs back, turns back down and then enters the boiler at the back.



The last two photos are of the return temperature sensor - the first shows it up close and the second shows a second device immediately above it. They're on the same pipe, the sensor is hidden in the second photo by the steel angle (supporting, I believe, an abandoned hot water storage tank).



One other tidbit about the system. I hadn't realized until this morning, but the one pipe radiators may actually be on the return side of the "pipe" heating for the bathrooms as there is a trap on the return line from those risers. The other bigger problem is that there is a one pipe radiator on the 8th floor on a riser which may not have a trap (I am going to investigate tonight).

nicholas bonham-carter

Hissing vents a cry for help

When main, or rad vents (on a 1-pipe system) can be heard, it is a cry for help from the system. Either the pressure is too high, or the venting capacity is inadequate. These are easily correctable, and will probably have less that a month's payback, considering the fuel savings.

The real question is:why have neither your boiler guy, nor your plummmmmmmmer fixed these first? It sounds as though you need a more expert pair of professional eyes on the whole system. If this system suffered these faults in its first years of life, the repair person would have been shown the door.

Contact one of the contractors listed in the find a contractor section here. Boiler whisperer Dave bunnel is one Chicago area expert, who comes to mind.--NBC

ChicagoCooperator

Two-pipe

It's a two pipe system! We got a proposal from Dave, but it was voted down (wah). We didn't have our current boiler guy when we replaced the traps, so he wouldn't have been aware of this vent. It's my understanding though, with two-pipe systems (and a main vent in the boiler room) that we don't need this one unless it's a special situation?

Jamie Hall

Pity Dave got voted down

since he's one of the very best -- and a good deal less expensive, in the long run, than the cheaper sort.  But that sort of arithmetic usually doesn't fly in a condo setup.



If you have really hot returns, you can't expect to do much else until you get those fixed.  Repair those traps.



And no, two pipe systems do not need radiator vents.  In fact, they can do more harm than good, particularly by concealing other problems.

ChicagoCooperator

Radiator Vents

I was surprised that this convector had a vent - none of the other two-pipe radiators or convectors do, nor do the other three downfeed convectors on the first floor (the steam mains are just below the ceiling of the first floor - there are only four "habitable" rooms, everything else is storage or laundry, heated by exposed steam mains) . There was inadequate heating from day one (or inadequate operation) and a lot of bathrooms had one-pipe radiators added. My next task is to determine if they are on the supply or return - there is a trap on the return from the risers. The other one-pipe radiator I know of I have to do some exploring above the ceiling on the first floor to see how that is laid out - that may be the culprit. 

nicholas bonham-carter

Condo board decisions

Why was it that Dave's proposal was voted down? Was it because :

1.the residents are happy with the operation as it is?

2.they enjoy the higher fuel bills they now pay?

3.they don't mind the impact of a poor system on the future sales price of their condos?

What is the state of the rest of the building-roof etc?--NBC

ChicagoCooperator

Mainly money

Money was the main decision - the building has been severely neglected for years and we also have to do major tuckpointing to fix inept workmanship to correct infiltration problems - we're not a wealthy building by any means. Two board members (myself included) are active and trying to force things to get done, there's just a lot of inertia against it - not just on the board. A lot of shareholders have modified heating in their units and will be loath to change them or change their routines even if they have discomfort.



I told the other board members that we need to get the heat working right this morning - one unit has been around hovering in the low 60's which is below Chicago's mandated heating level. I told them that we could get 311 (the City of Chicago's non-emergency contact number) called on us which would cause court costs etc. Hopefully that wakes them up a bit.

nicholas bonham-carter

Something helpful here?

http://www.dsireusa.org/incentives/index.cfm?state=IL&re=0&ee=0&spv=0&st=0&srp=1



Maybe there are low cost loans, or rebates for your improvements.--NBC

ChicagoCooperator

Thanks!

I know that some of the rebates are unavailable for two pipe systems, unfortunately.



We did get rebates on trap replacement this spring which was good.



I'll take a look and see if there is anything we can apply for - thank you for the link. 



We're inspecting the coldest unit tonight, they will probably not be happy to hear that the heating system hasn't been working as it should since they've lived in the building.

ChicagoCooperator

Air Vent

I'm still wondering why there is an air vent there. It looks like the wall was knocked away to get into the wall space to install it. I'm thinking it should be plugged. 

nicholas bonham-carter

system inspection

did the unhappy occupants vote yea or nay for Dave?--NBC

ChicagoCooperator

Actually

Actually one did.. It means change!



We've got some immediate tasks at hand. Steam is getting into the returns and we have to stop the short cycling.



1. Get rid of air vent on lobby convector.

2. Check all traps & replace as required.

3. Confirm 2 pipe radiator isn't on trapped line & remove.

4. Lower boiler pressure.

steamedchicago

it's people...

Condo and co-op associations are filled with people who'd rather spend $1000 a month forever than spend $10,000 once. It's particularly bad when they've been badly run, and there's lots of deferred maintenance that needs to be done, and no reserves to pay for it. Anyone who might be wanting to sell in the near future doesn't want to spend money on things they won't benefit from, etc.

ChicagoCooperator

Agreed

Also a problem in some buildings is owners who act like renters.



That's my building - I knew that going in, but I got a great price (and sales after mine have been for significantly more, so I did well).