Baseboard and Radiators not heating

KevinWyman

I became an owner of a condo in a 6-apartment building back in 2021. Our apartment is on the third floor, there are two apartments per floor. The building dates back to the 1957 time frame. Prior to our purchase, the building replaced the boiler with an oil-fired Weil-Mclain Series 80 boiler. Immediately after closing I was hit with an unexpected "special assessment". This was for new return piping in the basement. The piping in the basement forms a "U" shape with the steam piping and the return and steam have traps and air vents at the end of the U with the new return piping meeting in the middle and combining to return to the boiler feed pump.

The issue we are collectively having is certain units have radiators that don't heat up thoroughly or are not providing enough heat (and that is with this mild weather). I re-read Dan's book recently and did find a few things that concerned me with the system: boiler cut-in is set for 1/2 psi and cut-out control at 5.5 psi. Is this possible affecting the no or low heat in the lower floors?

Also, on the pump the vent pipe is only vented at the end of the pipe; there is no vent at the top of the horizontal run. I will also say none of the pipe is insulated except a small 3-foot section above the main walking area for head protection. The boiler is in a pit and the pitching seems adequate to me.

I can't really tell if there are steam traps on the radiators. I will say that our unit, top floor has not experienced any issues with heat although the "front room" which has two windows, fireplace and a door out to a deck/balcony is the coldest room in the apartment. Units 2 and 4 on the North side of the building, are complaining that this room in their apartments is too cold to habitat in during the colder weather. Both of these units, at some point in the past, had changed out the radiators for cast iron baseboard. Unit 2 has numerous rooms that are not heating sufficiently.

My question is where to look to address these cold baseboard radiation units. The other unit on that side of the building, #6 is not reporting the same issues although she says the radiators feel cold on the bottom and warm to hot on the top. I did purchase everyone an infrared heat gun to measure the temperature gradients of the individual radiators, although we are waiting a cold snap to make sure the boiler is producing steam.

The association also installed a Nest thermostat system with a sensor in apartment #3 that controls the Nest thermostat that is in the basement. I think there was an additional sensor in unit 6 but that has been placed in unit 3 when the original sensor broke or possibly couldn't be connected to the thermostat. I would like to replace the Nest with an Ecobee that would be placed in unit 2, the first floor North facing apartment, we could also add sensors in every apartment to get a feeling for how well the system is working or use them as averaging sensors. My feeling is that residents should be using their individual radiator valves to control the heat in the apartment. I think the Nest was the brainchild of a resident who no longer owns a unit and was done to save some oil.

leonz

Can you take pictures of the boiler and the piping in the basement so we can see what you have in the basement?

Jamie Hall

Ok. Two comments right off the bat. First place at least one of you radiators has a vapour type return fitting. The whole system may have been intended to be vapour. So... are you sure of the cutout pressure? You quote 5.5 psi. That is not just high, it is outrageously high. Please double check. The cutout should certainly be no more than 1.5 psi, not 5.5, and even that is probably too high (but is as low as you can go if you have a pressuretrol rather than a vapourstat).

Second, I'm not a bit surprised that the units with baseboard are having trouble. Baseboard is very difficult to get working properly with steam, even when everything is pitched correctly and trapper correctly and all that. Worse, unless there is a lot of baseboard, there may simply not be enough radiation.

KevinWyman

The building was built in 1957 according to town records. The apartments number 6 with two per floor, three floors; 1, 3, 5 face South and 2, 4, 6 face North. The steam system is a two-pipe system. Prior to our purchase of a condo in the building, the HOA had replaced the boiler with an oil-fired Weil Mclain Series 80 Series 1 580 and a boiler feed pump system. As soon as we closed, we got hit with a "special assessment" to replace the return piping. That work happened over the summer, and it resulted in new main return line to the boiler pit, new steam traps at the ends of the steam mains and return lines and new vents as well. The boiler is centrally located on the North side of the basement with the steam mains branching out in a "U" to the other side of the building. The returns follow the steam legs back to the South side of the building and there are trapped with the steam mains and the vents. A central return line combines the two sides of the distribution system.

During the winter of '22-'23 we had no issues with our unit, #5 on the third floor of the building. Apparently, units 2 and 4 experienced different levels of heat with the biggest complain coming from unit 2. I will say that both units have cast iron baseboard that perhaps replaced their radiators in the past. Nothing recent with the current owners. The main problem is the front living room. That room has two windows, a door to a porch, a fireplace. It is definitely the coolest room in our unit but not unbearable though. For units 2 and 4 the complaints are that the baseboard is cold or cool especially versus other radiators/baseboard in the units. The unit above, #6 has a radiator in that room and has reported that the top of the radiator is hot and the bottom is cold. I am not sure about traps on these baseboards nor even on the other units. I will leave some pictures of my unit radiators. What should I be looking for to solve the issue for these two units?

I did re-read Dan's book over the weekend and did find some issues that may or may not contribute to the situation. The feed pump has no vent in the horizontal portion, just an opening to atmosphere as the line curves down behind the tank. The cut-in looks to be at 0.5 psi and the pressuretrol is set for 5.5 psi. Too high? The boiler is bled once a week into a bucket by one of the residents, the water in the sight glass looks clear (I've seen worse). There are only two vents on the system (I will post some pictures below).

The other issue is the control of the boiler. Someone installed a Nest thermostat in the basement and two sensors, one in Unit #3 and one in unit #6. The sensor in 6 was moved to 3 because the sensor broke or couldn't communicate with the Nest so there is only one sensor now in unit #3 and it is supposed to control the thermostat. Some residents have access to the app and can modify the setpoint. This was done a few years back to combat rising fuel oil costs. My thought is to move or replace the Nest (Ecobee plus sensors per apartment) into the coldest unit, North facing first floor apartment, Unit #2.

I have also asked the residents to take temperature readings of their radiators/baseboards while the boiler is operating and purchases infrared thermometers to take surface readings. We are waiting for a cold snap where the boiler will be on for a prolonged period and everyone is at home to take "simultaneous" readings. I have been in touch with the people who did the piping and flushing work and they want to essentially do this work so I am trying to get the residents to pitch in.

What is the place I should be looking to solve the low h
















eat in unit #2 and the single units in Unit #4? Traps, Vents?

Thanks for your advice.

Neild5

It looks like you have 2 pressuretrol units, the one with the clear cover is a safety shut off, the smaller gray one is the controller, can you get a better picture of that one, preferably with the cover taken off as there is a dial inside.

Jamie Hall

Ok. Two comments right off the bat. First place at least one of you radiators has a vapour type return fitting. The whole system may have been intended to be vapour. So... are you sure of the cutout pressure? You quote 5.5 psi. That is not just high, it is outrageously high. Please double check. The cutout should certainly be no more than 1.5 psi, not 5.5, and even that is probably too high (but is as low as you can go if you have a pressuretrol rather than a vapourstat).

Second, I'm not a bit surprised that the units with baseboard are having trouble. Baseboard is very difficult to get working properly with steam, even when everything is pitched correctly and trapper correctly and all that. Worse, unless there is a lot of baseboard, there may simply not be enough radiation.

Jamie Hall

Having found where you moved this to...

As @Neild5 said, need a better picture of the operating pressuretrol -- the one with the metal cover -- to see what you are actually running at.

The vents you picture are not main vents. They're cute, but they're not main vents. You need at least a Gorton #1 for that, or possibly even a #2

EBEBRATT-Ed

I doubt the building was built in 1957. Some of the radiators have steam traps and some have what look like vapor fittings on the return.

By 1957 vapor was long gone

bburd

The radiator style and other construction features look more like 1917 than 1957. 

KevinWyman

The boiler pressure controls.

KevinWyman

I did find a No. 75 Vent Rite on the floor today, possibly the old vent

Erin Holohan Haskell

@KevinWyman, I've merged your duplicate posts into one here. Your other post was temporarily held in spam. This sometimes happens if a post is edited too many times within a short period. Sorry for the inconvenience and thanks for your patience!

KevinWyman

Better picture of the cut in control. Looks like 1 psi. The boiler was turned on while I was there (thermostat went from 68F to 70F and ran for about 10 minutes before the thermostat was satisfied. I ran around getting temperature readings. 215F on the steam pipes and from 205 to 98 on the return risers.

KevinWyman

I'll got back tomorrow with my screwdriver and take the cover off the Honeywell controller.

Jamie Hall

If no one has messed with the differential dial in the grey pressuretrol, you should be sort of OK.

I do see another potential problem, though. That is a very cute little boiler, and it is now equipped with what I suspect is a vented feed tank (which it probably didn't need...). The problem is wet returns and the drips into them. It is very likely that when the system was originally set up, it had a bigger boiler with a much higher water level. The wet returns would have been wet, and that would have made a water seal between any drips from the steam mains and the dry returns. Without that water seal, you will be getting steam into the dry returns, and that will shut the heating down.

Would you go all around the basement level and examine what drips you have and what wet and dry returns you have and let us know?

KevinWyman

Well I would say the service folks have messed with the controller. See the picture. I couldn't get the dial out of the box using modest force and didn't want to force it. I also included this time a picture of the service tag where last year they set it down to 3 psi.

As far as the returns, I will post additional pictures but it looks like to me, using a small laser and doing me best to keep it level and transfer the boiler water line to the common return pipe, it looks like the horizontal run is below the water line of the basement as it turns from vertical to horizontal. The two other main returns are well above the water line.

You can also see that the returns originally ran under the basement floor (and had been repaired at least once) before being abandoned. The new return line is higher than the previous line, I assume because the installer wanted more pitch back toward the boiler.

We held a meeting last night to discuss the issues that folks are having. First floor apartments in general are cold to the point where they are wearing coats in the winter and using supplemental heaters. The issue on the second floor could be a broken valve but that is still to be determined i.e. if the valve is open since the handle broke when attempting to turn it. There is an old air vent on that baseboard section. Third floor apartments generally have heat when the boiler is running. One apartment on the second floor, #3 has said that every since they moved in in 2016 the heat has been poor. My adult son termed this a "Frankenstein" system and I think that may be the case. Although the building department lists the building as circa 1957, other buildings date to the 1920s. So this may have been originally a vapor system but over the years, traps were added where radiators had issues.

I also have included a work-in-progress of the layout of the system: main steam lines are 3 1/2" the returns are 1 1/2" to the traps and to the common 2" return line. Brown is steam, black is return and green is copper pipe return. I have most of the locations of the risers but need to transfer them to my drawing.

neilc

those Ptrols should be on much taller nipples so they're not sitting in that trap water,

Jamie Hall

The laser (great gadgets) shows that those wet returns are low enough. Not by much. Or they would be, if it weren't for the condensate receiver. What governs is the water line in the condensate receiver -- and they aren't low enough.

The simplest thing to do would be to raise the condensate receiver so that the bottom was a foot or so above floor level -- not pit level. That would at least let those returns be wet, which they need to be.

Although I still wonder whether you need it at all...

As a side note, many vapour systems had traps. And needed them.