Need help with balancing a steam system (first-time poster)

rsilverst

Hi there — I have looked for answers to similar issue that what I have, and did not see them. I have lived in my home since April. It’s 1929 brick house with 2 stories and a basement, 2400 square feet total. We’re in Seattle, where it (usually) does not get very cold.

We have a service company who has already done maintenance for us when we first moved in (Carlson Mechanical), and they were the original installers of this system in 2003. They are old-school and do seem to know their stuff quite well.

Here’s the issue: Now that we’re in a cold snap in Seattle, our second floor is getting much warmer than the main floor. We typically set the thermostat (White-Rogers) at 69 during daytime and 65 at night. While the system is holding the main floor temperature at the setting nicely, the second floor is getting much warmer — it was 75 last night, while the first floor was 65. Our attic is very well-insulated (just had it redone), but I suspect the walls of the house are not, and I know for a fact that our windows and doors on the first floor are extremely leaky.

We have the vents in 3 bedrooms on second floor set to Slow. The vents on the first floor were all on slow or medium. The radiator in our dining room is less than 10 feet away from the thermostat, and it is the first radiator almost directly above the boiler, maybe about 8 feet away, and it’s 3.5-4 feet long.

A couple of notes (and I attached photos as well):

I checked cycle times before the cold spell (when we were in the 40s). The typical behavior for the system is that it would do 4 cycles of 10 minutes each (full cycle length off + on, about 6 on + 4 off). Then it would stay off for 30-40 minutes. Then repeat. During those shorter cycles, it was like precision clockwork, almost to the second. The longer off time was variable.

The temperature always reaches setting before it cycles (afaik). So I don’t think we’re cycling due to hitting pressure limit.

It seems like all of the vents on our radiators are the same size, despite the radiators not being the same size — though it is possible that I am not discerning the difference in size because I don’t know what I’m looking for (diameter? Length?).

One of our radiators, a very small one in second floor bathroom, is missing the cap on the vent, which I assume means it’s fast venting all the time (not sure how much that small radiator could factor into this).

I drain 3-5 gallons of water from the radiator every week or so, per the recommendation from the service people (they said to do it at least monthly, and more is better during heating season).

Thank you for any suggestions. And my apologies for what I am sure is severe ignorance at this stage. I’ll learn the system!





Typical vent on individual radiator (this is the dining room one near the boiler and thermostat)


Main Vent

Gordo

It looks like the first thing you are going to need a new main steam vent.
What is pictured is a Hoffman #79 air vent for a hot water system.
Pretty sure that's not the correct vent for your system.
What most likely should go there is a Gorton # 2 steam vent or equivalent.

bburd

When you insulated the attic, you greatly reduced the heat loss from the upstairs rooms. Most likely the radiators there are now larger than needed, and out of proportion with the ones downstairs.

Installing an appropriate main vent and speeding up the venting of the downstairs radiators should help. If you speed them up too much, you may get gurgling and water spitting from the air vents, so make gradual adjustments. Likewise, slow the venting of the second floor radiators.

The good news is that your near boiler piping looks quite good, which is rare these days on newer installations; so you should be getting dry steam and the system should run quietly.

ethicalpaul

I drain 3-5 gallons of water from the radiator every week or so, per the recommendation from the service people (they said to do it at least monthly, and more is better during heating season).

What the what?!?

EBEBRATT-Ed

I agree with @ethicalpaul you should not be draining water from the boiler or radiator every week.

I agree that the insulation may be contributing to the second floor being warmer but that is somewhat unusual being farther from the boile second floors are usually cooler

I would speed up the venting downstairs a little at a time....make small changes and marke down where they are set now so you can return to the old settings if need be. Second floor I would cut back on the venting again small changes.

Your thermostat location is not ideal being close to a radiator but that would usually lead to under heating not overheating

rsilverst

ethicalpaul said:

I drain 3-5 gallons of water from the radiator every week or so, per the recommendation from the service people (they said to do it at least monthly, and more is better during heating season).

What the what?!?

In some paperwork (handwritten) from previous owner that came with the house, it said to move the lever on the back left corner of the boiler to drain some water into a bucket at least once a month. There’s a feed system that automatically refills it after the low-water level valve kicks in and shuts off the boiler. When the service person came over to do maintenance, they confirmed what was written (probably it was their guidance that had been written on the paper). Can you help me understand why I shouldn’t be doing that? I was just trying to follow instructions

rsilverst

Gordo said:

It looks like the first thing you are going to need a new main steam vent.
What is pictured is a Hoffman #79 air vent for a hot water system.
Pretty sure that's not the correct vent for your system.
What most likely should go there is a Gorton # 2 steam vent or equivalent.

Regarding this valve — any ideas as to why they’d have a water system valve on there instead of a steam system valve? The people who serviced it recently were the original installers from 18 years ago, and I would *guess* that they’d have put the correct type of vent on there? Or if it had been changed for some reason by the previous owner, I would *hope* that they’d recognize it… is this a common mistake made on systems? I don’t think this is something I’d try to do myself, obviously — so I would have to be calling the service people and saying “Do I have the wrong kind of vent?” (It certainly is strange)

Thank you!

EBEBRATT-Ed

The note is telling you to blow down the low water cutoff (I am assuming) confirm this with your service tech. If so that is fine.

Someone could have inadvertantly installed the wrong vent.

ethicalpaul

Yeah, you said radiator, so I was confused. Also 3-5 gallons per week is too much even for a float LWCO if that’s what you have?

BobC

Hoffman #1 radiator vents are well made but they have a flaw. Then you loosen the screw to adjust the venting rate you will notice there is a lot of slop so after adjusting make sure the cap is centered on the valve body. This will ensure you get the venting rate you want.

Do what you can to better seal the doors and windows and increase the venting rates on the first floor to shorten the run time of your boiler.

Bob

KC_Jones

There doesn’t appear to be a float type LWCO on that boiler so you should not be taking any water out of that boiler on a weekly or monthly basis.  Yearly at most as part of an annual service to verify valve function and get the crud out of the low areas.

Draining water brings in plenty of new water filled with oxygen that will create more corrosion inside the boiler, shortening its life.

dabrakeman

You should be able to get a system balance with the adjustable Hoffman 1A's but first get a proper steam main vent on the system. Don't know the size and length of your main but it seems you have one main for a two story home so likely you will need at least 1 or 2 Gorton #2's.

If you remove the cap from the Hoffman 1A and look at it you can see it just has a nautilus shaped flat section that covers more and more of the vent hole as you turn the cap toward the slow position. You can line up the cap orientation visually to cover as much of the hole as possible and while t rying to keep the cap centered screw back on the top retention screw. Can play with it a few times. I have a similar issue in my 130 year old home where it is difficult to run the upstairs radiators without the upstairs getting too hot. This compounded by my liking the bedroom cooler... I actually took the cap right off and used a screw and a washer I fabricated to minimize the vent more robustly and completely. Balanced for me is on a normal cycle 75% radiator steam fill downstairs where the bedroom radiator will only be about 10-20% filled.

You could also try a Ventrite #1 vent on the upstairs radiators. They may give a little better low venting control since they can be set to actually fully close (zero venting).

rsilverst

dabrakeman said:

If you remove the cap from the Hoffman 1A and look at it you can see it just has a nautilus shaped flat section that covers more and more of the vent hole as you turn the cap toward the slow position. You can line up the cap orientation visually to cover as much of the hole as possible and while t rying to keep the cap centered screw back on the top retention screw. Can play with it a few times. I have a similar issue in my 130 year old home where it is difficult to run the upstairs radiators without the upstairs getting too hot. This compounded by my liking the bedroom cooler... I actually took the cap right off and used a screw and a washer I fabricated to minimize the vent more robustly and completely. Balanced for me is on a normal cycle 75% radiator steam fill downstairs where the bedroom radiator will only be about 10-20% filled.

This is immensely helpful -- I had been adjusting them to slow, but not taking into account the precise alignment, and from what I can now see, if you don't hold it in position to completely cover the opening, the default alignment will be only partially covering the hole at the lowest setting. We are seeing improvement by a couple of degrees already.

I also turned on a couple of radiators on the first floor that we had previously (erroneously) turned off. We have one under our kitchen sink, which is oddly in a cabinet that was built around it, and there was one by our front door that I had turned off because I was concerned about a lot of cold air leaking in through the front door. But I realize now that what I was doing was creating an unevenly heated main floor, which would result in the thermostat kicking in again a lot sooner (since farther away from the thermostat, it would not be at the set temperature. For the one under the sink... for now, we're cracking open the slide-out cabinet to let the heat into the kitchen, but I might go back to turning that one off, since it's truly a weird location. I am sure the original kitchen design had no cabinet enclosing the sink.

rsilverst

KC_Jones said:

There doesn’t appear to be a float type LWCO on that boiler so you should not be taking any water out of that boiler on a weekly or monthly basis.  Yearly at most as part of an annual service to verify valve function and get the crud out of the low areas.

Draining water brings in plenty of new water filled with oxygen that will create more corrosion inside the boiler, shortening its life.

I am attaching a few more photos here of the boiler, including the low water cutoff, and some of the instructions that came with it (as well as the hand-written ones that were provided by the owner). One curiosity is that the owner's notes said to flush it when it's cold, but our technician who was the original installer said to flush it while it's running so that it cuts off and turns the boiler off...

rsilverst

EBEBRATT-Ed said:

Someone could have inadvertantly installed the wrong vent.

Confirmed - I spoke with the company. They said that it should have been a Hoffman #75 or #76, which look identical to the Hoffman #79 and the technician must have grabbed the wrong part. Amazingly, this was likely installed 18 years ago... we are going to have it replaced. Thank you to everyone here for the good catch

bburd

Regarding the radiator under the kitchen sink, this is a common consequence of remodeling kitchens and putting in base cabinets where there were none before. You need to provide air circulation through the cabinet so the heat can get out into the room. This means both low and high openings. Warm air will rise up and out into the room, and cool air will flow in near floor level to replace it.

The usual solution is to replace solid cabinet doors with perforated metal grillwork doors. The grill material is available at any hardware store. This will reduce the heat output of the radiator compared to an open air installation, but it is much better than solid doors. You could also replace the usual blank-off panels just below the front edge of the sink with grill work to improve the airflow.

Keep in mind that access must be provided to the radiator supply valve and air vent for maintenance. 

rsilverst

bburd said:

Regarding the radiator under the kitchen sink, this is a common consequence of remodeling kitchens and putting in base cabinets where there were none before. You need to provide air circulation through the cabinet so the heat can get out into the room. This means both low and high openings. Warm air will rise up and out into the room, and cool air will flow in near floor level to replace it.

The usual solution is to replace solid cabinet doors with perforated metal grillwork doors. The grill material is available at any hardware store. This will reduce the heat output of the radiator compared to an open air installation, but it is much better than solid doors. You could also replace the usual blank-off panels just below the front edge of the sink with grill work to improve the airflow.

Keep in mind that access must be provided to the radiator supply valve and air vent for maintenance. 

Great idea -- We will look into this. It would actually look aesthetically okay if we do it well. For the moment, which was more of an experiment, I was keeping the sliding cabinet open a couple of inches. But that's obviously not a permanent solution

delcrossv

rsilverst said:

KC_Jones said:

There doesn’t appear to be a float type LWCO on that boiler so you should not be taking any water out of that boiler on a weekly or monthly basis.  Yearly at most as part of an annual service to verify valve function and get the crud out of the low areas.

Draining water brings in plenty of new water filled with oxygen that will create more corrosion inside the boiler, shortening its life.

I am attaching a few more photos here of the boiler, including the low water cutoff, and some of the instructions that came with it (as well as the hand-written ones that were provided by the owner). One curiosity is that the owner's notes said to flush it when it's cold, but our technician who was the original installer said to flush it while it's running so that it cuts off and turns the boiler off...

Your LWCO in the bottom picture needs weekly flushing like the instructions say. It's not necessary to verify the burner cutoff function every week so if you flush the LWCO on a cold boiler a couple of times a heating season, it's not a big worry (as long as it's flushed)

Gordo

I would ask that the #79 vent be replaced with a Gorton #2, as it better made than the current batch of #75s and it vents more for less money (and it will last longer).

EBEBRATT-Ed

I like the contractors typed instructions. Looks like they know what they are doing

rsilverst

Gordo said:

I would ask that the #79 vent be replaced with a Gorton #2, as it better made than the current batch of #75s and it vents more for less money (and it will last longer).

I shared this with our contractor and I'll see what they say. Thank you!

ethicalpaul

Why does this thing have a float LWCO and a probe LWCO?

and I’m afraid to ask, but why shut off a radiator that was near a drafty front door?

rsilverst

ethicalpaul said:

Why does this thing have a float LWCO and a probe LWCO?

and I’m afraid to ask, but why shut off a radiator that was near a drafty front door?

As to your first question about LWCO configuration… I don’t have any idea

As to your second question… I had this illogical (clearly) thinking that “It’s a waste to have the heat blasting in right next to a drafty door, and nobody really stands by the front door anyway” But after reading all the comments here about balancing the radiators throughout the house, I realized my thinking was wrong. I also added some weatherstripping to the doors, which seems to have substantiallly reduced the leakage.

Jamie Hall

ethicalpaul said:

Why does this thing have a float LWCO and a probe LWCO?

and I’m afraid to ask, but why shut off a radiator that was near a drafty front door?

Cedric has the same arrangement/ The float type (which does need to be blown down once in awhile so the float doesn't hang up) controls the automatic water feeder. The probe type is the backup -- on Cedric it is manual reset. Good arrangement, particularly as the two types fail, if and when they do, in quite different ways and for different reasons.

ethicalpaul

OK yeah it does provide a nice backup. I'm glad you turned that radiator back on, @rsilverst !