homeowner questions re steam....

Bill_neophytehomeowner

My first post here, and will probably spring for the book on steam etc., but 3 questions for you steam pros--

1) My wife & I bought a 1740's house in Connecticut about 10 years ago-our first. Had a newish Burnham boiler & works well -1 pipe system. 2 years ago, we added a 100 sq ft bump-out to kitchen & we moved the now "undersized" radiator to our bathroom. Our plumber moved the steam supply line in the new kitchen area about 3 feet. We installed a new radiator-all worked like a charm, until last week, when we had banging in the 2 year old kitchen radiator. I shut off the valve, and the banging stopped. I disconnected the rad & drained about a gallon of h20 and reconnected- it was still banging. ... So, I called for heat & disconnected the air (?) valve, and waited to see what would come out-steam or water-well it was about 3 gals of very hot water-into a bucket) them steam came through.. I reinstalled the valve & it now all works to perfection. the question-why was there 3 gals of water in the radiator- after 2 years of working perfectly?

2) radiator in upstair bedroom is WAY too hot. it's a small & well insulated BR. Is there a solution other than replacing the radiator with a smaller unit?

3) should I periodically drain & refill the water in the radiator-we have it serviced once a year. many thanks for any info.

jpf321

rad pitch, smaller vent and huh?

A) it would seem that it probably took 2yrs for the badly pitched rad to finally give you trouble .. the only reason there is water (and that much) remaining in a rad is because that water was unable to run downhill when it was supposed to (either b/c 1) you have a one-way check valve on the line to the rad or 2) you don't have your floor valve fully open or 3) the rad, or the pipe it's connected to, is pitched the wrong way)



to slow down the bedroom rad .. you can replace with a smaller rad .. but the easier option is to install a slower vent, or turn down an adjustable one if that's what's currently installed .. by slowing the escape of air from a rad, this limits the amount of steam that can enter .. by limiting the entry of steam, you are limiting the entry of heat ..



C) I think you meant to say boiler .. not radiator .. once a year would be fine...make steam immediately after refilling to eliminate any dissolved oxygen which causes rust.

Bill_neophytehomeowner

thanks for the info...

jpf321, thank you.

A )I can't see the pipe in question particularly well, as the crawlspace is more of a wriggle on your stomach in dirt-space. pitch is unknown-probably sagged over years... I will block up the rad so pitch is toward the floor valve (yes, fully open). Guess my question was also-was the water that came out of the radiator in the pipe and forced out by the steam? I assume the h20 was in a section of unproperly pitched pipe ?

I will get an adjustable vent for the "hot" radiator...

C) yes, i meant boiler water-just drain & refill to proper level in the sight glass? any reason not to do it in wintertime between steam firings...? Thanks for the info!

jpf321

generally..

C) generally, frequent water additions is discouraged because of the corrosion that i mentioned above due to the dissolved oxygen in new water .. old water that has been boiled once or many times is free of the dissolved oxygen that will eat away at guts of your boiler.



A) air vents are designed to close when they are met with water .. so the water had no escape until you removed the vent...certainly steam pressure had a hand in relieving the water...you may find that it now works again for another year or two, but fixing it is a better idea. water in that volume would have to had been hidden in several places .. pipe, rad, other places... see the linked pipe chart for how much water a single foot of a specific pipe holds (column 2nd from right)

Unknown

TRVs for Overheating

Hi- Get the steam books "We Got Steam Heat" and "The Lost Art of Steam Heating". Well worth while and will answer any questions you have. They also have the advantage that we can refer you to a certain page when you have a question.



In answer to your questions, jpf321 has covered them well. On your question #1- make sure the radiator vale is fully open. On a 1 pipe steam system the valve has to be fully open or fully closed.  Check the slope of the radiator and make sure it slopes slightly towards the steam pipe end so the condensate can drain back.

On your question #2- This seems an ideal situation to use a TRV.   I have TRVs on about 75 % of my radiators, mainly to stop overheating and also to shut off portions of the house in winter.  There are several models of  TRVs. You need the one for 1 pipe steam. It has a built in vacuum breaker that allows air back into the radiator at the end of a steam cycle.  I've attached an info sheet is on Danfoss TRVs and these are available from Pex Supply on the internet. You will want the model RA2000 1ps  ( SKU: 013G0140)  As the TRV goes between the radiator and the radiator vent you will also need a straight radiator vent.  (The one you are using now probably is a 90 degree angled vent.)

- Rod

nicholas bonham-carter

"newish boiler"+ excess radiator water [3 gal]

something must have changed in the system, in order to cause the radiator to collect so much water. in addition to those possibilities mentioned by my esteemed colleagues, j and rod; there could als be a clogged pigtail, which is causing the pressuretrol to allow the pressure to be too high. this could raise up the returns' water-level, and allow it to go places it should not. this is a situation where a good low-pressure gauge would be beneficial. remember that each ounce of steam pressure will raise the level in the returns 1.75 inches!-how many ounces do you have in your system?-nbc

Bill_neophytehomeowner

good info...

I have read all & it is much appreciated. Ordered the books...too much to learn by one question at a time approach. I will get the TRV valve. I am a steam heat fan, I have removed (how easy that sounds) several & taken them to be sandblasted & then I re-painted. They look like new. My back will never be the same, though.....

Unknown

Danfoss Info Sheets

Just noticed that on my previous post the attachment didn't go through. Here it is again plus some other info. Here is a link to the Danfoss website and some good animations which help explain the operation on the TRV.

http://na.heating.danfoss.com/Content/161a8b0f-a195-42b2-9487-7ee4083398cf_MNU17424439_SIT209.html

The animations are mostly for Hot Water TRVs but work the same principal on 1pipe steam on the air vent side. The valve in this case is especially designed for one pipe steam.

- Rod

Bill_neophytehomeowner

TRV

This is a huge help. When we purchased our home, some of the radiators had these, which I removed when we sandblasted the rads, not realizing exactly what they were. Think I saved some as they looked expensive. Guess we wanted massive heating at the time, and removed....whoops.

Bill_neophytehomeowner

TRV

This is a huge help. When we purchased our home, some of the radiators had these, which I removed when we sandblasted the rads, not realizing exactly what they were. Think I saved some as they looked expensive. Guess we wanted massive heating at the time, and removed....whoops.

Unknown

Macon OPSK TRV

Since you think you already might have some TRVs, I attached this as you may have this type rather than Danfoss.

The silver dome is the air vent and the little brass "barrel" is the vacuum breaker which lets air back into the radiator. On the Danfoss 1 pipe steam TRVs, the vacuum breaker is internal.

 - Rod

nicholas bonham-carter

drain and refill

why not just "blow down" the boiler, and returns occasionally, by opening the drain valve and letting out a few gallons of sediment. a full port ball valve helps here, as does a floor drain. the advantage would be less total new water added all of a sudden. note that "drain and refill" is not a substitute for skimming!!

we would like to see pics of your house! 1740's must be one of the older houses mentioned on the wall! can anyone remember an older one?--nbc