Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Balancing after insulation install

Hi Fellow Steamers,

So I just had some insulation professionally installed in my attic, with a $500 tax credit from the Fed and a 10% rebate from the State it made sense to do it.

I have a one-pipe steam system heating 1200 sqft. The boiler is way oversized so I am using a lot of venting to keep the monster on for as little as possible. I don't have the budget right now to replace it and the near-boiler piping.

I have two 30ft 2inch mains that due to a combination of knuckleheads and height restrictions are each vented by two Gorton #1s and a Hoffman #76 (with vacuum tab removed).

Before the insulation the bedrooms would be the coldest rooms in the house, so they use Gorton #5 and #6.

After the insulation the bedrooms are now +2 to +5 degrees on the rest of the house.

The room with the thermostat has a Hoffman 1A set as low as it will go.

My question (finally) is how should I re-balance the venting so we don't get a sauna upstairs. My goal is to try and keep the boiler on for as little as possible. Should I adjust the 1A next to the thermostat so it cuts out sooner and then increase venting on the downstairs radiators? Is there some other solution I'm not considering?




  • David Nadle
    David Nadle Member Posts: 624

    Have a look at TRVs. Danfoss has an RA2000 series with a one-pipe steam adapter. It replaces the existing vent and supports a thermostatic actuator to shut off the radiator when the room is at your desired temperature. You can purchase Gorton #5's or #6's in straight (not 90°) form and use them with the TRV adapters to get the venting you're used to without the overheating. I would put one in each bedroom. 
  • ChrisJ
    ChrisJ Member Posts: 15,441
    edited December 2011

    TRVs are only going to make his oversized boiler more of an issue in my opinion. 

    Personally, I'd turn that 1A up more and more until the rooms are comfortable.  How is the rest of the house? 

    Turning the 1A in the t-stat room up is a free experiment.  If other rooms end up too cool I'd then increase the venting on those as well. 

    If for some reason no matter what you do those insulated rooms are too stinkin hot you may have to finally go to TRVs.  This is where I'm at now with my livingroom and one bedroom.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • Rod
    Rod Posts: 2,067

    I agree with David. TRVs are the way to go. It isn't just balance you are looking for, it is being able to adjust the temperature in the individual rooms. I use them in my upstairs bedrooms as I like to sleep in a colder room. In those rooms I turn the temp way down at night into the fifties and then raise it during the day.  You could of course accomplish the same thing by using a setback on the main thermostat though my feeling is that this would use more fuel. The way I have it now I can get up in a cold bedroom, walk into a warm bathroom and then go downstairs into a warm kitchen. The TRVs also have the advantage in that you can shut down rooms in the house you don't use as often such as guest bedrooms which I believe saves fuel. I turn the TRVs in these rooms to the minimum setting of about 42 degrees and also place a rolled up towel across the door bottom to seal off the shut down room. I've attached a couple of info sheets on the Danfoss One Pipe Steam TRVs.

    - Rod
This discussion has been closed.