Opposite effect from what i expected

puff_puff_hiss

I've worked all the bugs out of my 1 pipe system over the last few weeks thanks to all the help but i couldnt leave well enough alone. The radiator in the recroom where the thermostat is was getting warm just a little bit too slow compared to the radiators upstairs and the upstairs of the house was getting too warm as a result.



Rather than change all the vents upstairs to slow them all down more, i thought i could just increase the venting on the recroom radiator and make it so it satisfied the thermostat sooner. I switched out the maid o mist 4 with a maid o mist 6 which is apparently 8 times the venting capacity of a 4.



Strange thing is that the recroom radiator slowed down even more with the 6 and upstairs got even hotter. I confirmed the vent size wasnt mislabeled since the vent port was definitely bigger. The vent still worked because the radiator got warm, it just took a while to get warm enough to satisfy the thermostat while the upstairs was cooking.



Any thoughts? I put the 4 back in and system went back to good enough. Do i assume there was something wrong with the 6 i bought and try again or could something else i havent thought of be causing this.



Thanks for any ideas!

BobC

Experimentation

If the boiler EDR and the radiator EDR are close you might have to cut down the venting on the other radiators so more steam will go to this one. In any case it would be a bit of a crapshoot to get the balance you want without a lot of experimentation. Perhaps a few TRV's would get you the balance you want.



Bob

Paul48

Is

that radiator at the end of the main that feeds the upstairs?

puff_puff_hiss

No, not on the end of a main

No. Its actually on a different main than what heats the majority of the upstairs.

Paul48

More

venting on that main?

nicholas bonham-carter

Venting speeds

Slow all the radiators down, with Hoffman 40's (the old standby), while at the same time putting more venting on the mains. This is especially true if you use any sort of setback or if your climate has wild fluctuations in temperature.

This arrangement fills the mains with steam completely before any steam begins to rise to the radiators. As a result the steam will start to flow into all the radiators at the same time. If you have followed the unfortunately wrong advice from the gorton website, you will have steam going into one radiator before another, and when you mix that imbalance with a setback-discomfort.--NBC

Hap_Hazzard

Where does the radiator heat up first?

There was a recent thread where someone said they had a radiator that seemed to be heating up at the vent end first. Steamhead suggested that this could happen if the vent was too fast because the steam can shoot right across the bottom and close the vent before the air has time to escape. With a slower vent, the steam is allowed to rise up each column as it advances towards the vent, so the side of the radiator towards the valve should be warm before the vent closes. If your vent is closing while the radiator is still cold, try a slower vent. Maybe a #5.

ChrisJ

Problems

I too have to be very careful how I change venting.

I have a 29' main and a 11' main, the 11' main comes off of the header first and if vented too fast steals all of the steam for a bit.



I currently have four Gorton 1's on the 29' main and a Hoffman 4A on the 11' main though I'm tempted to try a single Gorton 1 on it again.



I'm currently switching all of my Hoffman 1As out for Gortons and am very nervous in doing so as I could end up with a cold radiator or 2 if I do it wrong.



Why your radiator is behaving differently with a larger vent I cannot explain, other than if it suddenly has been colder there, maybe the radiators behavior hasent changed. Simply the ones that were hotter before, are still stealing more steam and changing the cooler rad to a larger vent made no change at all.



My system barely has enough steam to go around and if I vent a rad too quick I can increase the venting on another rad all I want and it will never get steam. I'm swapping in two Gorton C's on two rads upstairs that have always run too cool and I'm preying I get the effect I want.