Need help buying TRV

David Nadle

Glad to hear

Chris, glad it works well for you. One more piece of advice, don't change too many things too fast. Change one thing at a time and observe for a while (at least a day). Otherwise you won't be able to discern what helps and what doesn't.

ChrisJ

Tweaking

After sleeping in a room that was between 65 and 68F last night while the rest of the house was 70F I've never been happier.   Before the TRV the room would have been in the mid 70s and I wouldn't be asleep.



Right now the first floor is approx 71F, system just shut off after a long run and practically every radiator is fully heated.  My bedroom radiator only has 4 out of 19 sections heated and the room is 68F.  Our second bedroom didn't heat at all, room is currently 70F which is approx the set temp on the TRV. 



Even my wife who hates spending any money agrees the TRVs at over $100 each were well worth the money and that even amazes me.



I'm trying to recall what Dan said in I think Greening Steam.  Every 3 degrees you overheat a space means a 10% increase in fuel consumption?  Those two bedrooms were overheating by 5 to 10 degrees at times, that means a significant waste in fuel to make people uncomfortable. 



I think the only thing that makes me wonder about the Danfoss TRVs is mine act much different than they claim they should.  For example around 1.25 = 68F while the scale they supply suggests that #1 is 55F and #2 is 63F.   I guess the location has a lot to do with it as well as tolerances in manufacturing.  Probably why there is just numbers on it and not actual temperatures.

ChrisJ

Update

Still fine tuning and tweaking but right now, assuming the system will behave the same in warmer weather its about as good as it gets.



I've slowed a few radiators up, got a #4 in my bedroom on the TRV which has given really steady and controlled heat from the TRV.  Only concern is what its going to do in warmer weather.  a #5 was too fast and a #6 was way too fast.  Both caused what I'd call hunting as it kept overheating and then skipping cycles causing the room to cool too much which in return caused one super hot cycle. I suppose, I could drill and tap the pipe or its elbow and vent it with a #6 to get the steam up there quick but leave the #4 on the TRV.  The thought has crossed my mind a few times.



I'm surprised that somehow the Gorton #5 has become the vent of choie in many rooms in my house.

ChrisJ

More refining

Over time I realized I wasn't getting steam up to my one radiator fast enough due to the #4 vent on it.  However, if I used a #5 it caused it to heat way too much before the TRV could react.  90% of the time the Gorton 4 + trv worked great.  But on cold windy nights it was causing problems as well as on very mild days.



My solution was to vent the pipe with a Gorton #6 and so far its been great. My other radiator + TRV does fine with a #5 or a #6 on it, doesn't seem to care so I left a 6 on it.