New thermostatic radiator valve on old radiator fitting?

Whatever you replace it with you will have to replace the spud and union fitting. A new valve will probabl last longer than a TRV. If a TRV goes bad it is usually the actuator and the valve is ok.

You have to position the actuator the way the mfg instructions show or use a remote sensor.

TRVS and radiator valves are not all the same dimensions so shop wisely.

Honeywell, Danfoss Tunstall associates sells Macon they are all about the same. Pick the one that fits physically the best.

This actuator: Honeywell T104B 1038

This valve: Honeywell V110E 1012

You can place the temperature sensor up to 6 feet away from the radiator. However, you will have an exposed capillary tube from the control the the actuator. and the short valve profile you want to use.

Yes, a delta P circ and a current sensing relay would allow the TRV to initiate a call for heat - if that radiator were the only one being fed from that circulator. But if not, then how would you regulate the heat in the rest of the house since the circulator would “see” the open pathway through the rest of the radiators and run continuously?

I experienced one customer where I installed TRVs on several radiators so the tenants would stop leaving the window open because of excessive heat and the fuel usage went from over 4000 gallons per year down to less than 2000 gallons per year.

Rooming house in Cape May NJ

• install four TRVs on the hottest rooms
• install thermostat in owner's apartment
• install remote sensor on owner's thermostat with the sensor in the coldest room

Result was to cut fuel usage from 4000 gallons to 2500 gallons

Next summer,

• install 7 more TRVs in the remainder of the building
• Install ∆P circulator

Reduce fuel usage to 1900 gallons per year

Net result: The coldest room is always open full, the thermostat will call for heat and keep that room comfy. All the other rooms and the owner's apartment will be adjustable to each individual's comfort. …and Very happy customer, + Unhappy fuel dealer = Had to buy dinner for the fuel dealer and his wife to tell them "at least they didn't switch to gas heat!"

That is all the owner of the rooming house in Cape May wanted. four new hand operated valves. I talked her into the TRV's for about $400.00 more. The labor to drain the system, replace the valves and fill and vent the system was the same for both jobs, and the result with the lower cost job would be to manually enter the tenants room and adjust the valve by hand and see how that worked, then back again a few hours later to see how that adjustment worked, then back the next day to see how the room temperature is doing now…. and on, and on, and on!

TRV = tell the tenant if the room gets too hot turn the dial to the left. If the room gets too cold turn the dial to the right. Let the tenant select the comfort level and the valve will do the work for you.

In the Cape May "coldest room" I played a psychology trick on that occupant. I placed the remote sensor behind a T8222D thermostat and let them adjust the thermostat as needed. The thermostat was not wired to anything. It just hid the remote sensor.

You have a point there, but do you want to have to access the room any time or should I say ALL the time. The point of the TRV is that it is automatic. So the labor to install a manual valve or a TRV is identical for you. the only cost difference is the price of the valve and actuator. I like the idea of the remote actuator with the 6 foot capillary tube where you have confined space for the valve to be installed.