I installed a pressure regulator recently in a client's house. It was on the water line feeding the older style radiator heater. I had moved the separate water heater for that (?!? - I didn't design the system) in order to facilitate the sewer clean out in the basement and noticed that the existing valve seemed to be inoperable.

The pressure up in the Berkeley hills is pretty strong for some reason (close to a gynormous tank up the hill, perhaps) and I gather too much pressure is not good for the radiator and of no use at any rate.

I forget the brand, it was a bell shaped thingy about 4 or 5 inches tall. Just goes in the middle of the line. About $50 - $60 bucks IIRC. Not sure how steady the delivered pressure is. Probably has an off and an on pressure but likely to be much more sensitive than what you have now.

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