What metrics determine whether a zone valve is a suitable replacement for another?

Question

I need to replace a leaking zone valve in my basement. I think I found a replacement for it off of SupplyHouse.com but wanted to make sure it really is a suitably replacement before I pull the trigger on $150. My current White Rogers zone valve:

And the replacement I think I've found for it is here.

My question:

My current zone valve says its rated for 24V and 0.4 amps, and the one on the site just says 25V but has no amperage rating. How can I tell whether this is a suitable replacement for my current zone valve, and (besides voltage and amps) are there any other metrics that determine compatibility (PSI, etc.)?

Answer 1

Let's see if I can answer in a way that steers clear of "shopping question!"

A valve has several parameters that you might want to compare when searching for a replacement. For example:

• Number of ports
• Port sizes
• Port connections (solder/sweat, pipe thread, gender, etc)
• Construction materials (operating temperature, pressure rating, suitability for potable water if applicable, fluid compatibility)
• Pressure drop at required flow level
• Operating voltage (and AC or DC)
• Current requirement

One presumes that when a system was designed certain valves were selected because they satisfied certain criteria of the design. The reality though, especially in a residential setting, is that often enough there was no formal system engineering or design work done. The components are chosen simply because it's what the installer had on hand at the shop or in the truck or it's simply what they always use.

The ideal is to choose a replacement that approximately matches whatever specs you can find on the old part but don't sweat it too much if you can't find an exact match.

For the given valve the obvious specs are that it's a 1" valve, appears to be sweated/soldered to the piping, is operated with 25 V AC (nominal), and draws about 0.4 A. For a residential probably-not-carefully-engineered system that's probably about all the detail we need for choosing a replacement.

The part you linked at SupplyHouse is a 3/4" valve but otherwise similar (24 V is close enough to 25 V, amperage is about the same, etc). They do list an 1311-103 part as well, which appears to be a direct match to the one you have now.