yep, at 5.5Ω and a DC transformer @ 24V you are asking that transformer to provide 24/5.5=4.4A - when it can only give you 1A. You need a AC transformer. Give me a minute to figure out VAs.
Alright, 60VA in-rush (this is the instant current when turning on, but lasts for a brief moment) - and a 7VA when stabilized. The transformer I pointed to above should get you going. It’s actually overkill, let me see if there’s any 1A, but if that’s fine for you, go for it.
This will definitely work:
Make sure whatever you buy is 24V and outputs AC, not DC.
So if either one will work, should I get the over-kill one you found first? It is only a dollar more. And I will get AC - I didn’t realize I was getting a DC one earlier. Or does it truly not matter if I get the 40 vs 50 VA?
I removed the first one as it was DC - you need AC
If using DC voltage on an AC relay coil, you’re essentially overloading the coil - in the DC world, the current is voltage over resistance - you have a 24V and 5.5ohm requirement, so you’d need a staggering 4.5A - assuming you get a 24VDC@5A transformer, it will work but you’re now spending over 100W to drive a solenoid - the power dissipation or lack of thereof will make it melt and potentially catch on fire. We don’t want that, that relay was not designed for DC currents.
In the AC world, when the power turns on, the rush current will show up but as the electromagnetic field is formed in the coil, a new, inductive resistance appears, which, along with resistance, results in a higher impedance - current in AC is voltage over impedance, with impedance being much higher than the 5.5ohm resistance - this causes the current do immediately drop down to about 292mA (7VA used, at 24V means about 7/24=292mA). in-rush power is listed at 60VA (cca. 2.5A) and stable power at 7VA (cca 292mA). I believe Rachio reserves about 250mA for each of the max of three valves it can drive - this being over 250mA may explain why Rachio complained right away. Hope the explanation helps (confuse you more LOL)
between 40VA and 50VA (note in AC we don’t use W watts, we use VA volt-amps) - I would pick the 50 if the price diff is irrelevant - they both are over the stable 7VA, but it’s likely the 50VA will handle the in-rush split second 60VA power draw at start up easier than the 40VA. We don’t know their in-rush current ratings, but they both should be way over that 60VA. We’re talking about 20-50ms of in-rush currents, they can handle it.
Get the one that arrives faster? LOL
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Thank you so very much! The new transformer arrived tonight and I hooked it up - and we had water! I really appreciate your time and knowledge getting me on the right path! Have a wonderful weekend!
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WAIT, THAT ACTUALLY WORKED???! 
Glad I could help! Finally got to use my electronics license, though I am more of an embedded engineer 
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Thank you, Sir
y’all have a great weekend!
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@Cindy may I ask you for a favor please, if you purchased that initial transformer based on someone’s recommendation/link on the forum, maybe please let them know to link to an AC/AC transformer instead? May save others a great deal of time and effort, thank you 
I think I saw what they recommended and accidentally bought a different one with faster shipping - so it was my mistake.
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