Jacuzzi settings - regulating heat

[SnowHot]

In a thread about heat settings on hot tubs, I read that there were some benefits to using the economy settings when you're located in a hotter climate.
I took the initiative to read the manual for my spa and set the setting on economy (F5) figuring that it would help my utility bill and be fine for the summer months.  This has been fine on hotter days maintaining the 101º summer temperature that we like, and we don't mind the drop in temperature in the evening, but we've had a few cold nights recently and are finding that the temperature doesn't like to stay 101º even when the cover is on snug.  Sometimes it drops as low as 96º.

Yesterday we got caught in a thunder storm while we were out and came home really cold, thinking that the hot tub would feel really good, but the temp was 100º and dropped to 97º while were were in it. 
(Outside temp had been 100º earlier in the day but dropped to 79º after the thunder storm)
This has us concerned that may have a difficult time maintaining a higher temperature during the winter months.

A few facts:

• Spa Model - Jacuzzi J-335 (couple years old)
  
• We live on the NW edge of Reno (summer temps are usually 100º, winter temps usually in the 20º's-30º's)
• Spa location is on our patio with direct sun during 2 hrs of the day, mid day
• Evenings get pretty cool and breezy, even in summer.
• Our idea is to have a temp of 101 in the summer and 104 in the winter
• Set up with 50amp GFCI

Any help in settings or features that can help us regulate the heat a little better is much appreciated.

[goose973]

Not to sound like a jerk, but maybe try the standard filtration/circulation cycle instead of economy. I keep my Sundance on the standard setting and it stays within 2 degrees of set temp.

[SnowHot]

Goose, thank you for the candid response.
I'm willing and able to set the settings back to factory settings (F1), and actually considered doing that yesterday.

To be clear, the reason I set it on the economy settings was because of something I read on this site(can't find it now) about economy settings being better on the tub if you're in a hot climate.

There have also been threads on temperature settings hotter than 104, which interest me.  We don't want a temp hotter than 104, but it seems that there is some natural cooling of the water during use, and a higher temp may help in keeping a comfortable winter temp.

[goose973]

To give you an idea of my conditions so you can extrapolate to your situation, I'm in eastern PA, and our summers can be pretty hot. The upper 80's and 90's are the norm. My tub sits in almost full sun, but on F1 it is never below set temp (97) and very rarely higher than 99. I'd try F1 and see how it goes.

[SnowHot]

Thank you Goose973 for chiming in.

We've gone through a complete billing cycle with our utility company since setting the Jacuzzi on economy and see no significant impact on cost.
I reset to F1 this morning.

I'd still like to hear from someone knowledgeable about the effects on hot tubs in hot climates.
Does a hotter climate have any negative impact on heat pumps, and other such stuff?