Modify Air Con in Rental house to save money (1 Viewer)

[sandcruiser]

Hey all,
I'm cross-posting this to the electronics forum as I'm not sure where to put it, but hoping a mudder can help with my HVAC question:

we've got 4 mini-split AC units in a 3br house (1 for the common area). I plan to be renting the house out to short-term clients in the near future, and know that the average short-term client can be a real AC nightmare. Folks typically crank all 4 units to about 50 degrees, then leave sliding doors wide open so that they can hear the kids in the pool... and I pay $500 for the monthly electrical bill.

So what I'd like to do is limit the coldest setting. Right now the remote will scroll down to about 16* C. That's much colder than anyone should expect to be in a tropical vacation home. I feel that if people can only set the AC to 20*C (which is still 68* F and a damn sight colder than our 90+ ambient) that they'll be just as happy as if it were set lower.

So does anyone know of an "easy" way to limit the coldest setting? I've thought about maybe installing a discreet digital thermostat that can cut the compressor's power if/when the interior temperature of the room is below X (x=68, for instance), but I'm wondering if there is some other, equally good approach.

Thanks for ideas
Steve

 

[bigndn]

Why not a locking cover for the thermostats? Then you could set it at whatever temp YOU desire. Cheap and effective.

Thermostat Guards | prothermostats.com - programmable thermostats by Honeywell, White-Rodgers, Robertshaw, LuxPRO

or a tamper proof thermostat?

http://landlordstat.com/?gclid=COC1o-j0rqACFRwTswod-gs7aQ

 

[sandcruiser]

the thermostat that comes with the units is a hand-held remote control.

for many reasons, I'd prefer something wall-mounted, but haven't found such a thing (yet?)

I think that they go w/ the handheld remote because the units offer various features- dehumidifier, 'smart' mode, fan speed control, temp control, and vane position control. That's a lot to have on a wall-mount unit unless the unit is specific to the AC unit.

I think I'll try running the unit and just flipping the breaker on the compressor to see if that stops the fan indoors. Then I'll maybe contact the mfr to see if that is liable to break anything! because it seems like it could be the easiest solution... just shut the compressor down when it hits a low enough temperature inside.

 

[bigndn]

the thermostat that comes with the units is a hand-held remote control.

for many reasons, I'd prefer something wall-mounted, but haven't found such a thing (yet?)

I think that they go w/ the handheld remote because the units offer various features- dehumidifier, 'smart' mode, fan speed control, temp control, and vane position control. That's a lot to have on a wall-mount unit unless the unit is specific to the AC unit.

I think I'll try running the unit and just flipping the breaker on the compressor to see if that stops the fan indoors. Then I'll maybe contact the mfr to see if that is liable to break anything! because it seems like it could be the easiest solution... just shut the compressor down when it hits a low enough temperature inside.

Maybe I'm thinking too simply, but why not just take the remotes with you? Set it for a certain temp (72 degrees) and be done with it. Is that not possible?

 

[bigdaddy]

Without knowing the Brand/Model it's hard to say what you can do with the limits. Read the manual and see if there are any options.

Do you have the Brand/Model?

Another factor is to "Adjust" your price to reflect somewhere between the best and worst case scenarios ($200 normal bill, $500 High Bill, so split the difference at $350 and charge accordingly). and if you want to be nice after they leave if the bill is $200, give them a $100 credit on their next visit.....just a thought

 

[sandcruiser]

good thoughts, keep 'em coming

can't take the remotes, or that would force the AC to be always on or always off, which is no good.

adjusting pricing might be a solution, but I just got my January bill, the lag between usage and billing is long, and thus hard to make adjustments. not impossible, but not easy. besides: people get grumpy when you charge them for their excesses.

2 units are tempstar 9,000 btu mini splits
1 is a 12,000 btu tempstar (I think)
and the third is an 18,000 btu GAir

I'll look for model numbers, but not now. Just had a few beers on the beach for "sunset" that ended five hours later. Must eat.

 

[LukeZero]

We sell Mitsubishi and Fujitsu mini-splits. I have no specific knowledge of who makes for Tempstar or GAir. The Mitsubishi and Fujitsu both have a "low limit" that can be set. OR- since none of these units sense room temperature at the remote, set the temp to whatever you think is reasonable, and take the remote with you. If the tenant needs to change the temperature- they can ask for the remote.

 

[sandcruiser]

I'll try to take a look and see if there is a low-limit

taking the remote is a no-go because then the clients can't turn the air on/off when they leave or when they open up the doors to enjoy the breeze, and I end up spending much more on electricity.

that limit is the key- if it exists on these models

We sell Mitsubishi and Fujitsu mini-splits. I have no specific knowledge of who makes for Tempstar or GAir. The Mitsubishi and Fujitsu both have a "low limit" that can be set. OR- since none of these units sense room temperature at the remote, set the temp to whatever you think is reasonable, and take the remote with you. If the tenant needs to change the temperature- they can ask for the remote.

 

[D'Animal]

Why not have the renters pay the electric bill?

 

[sandcruiser]

weekly renters

Why not have the renters pay the electric bill?

 

[MoJ]

Install a fake thermostat on the wall. Set the real temp at a reasonable level and then take the remotes with you.

We did a similar trick with office employees. One person thinks they're too hot, adjusts the temp lower, before the hvac can react a second person thinks they're hot and turns it down further. In the end it gets set way too low. At first we tried installing locked covers. Everyone complained so we put a fake thermostat in the common area with the real one in the manager's office. Energy bills dropped significantly and no one ever bitched.

By the way, if you like, PM me some details on the rental. I'd love to go back to Tamarindo.

 

[Rambrush]

We are using the white rodgers brand t stats available through grainger. The state has mandated specific settings in there buildings. we program the high and low in and then lock it.
The person in that office/building can override for say a hour then it reverts back. It can be shut off but the settings can not be accessed.
Get rid of the remotes. pull the cover on the unit and take a look but you might only have 3-4 wires for a t stat control. green,red,yellow maybe white depending on how its set up.

 

[LukeZero]

We are using the white rodgers brand t stats available through grainger. The state has mandated specific settings in there buildings. we program the high and low in and then lock it.
The person in that office/building can override for say a hour then it reverts back. It can be shut off but the settings can not be accessed.
Get rid of the remotes. pull the cover on the unit and take a look but you might only have 3-4 wires for a t stat control. green,red,yellow maybe white depending on how its set up.

Be really cautious with this. Very few mini-splits have the capacity to run an external analog, hard wired thermostat. Nearly all (all the ones I'm familiar with ) either offer no provision for external thermostat , or an add-on kit for it and then run digital controls. Not your conventional 4 wire system. (5 for a heat pump.)

 

[sandcruiser]

I've looked around a bit and seen nothing to imply that I can run an external tstat.

Mini splits are great, but not so much in this capacity.

taking the remotes is just not possible. 1) we get power blips at least once/week and that can turn off the unit completely. No remote means that a tenant would need a ladder to turn it back on. No good.
2) I don't want them running the AC 24/7, especially when doors are all wide open to enjoy the outdoors.
3) It just isn't done. Sounds silly, but true. People renting here expect to control their own AC.

Looks like we are courting long-term renters now anyway... so they will pay their own electric bill, and I can forget about all of this (until we get short term renters some future day, anyway).

Thanks to all for your responses!

 

[Rambrush]

Whoops I missed the mini split part.. Yes those are a different animal. Like posted the ones in my area are all remote controlled.

Be really cautious with this. Very few mini-splits have the capacity to run an external analog, hard wired thermostat. Nearly all (all the ones I'm familiar with ) either offer no provision for external thermostat , or an add-on kit for it and then run digital controls. Not your conventional 4 wire system. (5 for a heat pump.)