What TPMS limits do you set?

[dpinvidic]

I can't find any information on what limits I should set for Low/High alarms for pressure and temperature on my TPMS.

I don't want false alarms, but I do want to get an alarm as early as possible.
What is a good low pres. setting (inflation pres. -5lbs??)
The high temp default on my TST system is 70 deg "C" (158 F).

Thanks,
Dan

[Dr4Film]

Under-inflation is far more important than high pressure limits.

A tire is considered flat once it reaches 25% of Cold Inflation Pressure. Example: if your CIP is 100 psi, once the tire reaches a loss of 25 psi then you are basically driving on a flat tire and have permanently damaged the tire.

I would want to be warned well BEFORE it reaches that point. So a good setting would be about 12-13% below CIP or in my example, that would be 12-13 psi loss.

Now for high limits, tires properly inflated to CIP will heat up due to road travel and whether they are on the sun side or not. It is common for tires to increase maybe 15-20 psi. So a reasonable high limit would be 25-30 psi over your CIP.

Not sure if your master control limits use psi or percentages but you get the idea.

Dr4Film ----- Richard

[Sky_Boss]

Originally Posted by dpinvidic

I can't find any information on what limits I should set for Low/High alarms for pressure and temperature on my TPMS.

I don't want false alarms, but I do want to get an alarm as early as possible.
What is a good low pres. setting (inflation pres. -5lbs??)
The high temp default on my TST system is 70 deg "C" (158 F).

Thanks,
Dan

I run 5% below target PSI and 20% above target PSI. I am more concerned about under pressure than over pressure within reason. The 20% seems to have eliminated nuisance alarms as long as tire pressures have been properly set.

"Target PSI" is the pressure I should use based on wheel weight and ambient temps. I use a spreadsheet to make that calculation go easy and to makes sure I have proper weight and balance of the coach.

[Doug Sage]

I have an older Pressure Pro and it is not adjustable. It came with set limits for over and under inflation. The change in pressure on our motorhome due to road heating or cold mornings does not exceed these set limits. However our toad is a Suzuki Grand Vitara and I set the tire pressure at 28#. The problem is that a 10% change is only 2.8 pounds. A cold morning sets off the alarm. I would like to be able to set the toad alert at 20 - 22#.

[dpinvidic]

Thank You gentlemen...

Sounds like 10% low limit and 20% high limit is a good setting.
With additional searching, I found the FAQ from TST for my system, and they also recommend 10%/20% limits.

And thanks for the spreadsheet idea on inflation presures....that will make things easier.


Dan