Gretz Pitot not heating

[jump4way]

I'm looking for a little help regarding my recent install of my gretz heated pitot. I installed it in my RV4 per the plans. The control box is mounted inside the wing near the pitot, and the optional LED light system is run to the panel. I am using a 10amp breaker switch at the main bus. When I switch on the master followed by switching on the pitot heat, I see two lights, red and orange. If I understand correctly, this indicates that the unit senses a low temerature environment and it's calling for heat. All seems to be working normally except the pitot does not even get slightly warm to the touch.

My questions are, what temperature does the unit ask for heat at? Current OAT is approximately 45 degrees farenheit.

Where would you start troubleshooting at this point?

Thanks in advance. Hopefully one day I have learned enough to be able to contribute more to these forums.

[rleffler]

Originally Posted by jump4way

I'm looking for a little help regarding my recent install of my gretz heated pitot. I installed it in my RV4 per the plans. The control box is mounted inside the wing near the pitot, and the optional LED light system is run to the panel. I am using a 10amp breaker switch at the main bus. When I switch on the master followed by switching on the pitot heat, I see two lights, red and orange. If I understand correctly, this indicates that the unit senses a low temerature environment and it's calling for heat. All seems to be working normally except the pitot does not even get slightly warm to the touch.

My questions are, what temperature does the unit ask for heat at? Current OAT is approximately 45 degrees farenheit.

Where would you start troubleshooting at this point?

Thanks in advance. Hopefully one day I have learned enough to be able to contribute more to these forums.

There are several troubleshooting steps to take.

1. Make sure that the thermistor isn't shorted to the pitot/ground. Using an ohm meter, test each lead. I have seen this a coouple times with the Gretz pitot.

2. Is the control board apply current to the heating element when the light is on?

3. Make sure you have the LED wires installed correctly.

I don't remember the exact temp, but it was slightly above freezing. I spent quite a bit of time testing the units (a long story that I won't go into here) playing with ice to cool and heat the pitot to validate that it worked as advertised. That's when I discovered my thermistor was shorted to ground. The gentleman in Australia that purchased the business from Warren, promptly replaced my unit.

btw, Vertical Power sells a board that allows you to intergrate the LED annuciators into just about any EFIS that can accept external inputs for annuciation.

bob

[jump4way]

Thanks for the great input. I have a GRT horizon I efis, I might look in to integrating the annunciation.

I went back and checked the wiring and figured out the problem. I had a loose ground wire. I guess it always pays to check the simple stuff first. I hate relearning this lesson but am glad that the problem was a simple fix.

Thanks again.

[rleffler]

Originally Posted by jump4way

Thanks for the great input. I have a GRT horizon I efis, I might look in to integrating the annunciation.

I would if you can. Those LEDs are rather tacky looking. The board VP sells converts the +5v to ground, which is what most of the EFIS inputs are looking for to actuate the annunciator. I don't recall the options for GRT. It's been too long since I've read those manuals.

bob