Manifold gauge question.

[mattm]

Does anyone sell a refrigeration gauge with a peak needle incorporated in it ? My reasoning is that I have a RTU that the head pressure switch is randomly tripping. It may run a few hours or a few days. There's no ryme nor reason and instead of sitting there on the roof watching my gauges to rule out the pressure switch I would like to just hook them up and walk away and check later after it has tripped.

[cjett]

The only ones I know of are the digital gauges like the Yellow Jackets or Testo. They will show min/max readings.

[mattm]

I kind of thought that since I've never seen one in analog. If anyone knows of one please let me know........... or I could use this as an excuse to spend some money.. :D

[DeltaT]

http://www.dicksondata.com/info/home.php

You might be better off spending the money buying a min/max amp recorder for the condensor fan because the HP tripping is a symptom of something bigger such as the fan overheating and stopping.

Dickson (above) makes all kinds of recording devices. Some good buys are found on EBay. Cooper, Supco and a few other companies make some nice recording device too.

[mattm]

I've got a Supco recorder. Maybe I'll hook it up and see what happens. I just want to confirm that it's high head and not a faulty hp switch. It's on a Mammoth unit and the switch looks like it's original. Probably 25 - 30 years old. Also to add these don't have condensor fan motors per say. They run off a pulley and belt via the compressor.

[bustawrench1]

It's on a Mammoth unit and the switch looks like it's original. Probably 25 - 30 years old. Also to add these don't have condensor fan motors per say. They run off a pulley and belt via the compressor.

The compressors have a drive pulley on the front?? Like a car engine??

Or open drive with a belt system driven off the same motor??

I've seen countless Mammoth units with belt driven Cond Fans, but never driven off the compressor.

[mattm]

I'll have to take a cruise out there and take a look. These are at another property where I was helping the maintenance guy out.

[Advanced Response]

Matt,

I take it that you want a peak reading of the high side to see if the head pressure swith is doing its job or to see if you have a weak pressure switch?

If that is the case why not get a cheap automatic pressure switch (close on rise-rated at current pressure switch rating) and hook one side up to the low voltage hot(r) terminal and use a .5-1 amp fuse with the other side low voltage common if the fuse blows, you know the pressure switch is doing its job.. I have done this in the past and it works great.. Found some manual switchs doing their job and many that were not..

Just a thought..
J

[Phase Loss]

if this is an ongoing problem, i would replace the pressure switch. keep it simple :D

[mattm]

I'll give it a try. Thanks.

Also the condensor fans are belt driven from there own motors.



Matt,

I take it that you want a peak reading of the high side to see if the head pressure swith is doing its job or to see if you have a weak pressure switch?

If that is the case why not get a cheap automatic pressure switch (close on rise-rated at current pressure switch rating) and hook one side up to the low voltage hot(r) terminal and use a .5-1 amp fuse with the other side low voltage common if the fuse blows, you know the pressure switch is doing its job.. I have done this in the past and it works great.. Found some manual switchs doing their job and many that were not..

Just a thought..
J