High Pressure Switches

[basprofessional]

I must ask someone’s opinion after being out of the refrigeration side of the business for a few years. I have a customer with several walk in freezers and coolers with automatic high pressure switches. When the head pressure gets too high the high pressure switch trips off and then automatically resets. The result is the units cycles on and off on high head pressure. Naturally, the high head pressure needs addressed. However, it seems to me the automatic switch seems like a bad idea. Does anyone agree with my thought?

[Phase Loss]

I like the auto reset switch. When set correctly, the customer should notice a problem with the cooler/freezer while the high pressure safety control is cycling on/off. At the same time, it gives them a little refrigeration.

I don't like the manual resets because once it trips...it creates an emergency call.

[barbar]

In the past I was very much in favour of manual rest high pressure switches, but as most system now have some level of electronics, (anti cycle, fault history) I have moved towards an auto-reset high pressure.
If auto reset and limited controls are used, make such you have a large diff to ensure short cycling does not occur.

[jpsmith1cm]

I use nothing but manual reset controls.

Yes, they create a lockout condition but, without that, sometimes, you'd never know that there was a problem.

[2sac]

Manual resets

[jackintheboxtec]

Manual resets

X2

[VTP99]

Manual reset for job security

[Six]

Any refrigeration tech here keep a list of defrost times for each customer? Place I used to work had the Exxon tiger mart gas stations as a customer.

The attendents would see a rise in cooler temp and call the answering service in the middle of the night usually aand we had to respond. Most of the time it was the reach in going into defrost. I made a journal that referenced defrost timer settings with store numbers.

Saved a few headaches.

[Six]

Oh and remove head pressure switch and replace with igniter control circuit to launch multiple salvos of roman candles.

[jpsmith1cm]

Any refrigeration tech here keep a list of defrost times for each customer? Place I used to work had the Exxon tiger mart gas stations as a customer.

The attendents would see a rise in cooler temp and call the answering service in the middle of the night usually aand we had to respond. Most of the time it was the reach in going into defrost. I made a journal that referenced defrost timer settings with store numbers.

Saved a few headaches.

With most common timers, that's kind of silly.

Power goes out for an hour and, unless you went and reset all of the timers to correct time of day, your notebook is useless.

What we do is instruct all customers to wait a half-hour to 45 minutes after finding a unit warm before calling.

[Six]

With most common timers, that's kind of silly.

Power goes out for an hour and, unless you went and reset all of the timers to correct time of day, your notebook is useless.

What we do is instruct all customers to wait a half-hour to 45 minutes after finding a unit warm before calling.

Timers were checked during PMs.

You can imagine we thought of telling the gas station attendents to wait. You might as well try and have a conversation with the Slurpee machine.

[basprofessional]

When the automatic switches were in place the customer would ignore the fluctuating temperatures. However, after installing the manual switches the customer wanted to address the high pressure problem.

[jpsmith1cm]

When the automatic switches were in place the customer would ignore the fluctuating temperatures. However, after installing the manual switches the customer wanted to address the high pressure problem.

BINGO!

Make 'em call you out.

Only way to get it done sometimes.