Community Forums

411jeff · 07-24-2014, 01:16 PM

Is it normal for the A/C units to take 2 to 3 minutes to turn on?
Shore power or Generator same delay. If I set it to Fan Only, it turns on right away. It works, but I was wondering if this is a normal delay time.
I have a '98 Monaco Dynasty.

Thanks

Sky_Boss · 07-24-2014, 01:19 PM

Quote:

Originally Posted by 411jeff

Is it normal for the A/C units to take 2 to 3 minutes to turn on?
Shore power or Generator same delay. If I set it to Fan Only, it turns on right away. It works, but I was wondering if this is a normal delay time.
I have a '98 Monaco Dynasty.

Thanks

That seems excessive. I'd have to look at my manuals but I think we are somewhere around 30 seconds. Maybe a tad more.

bruceisla · 07-24-2014, 01:20 PM

Quote:

Originally Posted by 411jeff

Is it normal for the A/C units to take 2 to 3 minutes to turn on?
Shore power or Generator same delay. If I set it to Fan Only, it turns on right away. It works, but I was wondering if this is a normal delay time.
I have a '98 Monaco Dynasty.

Thanks

My 97 HR Endeavor with 2 Dometic A/Cs takes 2 minutes before the compressors start.

jesilvas · 07-24-2014, 01:52 PM

Correct. The fans will come on no matter what. But, sounds like you have the fan set on auto, which means fan won't come on until compressor does. Compressor's have delays to protect them from pressure loads.

Now, you didn't say what t-stat and A/Cs you have, so they are all different, so this is a general answer.

TQ60 · 07-24-2014, 01:53 PM

Normal...

The delay is to insure no short cycling of compressors.

bdickson · 07-24-2014, 02:02 PM

I agree, 2 minute delay is normal.

Dr4Film · 07-24-2014, 02:08 PM

I have Dometic Penguin Low-Profile A/C Heat Pump units. One 15,000 BTU and one 13,500 BTU. The front 15,000 BTU unit has about a 15 -20 second delay once I hear the fan first followed by the compressor starting up. The 13,500 BTU unit in the rear has an even shorter delay in that the fan and compressor are almost instantaneous.

2 minutes would be excessive in my estimation BUT it may be the brand of unit too.

I can only speak for what I have and have been accustomed to.

Dr4Film ----- Richard

wa8yxm · 07-24-2014, 02:17 PM

The instruction book says to wait 3 minutes betwen OFF and ON, the other way around you can do instantly but wait 3 minutes between OFF and ON, I'd say 2 is the manufacturer's compromise between those who read the fine manual and those who ASSUME to let it bleed off the head pressure.

On edit: That book is several GENERIC books on air conditioning, not necessarly the book for your unit.

YC1 · 07-24-2014, 02:20 PM

Mine too take forever to come on sometimes. Always been that way. Thought I had something broken several times.

Twomed · 07-24-2014, 02:27 PM

Never actually timed mine but Dometic says 2-3 minutes. Hotter it is the longer it seems, but I'm sure it's always about the same.

Several things figure in to time differences...the way the coach builder wired it, other installed options that may also have time delays built in. The build version of your Aladdin if a Monaco.

gruelens · 07-24-2014, 02:34 PM

My units have a 4 minute delay ......... at first it seemed unusual compared to the old style a/c units.

Pepper2 · 07-24-2014, 02:36 PM

On occasion mine takes a couple minutes, but most often it starts within 30 seconds.

PyrateSilly · 07-24-2014, 03:37 PM

30 to 45 seconds I think is what the front one takes to come on. The back on takes 15 seconds or so to come on. It's been that way for the last 3 yrs since we bought the coach.

NeilV · 07-25-2014, 05:47 AM

It depends on the unit. Some have a 15 second delay from initial start while others have no delay from initial start. Some have a time delay relay that on shutdown will prevent a restart for 2 to 3 minutes after they were shutdown to allow pressure to equalize in the system so you are not trying to start a loaded compressor. Some system may have a pressure switch that instead of using an arbitrary timer actually reads the pressure at the head and won't allow it to start until it drops to an allowable level so if the pressure is already below that safe level then the compressor will start with no delays. Now with a sequenced start setup on a load management system there can be another delay that will not allow multiple AC units to start at the same time to prevent multiple starting loads to be put on your electrical system but that is up to the coach builder on a rooftop system but should be the default with basement air system. With basement air the start-up sequence is usually 1 - Outside fan has to be started and verified running which allows Compressor #1 to go through its start cycle and once it has equalized then if the difference between the set temp on the thermostat and the room temperature is greater than 2 degrees compressor #2 goes through its start-up sequence. If you shut down a basement air system and immediately turn it back on you will have to wait for its shutdown timer to be satisfied before it will turn back on. Now turning the systems off at the breaker or a power failure that only lasts a moment can defeat the shutdown timer and allow either system to try and start immediately which also may be what some are noting.