Harvest Right Troubleshooting – Condensor

I copy and pasted this here for easy access. The harvest right troubleshooting manual is the first place to always start! This information is supplemental.

Chris Webber ” HVAC Specs – Most important thing is that the freon is R 410a

Order of operations:

Remove the panels from the freeze dryer by following this tutorial video if needed:

How to Remove Panels (This video is for a Relay Board Replacement, but just watch the panel removal tutorial part)
https://youtu.be/gqgkP1kQ8Fc

We first want to see if the condenser is starting up and staying on. You can test this by turning on the freeze dryer, going to the test screen, and clicking the ‘freeze’ button to turn on the condenser. If you have a version 5 software, you can get to the test screen by clicking the leaf in the upper left corner on the home screen. If you have a version 4 software, you’ll need to click the customize button and then click the test button to get to the test screen. The test screen will say “functional testing.”

Check to see if the condenser turns on when you click the ‘freeze’ button. If it doesn’t turn on, you will want to focus your efforts on the starting coil, pictured below.

If the condenser turns on, but then turns off within 30 minutes, you will want to look at the starter coil as well as the other coil that keeps the condenser running.

After letting the condenser run for 30 minutes, use a gauge to check the readings on the starter coil to see if everything is working correctly. There are two places to check these readings, a high side and a low side. The high side shouldn’t go higher than 250 or lower than 220. The low side should read between 0-4 pounds. The low side is on the left. These readings should be taken while the condenser is running and after it has been going about 30 minutes. The high side is circled in green and the low side is circled in blue in the picture below.

Another thing to check for is to make sure the piece circled in the picture below is soldered. If it isn’t, it will need to be soldered. This may fix the problem.

If all of this checks out good, we will next want to observe the freon levels to see if anything is over or undercharged. If the freon is off, there may be a leak in the system. These leaks are usually on the Schrader valve pictured below, or in one of the U tube condenser coils.

Freon/Leak Testing Specs:

Our machine comes in three sizes:
Large – 5 tray
Medium- 4 tray
Small- 3 tray

The Large machine takes 7.5oz of R 410a
The Medium machine takes 6oz of R 410a
The Small machine takes 4oz of R 410a

The system itself is a very basic capillary tube system with no cold control, The condenser runs nonstop until turned off by the operator. There are no braze connections on the evaporator under the blown foam insulation and common leaks are found at the process tube off of the compressor and crotch on the filter dryer.

Determine if the system is still under positive pressure (If so then the filter dryer will not need to be replaced)

Remove the insulation tape from suction side of piping.
Use dry nitrogen and raise system pressure above 200psi.
Using soapy water test each braze joint for bubbling
Locate and re-blaze any leaking joints. After all leaks are located and brazed, remove nitrogen charge and vacuum the system down to 500
microns minimum. Recharge the system using the R 410a based off the sizes listed above.

Other helpful info from Pat:

Operating temperature, pressure, and amperage:

With a room temp of 70 deg
When the unit is properly charged with R410A
The bottom center of the chamber temp will be approximately – 40 to -50 deg
The suction pressure will be between 5 & 2 PSI
The high side pressure will be between 225 & 250 psi
There will be frost on the suction line where it leaves the foam up to the suction access port

Will Barlow

(800) 700-5508
95 Foxboro Dr. Suite #100
North Salt Lake City, UT 84054″