PDA

View Full Version : Mitsi split freezing HP pipe



Bat
07-05-2008, 11:59 PM
Hi,
Right I'm going to poke my head above the trench and see what happens!:eek:
I fitted a SRK40HD about 2-3 years ago. All has worked fine until this week :mad:
When in cooling mode the HP pipe freezes up until the system shuts down. I've took all the covers off the outdoor unit to find the pipe only freezes up after an electrically controlled valve, so I figure that's the problem. It seems to work ok in heating mode.
There's only a pipe in and a pipe out on this valve, but it has 4 or 5 wires (getting dark outside)
So to the questions...
Is this the electronic expansion valve?
Is there a way to test it?
Can it be freed off or fixed without replacing it?
If not who could fit me a new one, I don't want to be brazing that together!
Cheers,
Gavin :)

The Viking
08-05-2008, 12:31 AM
HP pipe??

Are we talking about the smaller of the 2 pipes to the indoor unit?

Yes, that valve is most likely the expansion valve but it's not a common failure point.

Have you checked the airflows and subcooling/superheat?

superswill
08-05-2008, 12:34 AM
Hi,
Right I'm going to poke my head above the trench and see what happens!:eek:
I fitted a SRK40HD about 2-3 years ago. All has worked fine until this week :mad:
When in cooling mode the HP pipe freezes up until the system shuts down. I've took all the covers off the outdoor unit to find the pipe only freezes up after an electrically controlled valve, so I figure that's the problem. It seems to work ok in heating mode.
There's only a pipe in and a pipe out on this valve, but it has 4 or 5 wires (getting dark outside)
So to the questions...
Is this the electronic expansion valve?
Is there a way to test it?
Can it be freed off or fixed without replacing it?
If not who could fit me a new one, I don't want to be brazing that together!
Cheers,
Gavin :)


i think misti call it an LEV,as the viking said abit more info and we will try to help

Bat
08-05-2008, 12:36 AM
Hi,
Yes small pipe sorry :O
It's only got a port on the suction side, so I can't :(
Air flow fine no piles of leaves or blocked filters....
Cheers,
Gavin :)

nike123
08-05-2008, 07:20 AM
Recover refrigerant and measure his weight. If weight is correct, check sensors at outdoor unit.

Also, check this troubleshooting of LEV after you checked above mentioned.
http://www.mediafire.com/?r7jrjxc5zzz

frank
08-05-2008, 09:44 PM
Based on the information so far, this seems to be a split unit fitted by a non refrig engineer.

Best guess is that it has slowly lost part of it's original charge (factory weight?) over the past 2 years and is now short of gas, hence the frosting after the EEV (LEV)

Nike's recommendation to recover and weigh the charge is spot on and the first place to look.

But, I doubt that our poster has the equipment to do this

Bat
09-05-2008, 07:36 PM
Based on the information so far, this seems to be a split unit fitted by a non refrig engineer.

Best guess is that it has slowly lost part of it's original charge (factory weight?) over the past 2 years and is now short of gas, hence the frosting after the EEV (LEV)

Nike's recommendation to recover and weigh the charge is spot on and the first place to look.

But, I doubt that our poster has the equipment to do this

Hi,
I spoke to a friend (commercial engineer, huge stuff) and he said the same.
I guess I'll have to find an empty recovery cylinder as mine has 134 in at the moment having been empty for months :(
I'm used to systems with TXV bolted on the evap coil :O
Cheers,
Gavin :)

sinewave
12-05-2008, 08:21 PM
Agree, check charge first, however I've had three faulty LEV's on Misti Elec's in the last 6 months albiet VRF units so it can't be ruled out. :(

Greengrocer
13-05-2008, 12:01 AM
Hi,
Right I'm going to poke my head above the trench and see what happens!:eek:
I fitted a SRK40HD about 2-3 years ago. All has worked fine until this week :mad:
When in cooling mode the HP pipe freezes up until the system shuts down. I've took all the covers off the outdoor unit to find the pipe only freezes up after an electrically controlled valve, so I figure that's the problem. It seems to work ok in heating mode.
There's only a pipe in and a pipe out on this valve, but it has 4 or 5 wires (getting dark outside)
So to the questions...
Is this the electronic expansion valve?
Is there a way to test it?
Can it be freed off or fixed without replacing it?
If not who could fit me a new one, I don't want to be brazing that together!
Cheers,
Gavin :)

The SRK40 HD fixed speed model was not fitted with HP control for all year round cooling. Min ambient for cooling was approx. 21c. What's the application? Many people who fitted these systems in comms rooms got caught out. I believe the latest models do now have HP control as standard (still only £248 nett trade for 4kW split). Cheap is sometimes not always cheerfull.