Honeywell coolmaster recharge

[autochill]

Hi. I have two Honeywell Coolmaster air con units which had pipe damage. I have brazed up the pipes and they are ready to be recharged. They are set to run on R22. Any tips on how to go about it. (I have had them on a deep vacuum for 90 minutes each)

[Brian_UK]

Charge them to superheat and/or subcooling.

[autochill]

Thanks for the reply, I have charged the one with the specified weight through the single connector. It took the charge but is not chilling down, any clues?

[Brian_UK]

Depends on has happened to the unit when it was running with holes in the pipes; could be rotten oil and gunge stuck somewhere in the system.

Might be worthwhile degassing it and fitting another pressure tapping so that you can see what's happening.

[autochill]

As I mainly do cars can I just check I re-charged correctly. The BOC R22 gas bottle was valve up. I have also now charged the second unit and that is not chilling down either. The compressor is running and the low pressure line is getting hot on both units. Now I am really confused. Cheers. Mike

[Brian_UK]

Sorry, should have asked earlier as I don't know these units....

Are the heat pumps? if they are then it could be a problem with the reversing valves or controls.

[autochill]

They are not heat pumps they have heating elements in the blower housing to provide heat.

[slingblade]

This could be a number of things. a suction pressure and selection of air on/off temps would help for starters.

[Andy]

They are not heat pumps they have heating elements in the blower housing to provide heat.

Pressures and temperatures

Suction Pressure (discharge if you can) converted to saturated temperature.

Suction temperature at the indoor unit

liquid temp off the condenser

and compressor discharge pipe temp

Kind Regards Andy

[autochill]

When the machine is not running the gauge reads 3.5 bar on turning the machine on it goes into vacuum. Not sure if this gives you any better ideas.

[jamcool]

Sure the leak was fixed ,also check for any restrictions What was the charge weight that u say was put in?

[Brian_UK]

Auto, which pipes were damaged and required brazing ?

The fact that the compressor is pulling a vacuum could be a good thing, at least you know that they are pumping!!!

The suction line is getting warm because there isn't any cooling gas running through it; you have a blockage somewhere or a valve closed.

[autochill]

The high pressure line from the condensor was damaged. I was starting to suspect that the info. given by the owner may be a bit suspect. He claims they have been working but ( as they all seem to say) it just needs re-gasing. The charge put in one was 60g in the other 50g. I think he may have moved them and then not reconnected them up properly. Which valves may be closed do you think as I can't see any?

[Brian_UK]

I'm sorry I thought you were talking about air conditioning units but judging by the charge that you have put in, 60g and 50g, they must be something an awful lot smaller.

Even a domestic fridge will take more than that.

What exactly are these units please Auto.

[autochill]

They are Hoeywell HCL-140E free standing aircon units with an exterior condensor. Sorry just checked what I typed it was 500g on one and 600g on the other not 50 and 60.

[Ian Neill]

Hi looks like you are short on gas....whats the high side (discharge) pressure like? Is the pipe run overly long if so the you'll need more refrigerant.

[autochill]

Thanks for your help. the problem turned out to be that the units had been used in a brick works and because of the damaged pipes the evaporater was blocked with dust after flushing and re-charging they both worked fine. Cheers. Auto.

[Brian_UK]

Hi Auto,

Thanks for coming back with your results, it's always good to hear that a problem has been resolved and we appreciate your good manners in letting us know.