hp trip

[han81]

hi all

new to forum, first post here. I am going to a job on friday to change a hp transducer on carrier chiller as it has an intermittent fault. Engineer that visited site previously also said system tripping on hp even though coil is clean and cond fan running at full capacity. not come across this before, any suggestions?

[Grizzly]

Welcome to the forum Han.
You seem to have answered the question yourself.
Basically the hp is monitored from within the chiller software.
Using the Hp transducer signal input.
Therefore if the transducer is as you say faulty.
It is reasonable to assume that the signal it supplies the chiller software is also faulty?
Therefore could not the pressure it reads be "High" causing an false high pressure fault?
Cheers Grizzly

[han81]

hi grizzly
thanks for the response to my post. Spoke to engineer who originally attended job and he is saying condenser coil is hot to the touch and that he applied a guage and found discharge pressure to be around 26 bar. I understand that there could be a false pressure reading on the digital display from the faulty transducer but would this actually effect the coil temp/pressure with the fan at full capacity. Is it possible the compressor is faulty aswell? Im on the job tomorrow so can investigate further myself.
han81

[acnerd]

hi grizzly
thanks for the response to my post. Spoke to engineer who originally attended job and he is saying condenser coil is hot to the touch and that he applied a guage and found discharge pressure to be around 26 bar. I understand that there could be a false pressure reading on the digital display from the faulty transducer but would this actually effect the coil temp/pressure with the fan at full capacity. Is it possible the compressor is faulty aswell? Im on the job tomorrow so can investigate further myself.
han81

Unless you are having hot weather in your area, 26 Bar is quite high. See for yourself if the condenser coil is clean. Otherwise you may have quite a heat load on the system, amongst many other reasons for high condensing temperatures. Take all your pressure/temperature readings, superheat, subcooling etc and make your own mind up.

I hate inheriting other people's jobs. Sometimes they misdiagnose a fault, and then you're stuck with explaining to the customer why it still isn't fixed. :(

[Grizzly]

hi grizzly
thanks for the response to my post. Spoke to engineer who originally attended job and he is saying condenser coil is hot to the touch and that he applied a guage and found discharge pressure to be around 26 bar. I understand that there could be a false pressure reading on the digital display from the faulty transducer but would this actually effect the coil temp/pressure with the fan at full capacity. Is it possible the compressor is faulty aswell? Im on the job tomorrow so can investigate further myself.
han81

Thanks for the update Han,
Armed with this further information.
I assume that you have 2 separate issues as implied!
To be able to comment further more information is needed.
26 bar does seem high, but that depends upon what refrigerant we are talking about?
Good Luck Grizzly!