Carrier Chiller Help

hi all,

after putting my hand up in the office to go have a quick look at a site thats "having probs" thought would be same old same old kwen it was carrier and havnt done much on them so was up for a challenge when I got there I found a bloody chiller!!!! So from one A/C man to all you chiller man here’s what I found

They is one carrier 30RH-120B0110-PEE— outdoor
There are seventy one 42NF33SGLCB indoors (3.14kw cooling/3.93kw heating)
And the same number of cepl130394-01 room controllers

From what paper work ive found on site these room controllers will only work 6 types of indoors but doesn’t say which ones!! Any ideas? The water flow in is as low as half a bar when iam thinking it should be 2-3??? Am I right?? I’am told carrier commissioned the site so iam guessing its all be set up right, set points, pro-dialog plus ect any thoughts guys it over to you

last time i put my hand up to get me out of the cold

Thank paul

OK, so you walked into this one ;)

So what is 'the problem' do we know yet?

Saying the water flow is 0.5bar means nothing I'm afraid. Bar equals pressure not flow.

If you saying that the pressure drop across the evaporator is 0.5bar then that would make more sense but without the design pressure drop it still doesn't help too much.

Will dig around the Carrier site and see what we can find......

the client is saying that its been in for 18 months and has never worked right from day dot,when they have the same system in another hotel with different wall controllers and it works fine so i iam the fresh pair of eyes on the site,the pressure iam getting at is the main incoming water pressure is half a bar,means nothing to me but iam guessing due to the system is spreed over three floors and 71 indoors that was a little low to me but remember iam an A/C man

Quote:

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Originally Posted by superswill

the client is saying that its been in for 18 months and has never worked right from day dotman

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Hi superswill

But what is the problem your having?

No cooling, no heating, no airflow, no even temperature etc

Regards
Lrac

lrac

there saying the rooms never gets to temp,and i tend to agree as the air off is 7c on cooling and 24c on heating buts there have electric heaters

Hi superswill

Have you interegated the main carrier unit with the pro-logic to see what parameters have been set too.

It may be a simple case of cycling the condenser fans at a higher temp or changing the capacity control of the system.

carrier engineers always set the controllers up by the book but this is never the case, we look after 6 sites where we have had to make major adjustments to the pro-logics.

If your not sure of the capacity is correct simply turn off a number of indoor units and see if the chiller can reach a decent evaporating temperature + 7 air off is too high for your application, but dont forget anti freeze if you run lower evap temps at the chiller.

Please check the water outlet temp at the chiller and the return as the water may be warming as it circulates the building we had to gut 2 installations and re insulate as the initial tender stated a water outlet temp of + 8 when infact it needed + 1 C to work correctly, as always jobs like this are on price and + 1 is dearer than + 8 C.

Good look
Lrac

With an air off temp of 7C in cooling I don't see how you can say the chiller is at fault. Sounds like the unit is undersized for the room load if the room won't come down to temperature.

Have any room load calcs been carried out?

What are the chilled water circuit temps?

frank

yeah did a room calc and the units are ok from the size,think its mainly the indoor to room stat the customer wanted checking but having no joy finding any info on them and while on site came accross far to many locked doors to any proper checks water side