York Yk

[CaptJackSparrow]

I have a couple of questions I need help with.

1. I have a building that is 20 storys tall, chillers in basment. I want to remove an existing DK and install a used YK. The 19DK has 150 lb water boxs and piping but the pressure in the basment is at about 170 lbs. What is the ruleing on exceding the 150 lb rating. If I drop the YK in and by a freak accident the water box blows could I be liable? Is it against code? Are the existing machines against code? I have adusted the make up in the penthouse to 10psi to keep the pressure at 170 in the basement.

2. The 19DK is 400 ton. I need to look again but I think the design delta T is 14 deg and the chiller is a three pass. Chill water pump is I belive around 650 to 700 GPM. The YK is two pass 10 deg. What are your thoughts on droping in two pass to replace the three pass? Just trying to think through the problems I might encounter before hand. The York is a 52 in 42 out at 960 gpm.

Whatcha think?

[york56]

Im not an engineer but I know of a building that is 54 storys tall there are 6 large YK Chillers on the 12th floor mechanical room and all those Chillers have 300 psig water boxes on them , as for liability on your part mabey somebody else can help you out with that problem I would be carefull.

[chiller rob]

that is the customers problem...
i am sypathetic to the situation but i would be looking for some P/F's if i wanted to use the YK...
you dont need that liability...

Good Luck...
Rob

[heavymetaldad]

what's wrong with the dk? the transmission designed for that machine is practically bulletproof. r-11 vs. high pressure? i prefer low pressure. take care of the v-bands and put a redi purge on it.
the machines probably weren't installed to codes. if the new old ones rupture youre liable. will they hand grenade - probably not. will withstand at least 50% over design.
i wouldn't thou, lawyers do get rich over technicalities
looks like you're a little short on gpm required for your new old machine.
boosting the gpm thru the yk will throw off the flows of the building, unless you do something exotic? like a bigger pump for the gpm for the machine? and short circuit some of the extra flow back thru the machine?
too many if's. too much liability. fix the carrier

[klove]

what's wrong with the dk? the transmission designed for that machine is practically bulletproof. r-11 vs. high pressure? i prefer low pressure. take care of the v-bands and put a redi purge on it.
the machines probably weren't installed to codes. if the new old ones rupture youre liable. will they hand grenade - probably not. will withstand at least 50% over design.
i wouldn't thou, lawyers do get rich over technicalities
looks like you're a little short on gpm required for your new old machine.
boosting the gpm thru the yk will throw off the flows of the building, unless you do something exotic? like a bigger pump for the gpm for the machine? and short circuit some of the extra flow back thru the machine?
too many if's. too much liability. fix the carrier

Based on your situation, I agree with everything here (and in the other 2 posts as well). Once you replace equipment that wasn't to current code because of it's age, you're liable to bring things to code. Unless the
DK's trashed, I'd fix it rather than installing a new/old machine, and that gets you out of hock with the owner/inspector/lawyer/anyone else concerned. If you have to go with the YK, you need to look at your pump curves to determine if what you have will run out without cavitating, or if you need new pumps, if you're planning on running at rated flow for the chiller. Another thing to consider is backing the flow down on the YK and increasing TD so that it doesn't screw up the current system balance. As long as you maintain minimum flow or better, you shouldn't have problems with the machine as far as diffusion into the tube bundles is concerned. Drastically lowering flow can create issues with hunting, capacity control, etc.

[CaptJackSparrow]

We have 2 DKs. The one I want to replace has been wet and was open for some time. Oil filter plugs ect ect ect........

This is a back up machine. The building requires allot of winter time part load capacity. My thinking was to scrap the DK install a "used" yk vith a VSD that has never been started to run as lead in the light load months. I can install this machine at 50% or less than the cost of a new machine and gain some part load efficiency plus a reliable back up.

Still unclear about the 150lb issue though.

Thanks for your reply's! I have come to respect allot of folks on this site!!!

[HVAC9900]

Regarding the liability, one thing I learned from a lawyer was you assume all liability for the equipment if you are the last one to touch it.Even if you had nothing to do with whatever the liability issue is.

I would not use the 150#,unless you could get a pe and the code enforcement to sign off.Take a bottle of hard liquor and talk fast.
Would be a good way to make the sale and cya.

[Randy S.]

Are there three pass 300 pound water boxes available?
Will the tubes take the higher pressure?

[klove]

Are there three pass 300 pound water boxes available?
Will the tubes take the higher pressure?

Yes to both.