High Rise Water Pressures

[referteacher]

We have a customer with a pair of 1997 19DR chillers in the basement and the cooling towers 35 stories up on the roof. That makes the pressure 180 psi at the chillers. I know, I know, that's not high at all compared to some you guys work on.

However, Apparently some engineer figured there is a 25% safety factor in waterbox design so the chillers have 150 lb boxes on them. The boxes have held up fine but the cover gaskets are very difficult to seal. They are the traditional Carrier scalloped black rubber with the nylon braid in the middle. To make matters worse, the waterboxes have been epoxy coated last year, including the flanges and covers. So now the sealing surfaces are as slick as ice.

O.K. guys. Let's hear all the secret tricks you have to solve this problem.

[flange]

Here is a secret trick that I love. Get all of the facts on paper. Give these facts to your customer, along with a letter asking for the specifiying engineer to give you the solution, otherwise known as an RFI. You will probably get no suitable response, but will at least go on record with the customer in case of a future problem. We had a client with a plate and frame the was used for free cooling, as well as to warm up the condenser loop by receiving influx of 240 f water when the bas decided the demand was too great for the plate and wanted to start a centrif.This process was designed to occur in thirty minutes. This usually occurred in early spring or late fall. At least six times the plate was rebuilt due to gasketing being forced out from between the plates before he admitted he f'ed up. We finally concerted to a 300 psi rated plate. It was an easy sell because we were on record with the problem before it occurred.