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BigRed Member Posts: 104
then the B-room.


  • BigRed
    BigRed Member Posts: 104
    Large building

    I am going to look at a DHW water system in a high rise on broad street tomarrow. The building has something like 500 rooms like hotel rooms and 5 floors of conference halls. Turns out a plummer installed a brand new backflow preventer a couple of years ago.

    He, I assume it was a man neglected to install any provision for expansion at the same time, this has caused some intresting problems in the system. The reliefs on the 2 3,000 gallon storage tanks blow at around 130 deges and that is alot of hot water going byebye not to mention the low tank temp witch is limiting there capacity avalable to there mixing valve and this causes a lack of hot water during peak use.

    An engineer was hired and did a nice report of the system they recommended expansion tanks, and a couple different options to upgrade ther 25 year old boilers. The boilers are modular cast iron and are used for 2 zones, 1 zone is the space heating witch is a water source heat pump system, and the other is 4 tube in shell exchangers for the DHW.

    The first option is to supplement the exsisting boilers by adding 2 copper tube boilers 'leaving names out' these would be enough to almost cover the entire domestic load but not all of the domestic load.

    The second option is to spilt the two system and install two sets of copper fin boilers one for the comfort system and one for DHW .

    I dont agree with the second option and I only a little agee with the first, The piping layout for the first put the new boilers on the same loop as the exsiting tube and shell heat exchangers, on the domestic side. Im tired of typing

    Anyway it sould prove to be intresting I will post pics if there is any interest
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