We are working on a project where the site engineer is asking if tapping into the underground fire line is acceptable to supply a water cooling line to a water source heat pump unit with a 3-inch line. I'm having trouble finding where it is not acceptable and thought I'd reach out to the knowledgeable members here. This site has a combination potable/fire line as shown in the picture below. Should we require them to tie into the 8-inch tap from the potable water line upstream of the fire protection vault (blue line in the drawing)? Or is it OK that they tap into the fire supply line downstream of the fire protection vault (red line below)? Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe
8 Comments
Franck
9/1/2021 08:38:33 am
To my understanding, it would be (more or less) the same as having a process water supply as a fire protection water supply.
Reply
Glenn Berger
9/1/2021 08:39:19 am
You will not find any prohibitions from a fire protection standpoint. This is strictly a local jurisdiction item.
Reply
Alex
9/1/2021 09:06:09 am
Hi Anonymous,
Reply
John G
9/1/2021 09:09:04 am
I don’t believe your picture is indicative of your proposed design for a combined closed loop , circulating, heat pump/fire sprinkler system. ( section was removed temporarily in 2016 edition of 13)
Reply
Casey Milhorn
9/1/2021 09:33:43 am
More of a local water department issue in my eyes. Typically I see double detector check valve assemblies in most jurisdictions for dedicated fire lines. So could be a couple issues here. I would assume that the water department would want a reduced pressure backflow for any potable water connection like this, even though it is more for process piping. Additionally as someone mentioned, you are probably either unmetered (DCVA) or more likely, metered (DDCVA) but they are not meant for accurate continuous water usage. They are more to detect out of the ordinary water usage. By the fact that you show a vault, that means more than likely you don't already have a RPDCVA or RPDDCVA. Some other issues I can think of would be maintenance related or pressure related. If/when the fire protection backflow is being tested/repaired/forward flushed you will lose supply to the heat pump (or any other impairment to the fire line). You could also have an issue if the FDC is not isolated from heat pump, so during pressurization could cause issues to pump.
Reply
Greg
9/1/2021 12:58:02 pm
Has the water utility performed a study or engineering assessment that identified this (new) use? Their understanding of water use, pressures, backflow, etc. is aligned with your design objectives, as the end user of the water, as a customer. Can you lean on their studies (or commission a study) to help bolster the confidence of the sprinkler design, both now and future expectations of heat pumps as a demand on the water utility.
Reply
3/15/2022 04:44:05 am
Automatic sprinklers are the most reliable and effective fire protection devices available today provided they operate correctly. To determine if a sprinkler system can adequately protect a property, underwriters should be familiar with the components, operation, and testing of the systems, as well as potential causes for failure.
Reply
7/22/2022 08:54:45 am
Heat pumps come with multiple advantages for your home. Pumping the heat uses less electricity as compared to when electricity is solely used as a means to convert it. During the summers, the cycle can be reversed and the unit acts like an air conditioner.
Reply
Leave a Reply. |
ALL-ACCESSSUBSCRIBESubscribe and learn something new each day:
COMMUNITYTop September '24 Contributors
YOUR POSTPE EXAMGet 100 Days of Free Sample Questions right to you!
FILTERS
All
ARCHIVES
October 2024
PE PREP SERIES |