[RE-wrenches] SDHW and High Mains Pressure

Peter Parrish peter.parrish at calsolareng.com
Mon Dec 8 11:48:50 PST 2008


Great! I was looking at their Model 70 Spec sheet. I will go back and read
the specs on the Model 70 as well as the Model 500 more carefully. 

 

- Peter

 

Peter T. Parrish, Ph.D., President
California Solar Engineering, Inc.
820 Cynthia Ave., Los Angeles, CA 90065
Ph 323-258-8883, Mobile 323-839-6108, Fax 323-258-8885
CA Lic. 854779, NABCEP Cert. 031806-26
peter.parrish at calsolareng.com 

  _____  

From: re-wrenches-bounces at lists.re-wrenches.org
[mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of Christopher
Freitas
Sent: Monday, December 08, 2008 10:42 AM
To: RE-wrenches
Subject: Re: [RE-wrenches] SDHW and High Mains Pressure

 

All of the pressure reducers I have seen work at no pressure - I think you
are misreading the specification sheet - the zero drop at zero flow is
referring to pressure drop due to flow - not due to the function of the
regulator - its sort of like zero voltage drop at zero amps.

 

The spec sheet on the Wilkins model 500 does say "The assembly shall be of
the balanced piston design and shall reduce

pressure in both flow and no-flow conditions."  

 

I don't think they would sell many if they didn't reduce the pressure under
no-flow conditions.  

 

 

Christopher

 

 

Christopher Freitas

Director of Research and Development 

OutBack Power Systems, Inc.

 <mailto:cfreitas at outbackpower.com> cfreitas at outbackpower.com

Tel 360 435 6030

Cell 360 202 4239

19009 62nd Ave NE 

Arlington WA 98223 USA

 <http://www.outbackpower.com/> www.outbackpower.com

  _____  

From: re-wrenches-bounces at lists.re-wrenches.org
[mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of Peter
Parrish
Sent: Sunday, December 07, 2008 3:22 PM
To: 'RE-wrenches'
Subject: [RE-wrenches] SDHW and High Mains Pressure

 

We are getting ready to install a SDHW system for a customer and we looked
at a number of things regarding his current set up. I just posted a question
about tankless heaters but I wanted this query to be a separate one. The
customer's mains water pressure is 88 psi on a Saturday afternoon and some
time over the next 18 hours, the pressure went as high as 96 psi. I
understand that 80 psi is the high end of the safe range in general and that
96 psi on a regular basis can/will damage valves and possibly trigger T&P
valves on water heaters.

 

At the recommendation of a plumber I know I looked into pressure reducers,
specifically the Wilkins/Zurn line. All the Wilkins regulators produce zero
pressure drop at zero flow. What good are these products in protecting
plumbing systems from high mains pressures at night when pressures tend to
be the highest and usage is at a minimum or even zero?

 

Are there products that will prevent system pressures from exceeding a set
point (e.g. 60 psi) under any flow condition including zero?   

 

- Peter

Peter T. Parrish, President
California Solar Engineering, Inc.
820 Cynthia Ave., Los Angeles, CA 90065
Ph 323-258-8883, Mobile 323-839-6108, Fax 323-258-8885
CA Lic. 854779, NABCEP Cert. 031806-26
peter.parrish at calsolareng.com 

MESSAGE CONFIDENTIALITY NOTICE:

This message (including attachments) is covered by the Electronic
Communication Privacy Act, 18 U.S.C. sections 2510-2521, is confidential,
and may also be protected by attorney-client or other privilege. If you
believe that it has been sent to you in error, please do not read it. If you
are not the intended recipient,you are hereby notified that any retention,
dissemination, distribution, or copying of this communication is strictly
prohibited.  Please reply to the sender that you have received the message
in error, then delete it. Thank you.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20081208/e4f066ba/attachment-0004.html>


More information about the RE-wrenches mailing list