Pressure relief valve regulations

[Pykester1]

Hello.
Could someone tell me where I can find the uk regulations that govern the obligatory maintenance and testing of refrigerant pressure relief valves. I have read that testing is required every 5 years, but I cannot find the specific regulation document.
Thanks.

[Silhouette]

I think it is the pressure equipment directive?

[hookster]

The PED is a very involved document for the layman and although it is the statutory document it can take some understanding.

The IOR service members section is a useful resource and PED etc for refrigerant plants is available to service members.

The IOR Service Engineers' Section is a special interest group for maintenance, service and installation engineers at all levels of experience. It provides technical information and updates for engineers working in the refrigeration and air conditioning field. The Service Engineer material is practical, useful and easily digestible. Service Engineer members receive each year:
Four quarterly mailings with bulletins and updates
Service Engineer Magazine (published by EMAP) delivered to your door
A SES badge
An A4 folder to keep your bulletins in
A cd-rom of past bulletins
Access to the Section members-only areas of the web site
An SES Comparator (featuring all common refrigerants including ammonia)

The subscription fee for new members to the Section is currently £30.00. The membership year runs from April to March. (Discounts are offered for companies wishing to register 5 or more engineers and for students) Overseas members rate £35 a year.

Join now

To join the section please follow this link.
http://ior.oxford-1.co.uk/membership_ses.php

[Spare Parts Man]

How I understand it is that although it is not (UK) law to change them, it is considered good working practise. Apart from the ASHRAE IIAR Bulletin 110, section 6.6.3, Revision: May 24th 2007, I have seen one other trade publication that makes the statement that it is recommended to replace PRVs within five years of previous installation.

Although not law, it has been picked up on primarily by the insurance industry who are extremely careful to reduce claim costs and liability in the (extremely unusual) event that there was a detrimental incident relating to said valves, and so they have been championing this recommendation and are known to pressure building owners with withdrawing cover unless the work is done.

For this reason we have been advising all our clients to consider a programme of installing dual port three way changeover valves either in the winter period or when scheduled works involve de-gassing. We have also suggested that sites keep at least one PRV per pressure vessel in site stock – please note that the stocked valves could be 5 years old but the efficacy of the valve is from the date installed, not supplied.

If any of this is wrong I would be delighted to be educated.

[install monkey]

if your customer is holding spare pressure relief valves on site then if you got a calibration certificate at the time of purchase then it would lapse before fitting- although stampedat a designated pressure its about another 20 quid to get em certified :p

How I understand it is that although it is not (UK) law to change them, it is considered good working practise. Apart from the ASHRAE IIAR Bulletin 110, section 6.6.3, Revision: May 24th 2007, I have seen one other trade publication that makes the statement that it is recommended to replace PRVs within five years of previous installation.

Although not law, it has been picked up on primarily by the insurance industry who are extremely careful to reduce claim costs and liability in the (extremely unusual) event that there was a detrimental incident relating to said valves, and so they have been championing this recommendation and are known to pressure building owners with withdrawing cover unless the work is done.

For this reason we have been advising all our clients to consider a programme of installing dual port three way changeover valves either in the winter period or when scheduled works involve de-gassing. We have also suggested that sites keep at least one PRV per pressure vessel in site stock – please note that the stocked valves could be 5 years old but the efficacy of the valve is from the date installed, not supplied.

If any of this is wrong I would be delighted to be educated.

[Spare Parts Man]

Thanks for that IM, that does differ from what our supplier says, who fortunately doesn't charge £20 for a piece of paper. Do you have a point of reference for me to look at?

Thanks SPM

[install monkey]

http://www.refrigeration-engineer.com/forums/showthread.php?32556-Pressure-Relief-Valve-Calibration
few links on here who do em- ive ordered henry prv's from climate ctr - with certificate usually only a day longer from normal

[Gibbo]

I believe it falls under Pressure System Safety Regulation 2000 (PSSR 2000) It's to do with testing of all safety devices on vessels or pipework which would include PRV's, obviously they can't be tested onsite and therefore you either have to remove it for testing and certification or replace them. The smaller onces such as Henry or Castel are not worth sending off for testing and certification as the cost to replace is probably nearly the same including certification.

The types used on some of the larger chillers could be sent off for strip down, tested and recertified.

From experience the question of whether they have to be replaced or not crops up a lot in fact I am often surprised to find that some sites I have been too claim to have never had a site inspection by an insurance engineer which I find hard to believe.
Zurich Insurance for sure check every chiller on all of their sites and will attend for witnessing the tripping of all High Pressure Switches and also check the condition of the PRV's and their settings in relation to the vessels or systems they are protecting.