Grooved Piping Systems in HVAC applications

[belz]

I am considering allowing grooved piping systems (Victaulic) on a 240F heating hot water system and a 42F chilled water system. What are positive and negative aspects about using this system in HVAC applications? In my city grooved systems are often used in fire protection systems, but rarely in HVAC.

 

[TBP]

I believe that most of the problems people have suffered using grooved piping in systems like this, is due to faulty design and or installation. If the people at Victaulic or GruvLok (there could be others) are consulted about what kind of couplings & gaskets should be used, and how to lay out the system, there should be no problems. The systems that I've seen with problems, were pretty much due to expansion issues that weren't dealt with properly. If the job is being done by the "low bidder", somebody needs to be paying attention that the system is being installed correctly. Grooved joints are expensive, and every one that the contractor can eliminate, is money in his pocket.

 

[imok2]

We have installed many Victaulic systems on chilled and hot water and they work fine. As was entioned, if the installer is qualified there should be no major problems. Victaulic® originated the grooved piping method in 1925 to provide fast, easy assembly for a wide range of applications. It is generally more economical than welding, threading or flanging, offering total installed cost savings of 10 to 30 percent compared with these alternatives. You can use either steel or PVC.See the web site at:

http://www.victaulic.com/servlet/RetrievePage?site=Victaulic&page=about_text

 

[belz]

Thanks TBP and IMOK2 for the information.

 

[Fitterguy]

I operate a Victaulic system designed to operate at 230 deg. F. This system was installed in 1982,and has been in continuous use since. When I came here in 1990 the system had to be operated at above 160 deg. F at all times to stop leaks from happenning. By 1998 we had to operate at 180 deg. F to stop leaks and had to replace a complete secondary heating loop to stop leaks. This was because if you disturbed the lines to fix a leak it created several more leaks in jionts near bye.

In 1999 we replaced nearly 2000 gaskets ranging from 10 inch to 2.5 inches. This was done in consultation with Victaulic as to the best method to redo the gaskets. Since then we have had a policy of not exceeding 223 deg F because Victaulic has stated that even a short time of use over 230 deg. F (this is also the tempurature that they will warranty their gaskets to) will cause rapid deterioration of the gaskets. For three years we had no problems but then we started getting leaks in 2003 and as of this year we once again have to either drain the lines or leave them hot at about 120 deg. F to prevent leaks.
In fact we are now looking at welding all the jionts as it is very expensive when we have a leak and it destroys our clients product.
My question is has anyone designed and operated a Hot Water Heating system that operates at 220 deg. F to 230deg. F and if so how long has it operated trouble free.
A couple of quick facts: gaskets are Victaulic recommmended EPDM and only victaulic grease was used & our water treatment is by GE with a compatible product.

 

[lilliput1]

We usually use 180°F supply and 160°F return. I have seen systems at 200°F but not higher unless it is a high temperature hot water system (HTHW)in the range of 300 to 400°F but these required welded piping and high pressure to make sure you don't get boiling. Water at athmospheric pressure boils at 212°F so for normal hot water systems 200°F is the recommended limit.

 

[AEBuck]

I think we can all agree that there's generally no problem with the chilled water application. As for medium temperature heating water application, I don't believe the risk is worth the reward.

I am personally aware of a Victaulic heating/cooling changeover system in a building that issued umbrellas to all occupants. Not my project, and not aware of the final outcome, but inappropriate gaskets and/or poor workmanship were being considered as the leading culprits.

 

[friartuck]

Consider plastic pipe for the chilled water. Go to GF or similar. Plastic pipes comminly have a 60 year life span and dont corrode. I have seen plastic mains cold water pipework that is ancient (30years and over)and is still in good condition.


Friar Tuck of Sherwood