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msgale
06-11-2009, 11:26 AM
can a one inch swing check valve be placed in a vertical pipe and still worK? Or do they have to be horizontal?

It's for near-boiler piping, to prevent domestic hot water heater usage improperly getting hot water to the house hydronic system in summer

jadnashua
06-11-2009, 02:45 PM
A little more info would be required. There should not be any cross-coupling between hydronic and potable water. Do you have say a demand type system in your boiler you shut off for the summer and use a tank instead? I'd consider just using a valve(s) to shut one off and open the other.

Check valves can (normally) go horizontal (properly oriented) or vertical. If this is for potable water, you'll need probably a bronze, SS, or plastic approved for potable water use. Being hot may create some other problems.

msgale
06-11-2009, 06:01 PM
this is for the water heated by the mod-con boiler in a hydronic system. Now, its a primary/secondary set of loops, one zone only.

The revision is to add an indirect water heater. For summer use of the water heater, i need check valve to protect against boiler-heated water going thru the house radiators.

none of this is potable water. the heated hot wster for human use is on a separate set of pipes

kingsotall
06-11-2009, 06:06 PM
Indirect water heater. Check valve goes after DHW pump before the tee where the return from the sysytem goes into the boiler. On the verticle is fine with a swing check.
Might want to wait for Thatguy, nhmaster or HJ to weigh in with their opinions.

nhmaster
06-11-2009, 06:18 PM
What you need is a flow check valve which is not like a regular swing or ball check in that it has a weighted gate. Check out www.taco-hvac.com What you probably want is a Taco 219.

msgale
06-11-2009, 06:29 PM
tried the web site, no luck

msgale
06-12-2009, 09:21 AM
How is that different or better than a plain swing check valve?

nhmaster
06-12-2009, 07:04 PM
The check in a standard swing check is not heavy enough to always stay closed against thermal migration. A flow check has a heavier check assembly.

msgale
06-13-2009, 03:34 AM
ok, sounds reasonable, thank you , all of you, for the info.
I love this board