Zone not circulating to all baseboards well. Purging air question

HomeownerDustin

The zone with the red circulator pump doesn’t heat all the baseboards well. The circulator does work. I want to purge air from that zone but the drain valve is between circulator and the boiler. To purge air, can I just use the shutoff below the circ (above the return trunk) and let it flow out of that existing drain valve? Or do I need to add a drain valve prior to the circulator pump and upper shutoff? There are no other drain valves on that loop.

It seems to me that the circulator pump allows water to flow through it without needing to be manually "opened"—when I close that lower shut off valve and open the spigot, water does come out. But on videos the drain valve seems to be prior to the circulator.

Lastly, what is that brass thing between the upper shutoff and the circulator pump?

EdTheHeaterMan

Close the valve below the circulator and open the drain valve below the circulator, just above the valve you just closed

the brass thing is a check valve. each zone needs a check valve of some type to prevent reverse flow thru a zone that may be turned off.

hot_rod

I like to see the checks on the discharge side of the circs. That looks to be on the inlet side?

Yes to purge shut off the ball valve attach hose to the purge valve above it.

If it has a fill valve you want it in fast fill position to get adequate flow to get a good purge.

Do one loop at a time, start with the longest loop.

HomeownerDustin

yes the check valve is on the inlet side. Would it be smart to add checks on the discharge? I’m wondering if water is being forced against current and stressing That circ pump motor?

Interestingly, the circ pumps on the left and right are jumped to operate with the same thermostat.

hot_rod

it also looks like a swing check which is not ideal on a hydronic system

Some pumps allow you to out a check inside them. A check 6” downstream is best

But that would take some repiping

Im not sure why multipe zone circs would be wired together ? Sometimes combining zones helps lessen short cycling of the boiler.

HomeownerDustin

https://forum.heatinghelp.com/discussion/comment/1812561#Comment_1812561

I'm okay to repipe a little. I have a press tool, so it shouldn't be too bad (famous last words)

Would this check valve be appropriate? P-450NL Press Inline Check Valve This zone serves a third floor about 30' above.

The two zones that are jumped together serve rooms that have been "opened up". I'm definitely going to need to separate and add a thermostat when we put up some walls when remodeling.

hot_rod

I have not used that brand, I see it has a 1 psi crack pressure, the hydronic checks in the pumps are .50 psi, I believe. A small circ on low speed may not hold that open? I would have to try that. If it is listed as a hydronic check, it should work

Another option is this serviceable type, they do clog, stick, or need replacement from time to time

IMG_8697.png

HomeownerDustin

Sorry for the basic questions and thanks for the assistance. Is a check valve needed if it has one integrated? My Grundfos spec sheet says "pump with built-in isolating and non-return valves"

EdTheHeaterMan

That appears to have the internal flow check, so an external flow check is not necessary on that loop, unless the IFC has failed or was removed or was not included with that circulator pump.

hot_rod

There are date codes on the 2 Tacos circs. That may help determine if they have, or could have internal checks. That would be the easiest out.

SteveSan

https://forum.heatinghelp.com/discussion/comment/1812614#Comment_1812614

The green Taco pump nameplate just says 007-F5 so more than likely just a standard without the IFC ( if it did, would have an IFC in the model number ).

The black Taco pump ( can’t see the tag ) probably an OEM, maybe Weil McLain or US Boiler ( Burnham ). If the standard 007-F5 is dated before 2016, then definitely doesn’t have an IFC. Hope this helps.