Ghost Flow Help

Eastendmedic

I have an oil fired furnace with three zones (upstairs, downstairs, domestic HW). The downstairs zone has hot water flowing through it whenever the DHW calls for water. Replaced flow checks and added isolation/purge valves after the flow checks. The upstairs zone remains cool unless thermostat calls for heat. Thermostats are off!! If I shut the downstairs zone off by closing ball valves before circulator and after furnace the zone remains cool. I am wondering if it could be the taco 007 circulator or should another flowcheck be installed. Feels like I have radiant heat but furnace seems to be kicking on alot more as I asume it is tryint to maintain temp for the loop as well at DHW. Any help appreciated!!

HVACNUT

I only ask this because I did it once when my hands were moving quicker than my brain.
Did you remove the piece of cardboard from inside the flo valve?

Eastendmedic

Yup...did that. Purged the air from system with a pump....trying to see if I am missing something, need a new circulator, or the system is plumbed incorrectly...new to me house.

Eastendmedic

Another image if it helps.

EBEBRATT-Ed

Everything looks like the piping is correct. Are you are sure the flow check is piped correctly, cardboard removed and flow check adjustment in the automatic position? Maybe pipe dope or Teflon tape inside the flow check. Take apart and clean or replace again.

Also are you sure that the circulator for this zone is actually off and not running when the thermostat is not calling

NY_Rob

If the return end of the downstairs zone is getting hot before the supply end (with the DHW circulator running), that flo-check is not closing down regardless if it's new or old.
If you got it from Home Depot it could have been a defective return they put back on the shelf.

HVACNUT

Assuming the water heater was doing its job, providing hot water during the summer, no wires are crossed?
Do you have a voltmeter? In the Argo board, is there 115v at C1,C2 for the 1st floor zone when the water heater zone is running, but 1st floor thermostat is off?
It's not piped correctly by today's standards, but it is piped correctly for the application.
No need for purge stations on the supply the way it's piped.
And don't purge with a pump. Purge from the returns, one at a time.
It's not a bad circ. If it's running during a DHW call, then it's the Argo board or its not wired correctly.
If you don't have a voltmeter, disconnect the hot wire from C1 for the 1st floor in the Argo. Put a wire nut on it.
Tomorrow after the water heater cycles, see if the problem is still there.

The top of the flo valve is screwed down tight?

Eastendmedic

Thanks for all the replies:

Ok a bunch of stuff to reply to:
I had discovered this issue this summer when I noticed that the central air was having a hard time cooling and realized the hot water hydronic loop was hot as hell...pseg loved me...the thermostats were either off or in cool mode. Friend of mine who is a plumbing mechanic helped me replace flow checks and sweat in valves.

I purged the air in lines after opening up the system to replace the flowchecks(removed cardboard and purchased from a reputable trade supply) and sweat in the ball valves after the checks.

DHW worked all summer and as I closed the ball valves to the downstairs zone and it stayed cool. I opened up the ball valves the other day but did not turn on the thermostats and the downstairs zone became hot again.

I disconected the Wire to that zone to the argo and it still got hot even though the only circulator running was DHW.

Currently the heat is off but the DHW just ran and the motor for the first floor zone is hot! But Second floor is cool!

Top nut for flow valves screwed down tight.

HVACNUT

The direction is correct on the flo valve? Arrow pointing towards the copper.
Looks like a bad flo valve.
You can replace it or install a 3/4" Shark Bite spring check on the 1st floor return above the purge station.
I've seen that problem with IFC circs pumping away, using speed headers. Heat rise on the zone closest to the DHW zone.
Replacing the IFC didn't fix it, but a spring check did.

Eastendmedic

Ok I just tested the volts and only the DHW has 115 to the circulator when it is running.

Eastendmedic

So the shark bite would restrict flow enough to prevent the thermal siphon effect...which is what I assume is happening...how can I tell if the circulator has flow control?

HVACNUT

> @Eastendmedic said:
> how can I tell if the circulator has flow control?

Yours doesn't. You have the flo valves.
IFC circs are used instead of flo valves when the circs are on the supply side of the system.

Try the shark bite spring check, arrow down. It should solve it.
Don't drain the boiler. Isolate that zone, then just take the pressure off from the return purge valve.

newagedawn

did you check your tstat or relay, maybe one is shorted and calling for heat

NY_Rob

If you want to replace the Taco Flo-Check, Caleffi makes a very high quality inline spring style flow check valve...
http://www.supplyhouse.com/Caleffi-NA51069-1-Sweat-Inline-Flow-Check-Valve-17-Cv


Or, you could also use a pump flange style check valve...
http://www.supplyhouse.com/Webstone-13703HV-3-4-to-1-1-4-Isolator-Double-Flange-Check-Valve


FWIW- I've had bad results with the Taco Flo-Check valves over the years- both times I had ghost flow issues. The spring style flow check's have solved those issues.

Eastendmedic

Any chance the the black circulator motor is too powerful for the DHW storage tank loop and litteraly sucking the water through the other zone? That taco circulator has a different model number?

NY_Rob

^ A properly functioning flow check would stop that from happening if that is what is happening.

On the return side of the loops- once the DHW pump is running you have positive pressure at the flow check... so no sucking there. On the pump side, you could be pulling water from the CH pump if the flow check in that loop is bad.

More likely, the flow check is hanging up and the return from the DHW tank is pushing hot water backwards through the heating loop, and the DHW pump is also pulling it in through the CH circulator.

Eastendmedic

Is there a way to check the flowcheck? Isolate the supply and leave the return open and see what side heats up?

NY_Rob

If the ghost flow is happening on all DHW calls where the boiler fires up- just run it as normal and feel which end of the heating loop heats up first. It will probably be the end near the flow check valve.

Are you on eastern LI?

Eastendmedic

The supply side out if the top of the boiler heats up first...to the flow check...then to the vertical copper...across the ceiling...to the coil...to the return.

Yes I am

NY_Rob

So, the boiler hot water is traveling in the correct direction (from supply to return) on the ghost loop?

Eastendmedic

Seems like it as that side is hot as hell when the dhw kicks on.

Eastendmedic

Could that circulator motor be putting out too much pressure and sending hot water up that zone

NY_Rob

^ The supply side of the downstairs (ghost) zone is getting hot first right?

Eastendmedic

Yes

NY_Rob

Seems like the circulator pump for the downstairs is powering up with DHW calls.

Have you put a voltmeter on the downstairs circulator when the ghosting is happening?

Grallert

I'd pipe the water heater in 1". That 007 is a pretty strong pump and could be sharing a bit of its flow with that heating zone on a long call for domestic water.

Eastendmedic

Would it be easier to just change the pump to a less powerful one?

Eastendmedic

So the boiler just kicked on as I am assuming it just does that to keep up the temp and pressure...the DHW return was cool (no call for hot water), the second floor zone return side was cool...but both the supply and return side of the first floor zone is screaming hot. No circulator came on to call for heat at all. Any ideas

Eastendmedic

The cirlculator had no power going to it

HVACNUT

> @Eastendmedic said:
> So Any ideas

Yes. Install the shark bite spring check.

Eastendmedic

Lol I will to order one...not one local supply house ir home dumpo/ loads had one.

Grallert

With no call for heat or hot water, no power to the pump and the burner running there must be a maintaining control on your boiler? With the low limit at 140 or something? I'd think the flow check is stuck. You could change the pump to one with an internal flow check and if you have a maintaining control you could turn it way down to it's lowest setting and let the water heater maintain the low limit. That zone must always be hot?
Just some thoughts.

Patchogue Phil_2

Eastendmedic said:

Lol I will to order one...not one local supply house ir home dumpo/ loads had one.

Did you solve the problem?

Patchogue Phil_2

> @HVACNUT said:
>
> Looks like a bad flo valve.
> You can replace it or install a 3/4" Shark Bite spring check on the 1st floor return above the purge station.
>

I'm curious why you say to put the spring-check on the return, versus putting it where the Flo-check is on the supply?

Thanks

Jason_13

Did you tighten down the top bolt to verify the valve is closed?