Circ Pumps or Zone Valves?

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velvetfoot

Minister of Fire
Dec 5, 2005
10,202
Sand Lake, NY
Would there be any advantage is going to zone valves from circ pumps (2 or 3 zones)?
I can see installation cost and energy savings with one pump and several valves.
Reliability and tunability for individual zone characteristics might be on the side of the multiple circ pumps.
Any opinions on which is better?
 
With one pump there is an electricity savings that can be realized to a greater extent with the new smart circulators (Alpha). The down side it the whole all your eggs in one basket deal, your main pump dies you done, with multiple you can still limp along.

I have the single with zone valves. Works pretty well.

K
 
I wonder if the new pumps are more susceptible to electric malfunctions, caused by electrical surges, power quality, etc, as well?
 
No idea.

I'm running a Taco 007 series pump, it just keeps on trucking but is in no way "hi-tech".

K
 
I would be replacing a couple of 007s which have also been very reliable. With heating, reliability means something.
 
With one pump there is an electricity savings that can be realized to a greater extent with the new smart circulators (Alpha). The down side it the whole all your eggs in one basket deal, your main pump dies you done, with multiple you can still limp along.

I have the single with zone valves. Works pretty well.

K

Same here. I did replace my 15-58 with an Alpha last year - it is a really nice working pump. I have 5 zone valves it pumps through, it ramps up & down as zones open & close very nicely. The 15-58 wasn't even a year old - so it's a spare now. I can get by in a pump failure or power outage though pretty good by just opening my zone valves manually & letting them convection flow.

Also, as far as I know, with the Alpha, you don't even need to wire the zone valves to the pump. The pump will sense a valve opening by the small pressure differential created, and ramp itself up - you can get them with a plug end on them, you just plumb it in & plug it into a wall outlet. That could be a pretty big convenience too - looking at the mess of 24v wiring I have around my zone valves.
 
I read here once before that plumbers zone with pumps and heat men zone with valves...if that helps

I guess I hired a bad plumber...I'm running all pumps for my system.
 
But should you replace them with more efficient pumps, if there aren't too many of them?
I was looking at some high end zone valves this afternoon, and they aren't exactly cheap.

I have 1 pump (Taco 00R 3 speed) that pushes supply water from the WG to the primary loop hanging on the wall in the basement 70' away
Then I have 1 pump (Taco 007) on the primary loop circulating water around the loop.
Then I have 1 pump (Taco 007) for each of the 3 zones, first and second floor, dhw.
Only when a zone calls do the pumps turn on.
So if one zone calls there are 3 pumps running, but if all three zones call then there are 5 pumps running.

My concern is not so much about electric but more about am I pushing water to fast through the baseboard emitters that I am burning more fuel than if the water circulated slower.
BUT, I spoke with someone, just a smart engineer friend, who said theres no truth to that.

What say you?
 
Me? I have no idea. But I do seem to be getting some water noise in the first baseboard after an elbow off the supply header, which I'm thinking could be velocity related.
 
Me? I have no idea. But I do seem to be getting some water noise in the first baseboard after an elbow off the supply header, which I'm thinking could be velocity related.


I don't get "water noise" but I do get a general humming or resonance when a zone calls that can be heard through the baseboard.

I've gotten used to it and its kinda like an alarm to let me know that a zone is on.
Since I don't have storage it makes me think about the last time I loaded and how much wood might be left and whether I should add some more wood.
 
5 zone valves one pump , soon to be 6 . Tried a taco bumble bee on set point but much happier with the alpha pump for the main pump
 
I read here once before that plumbers zone with pumps and heat men zone with valves...if that helps

I guess I hired a bad plumber...I'm running all pumps for my system.

Guess that makes me a plumber. LOL
 
I'm planning in using two circulators - one will handle two zones in the basement, the other two zones on the first floor. The zones will have zone valves. I figure this way, if one pump goes out, it won't take the all the zones out.
 
Taco Sentry zone valves are $75 online, Alpha Grundfos pump is $150 online. Sentry valves use almost no electricity when they are on (<1.5w) and an Alpha will draw 8-30 watts in most circumstances when running. If you use circ pumps, a standard 007 Taco will run about $75 also, but you really should sweat in another flow check ($20 or so each zone) since the IFC's don't work well on the pumps. The circ pumps will cost a lot more to run over the life of the unit.
 
Well, I've got 3 007s AND separate check valves. :)

But seriously, do those Sentry valves consume any power when they are not activated? Are they normally closed, and open when activated?
My point is, if the valves consume electricity when not activated, that could be a factor.
 
With zone valves you don't need and IFCs or weighted flow checks, this is a plus to ZV install IMHO.

TS
 
I've been very happy with Caleffi Z-One zone valves. Pretty much any zone valve other than the Taco ball valves use 5-10 watts, and the old Taco Gold wax heat motor valves use considerably more.

TS
 
I've been very happy with Caleffi Z-One zone valves. Pretty much any zone valve other than the Taco ball valves use 5-10 watts, and the old Taco Gold wax heat motor valves use considerably more.
Looking at the specs, I can't tell how many watts they use when not in use. Can you please tell me:
Actuator
Material: - base and cover: polycarbonate
- base plate: aluminum
Motor: - AC voltage: 24 V - 120 V - 208 V - 230 V - 277 V; 50/60 Hz
Power requirements: 5.0 W, 7 VA
Power connections: - Terminal screws with auxiliary switch: 24 V only
- Wire lead length: 18” (45 cm), 24 V only
6” (15 cm), 120, 208, 230, 277 V
Auxiliary switch: 0.0 A min, 0.4 A max, 24 V (24V only)
0.25 A min, 5 A max, 250 V (Z111000 HCS)
0.25 A min, 5.0 A max, 250 V (120, 208, 230, 277 V actuators)
Ambient temperature range: 32 to 104°F (0 to 40°C) 24, 120 V
32 to 170°F (0 to 77°C) 208, 230, 277 V
Humidity: 95% non-condensing
Full Stroke Time: - On: <60 seconds
- Off: 6 seconds
Approvals: UL873, cUL Listed & CE
UL 1995 sec. 18 approved for air plenums and ducts,
Normally Open Actuators must be powered down during off-season

When the install instructions say Power Consumption, Power On: 1.44 Watts, 0.06 Amps
Do that mean it Always consumes at least 1.44 Watts, even when not activated?
 
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I can't tell what this means either for the Sentry:

Product Specifications Max. Operating Pressure ...300 PSI (2100 kPa) Max. Shutoff Pressure ........125 PSI (875 kPa) Fluid Temperature Range ...20-240˚F (7˚-115˚C) Service ...................................Water or .....................................................Water/Glycol up .....................................................to 50% Glycol .....................................................Close Systems Ball Rotation Speed ............(90˚ turn), ................................................Approximately ................................................5 seconds Electrical Rating ...................24 VAC, 60Hz ................................................0.48 Amps Power Consumption ..........11.4 W, 0.48 Amps Power Consumption ..........1.44W, 0.06 Amps Heat Anticipator Setting ....0.5 Amps End Switch Rating ...............1 Amp @ 24 VAC
 
With a variable speed pump, if one zone valve open uses 4 watts, wouldn't two zones likely use 8 watts? How different is that from two of the same pumps operating at the same time plus any valve power useage?
 
The sentry valves use no power when off. They use 14w to charge the capacitor to operate the valve to open. It charges for about 30 seconds. It uses about 1.4w to keep the capacitor charged so when the call for heat goes off it can close right away.

You can disconnect the head from the valve mount and actuate it. When the head now thinks its open, rotate the head back to the mount position and now its a normally open valve. Meaning it needs a signal to stay closed and will open on loss of power.
 
VAR speed grundfos pump on my system uses 8w for my main zone and 24w for 2 zones (not linear flow... goes from 1gpm to 4gpm due to far less elbows in second zone.)

You could use multiple grundfos alpha pumps... but at far higher purchase cost.... $150 pump vs $75 ZV that uses even less electricity.

Perhaps I didn't understand your question right?
 
I was kind of doing a generic valves vs. circs to generate interest and discussion, but of course, it's always about me. :)
I'd like to get educated too.
If one zone has different flow requirement than the other, like yours do, what if you wanted to have a target of 1 gpm for each one? With individual pumps you could dial them individually.
I'm thinking the pumps would also be more reliable.
For me, I could just change out my old distribution circulation pumps for new pumps. It's not looking like I'll need to go through the hassle of replacing them with zone valves. Eeezzee Peeezzee.
Now, the question is what to do about the boilers' circ valves. I'm assuming a similar pump would probably do the trick as well. As I recall, they require a certain amount of circulation-I think the pellet boiler may be 7 gpm, not sure. The pipe connection on the buffer tank is 1.5", not sure of the boiler. I think those boiler pumps might actually see changing flows compared with the distribution zone circ valves if both, or one, or none are on and the tank is being charged.
 
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