circ. pump question

[Donl]

Here's some pic's of the primary tank.

I can see how hot water gets from boiler to primary tank, but how does hot water get from boiler (or primary tank) to storage? How does hot water get from storage to primary tank? Are you going to use two pumps from primary tank to storage, one going one way and one going the other? How would you control that?

I'm not sure yet Eliot . Do you or anyone else have any ideas.

Thanx Huff

Do you have a diagram of your plan?

Heres a rough sketch Don . There are 1-1/4" ports plumbed into the primary tank for the storage already.

I would ensure that flow to/from storage does not push cooler water into the top of the primary tank. Several ways to do this, opposing circulators, 4-way valve etc. in storage loop. You also want to prevent water flowing into the storage tank that is cooler than what is already in the storage tank. This all requires a bit of smarts (system control).

 

[huffdawg]

[
]


I would ensure that flow to/from storage does not push cooler water into the top of the primary tank. Several ways to do this, opposing circulators, 4-way valve etc. in storage loop. You also want to prevent water flowing into the storage tank that is cooler than what is already in the storage tank. This all requires a bit of smarts (system control).[/quote]

Would having a pump pulling from the top of the primary to the bottom of storage then from the top of storage to the bottom of the primary work . Wouldnt it be like one big storage tank then?

Huff

 

[Donl]

[
]


I would ensure that flow to/from storage does not push cooler water into the top of the primary tank. Several ways to do this, opposing circulators, 4-way valve etc. in storage loop. You also want to prevent water flowing into the storage tank that is cooler than what is already in the storage tank. This all requires a bit of smarts (system control).

Would having a pump pulling from the top of the primary to the bottom of storage then from the top of storage to the bottom of the primary work . Wouldnt it be like one big storage tank then?

Huff[/quote]

I don't think that is a good strategy. During charge, you only want to push hot water into the top of storage while drawing cooler water back to the boiler from the bottom. Same for the primary tank. Always ensure hot water always enters the top of the primary tank and that cooler water is drawn off from the bottom.

I don't think you can look at this in the same way as two storage tanks in series. Your plan is quite different than this. With two tanks in series, during charge you want to push hot water onto the top of the first tank, draw cooler water from the bottom into the top of the second tank, then send the coolest water from the bottom of that tank cack to the boiler. During recover recovery the flows should be in the opposite direction. Again your plan is quite different than this.

Always try to prevent mixing so the hottest water is always available for you loads.

Hope this helps.

Don

 

[huffdawg]

[
]


I would ensure that flow to/from storage does not push cooler water into the top of the primary tank. Several ways to do this, opposing circulators, 4-way valve etc. in storage loop. You also want to prevent water flowing into the storage tank that is cooler than what is already in the storage tank. This all requires a bit of smarts (system control).

Would having a pump pulling from the top of the primary to the bottom of storage then from the top of storage to the bottom of the primary work . Wouldnt it be like one big storage tank then?

Huff

I don't think that is a good strategy. During charge, you only want to push hot water into the top of storage while drawing cooler water back to the boiler from the bottom. Same for the primary tank. Always ensure hot water always enters the top of the primary tank and that cooler water is drawn off from the bottom.

I don't think you can look at this in the same way as two storage tanks in series. Your plan is quite different than this. With two tanks in series, during charge you want to push hot water onto the top of the first tank, draw cooler water from the bottom into the top of the second tank, then send the coolest water from the bottom of that tank cack to the boiler. During recover recovery the flows should be in the opposite direction. Again your plan is quite different than this.

Always try to prevent mixing so the hottest water is always available for you loads.

Hope this helps.

Ok makes sense Don! I guess there is no such thing as a two direction circ pump . Back to the drawing board I guess.

Don[/quote]

 

[Donl]

[
]


Ok makes sense Don! I guess there is no such thing as a two direction circ pump . Back to the drawing board I guess.

look for plans the show either opposing pumps with no check valves , or using a 4-way valve. That will do it for you.

Don

 

[huffdawg]

[
]


Ok makes sense Don! I guess there is no such thing as a two direction circ pump . Back to the drawing board I guess.

look for plans the show either opposing pumps with no check valves , or using a 4-way valve. That will do it for you.

Don

Thanx Don .HR and EW. for pointing out the options . I think I will go with the 4 way valve . I found a danfoss Esbe series 90 electronic motor actuator withe Esbe 4 way rotary valve by Danfoss

 

[Donl]

[
]


Ok makes sense Don! I guess there is no such thing as a two direction circ pump . Back to the drawing board I guess.

look for plans the show either opposing pumps with no check valves , or using a 4-way valve. That will do it for you.

Don

Thanx Don .HR and EW. for pointing out the options . I think I will go with the 4 way valve . I found a danfoss Esbe series 90 electronic motor actuator withe Esbe 4 way rotary valve by Danfoss

That's exactly what I have been using, works well! Where did you find yours, Huskers is looking for a motor/actuator to power his 4-way valve.

Draw a new diagram when you have time so we can look at it.

Don

 

[huffdawg]

[
]


Ok makes sense Don! I guess there is no such thing as a two direction circ pump . Back to the drawing board I guess.

look for plans the show either opposing pumps with no check valves , or using a 4-way valve. That will do it for you.

Don

Thanx Don .HR and EW. for pointing out the options . I think I will go with the 4 way valve . I found a danfoss Esbe series 90 electronic motor actuator withe Esbe 4 way rotary valve by Danfoss

That's exactly what I have been using, works well! Where did you find yours, Huskers is looking for a motor/actuator to power his 4-way valve.

Draw a new diagram when you have time so we can look at it.

Don

Here's a link http://www.danfoss.com/North_Americ...aea/e5ed9670-e81a-4d28-8141-26fad4d87770.html

http://na.heating.danfoss.com/PCMPDF/Danfoss ESBE Series 90.pdf

I dont't have the actuator and rotory valve yet. I am at work for another 10 days, but will try and order it through Andrew Sheret. the local plumbing supply here.
I will try and make up another sketch tonight at work.
Cheers

 

[huffdawg]

I took a screenshot of HR's drawing above. I will plumb my storage and separator tank together the same as it.

 

[huffdawg]

Flow reversal can be done a couple ways. On mine I have two pumps facing each other. But remember the internal checks need to be removed I'm not that pleased with the operation it tends to thermosiphon when the checks are left out.

I will try a 4 way valve with a motor that drives it from one extreme to the other. I had a sample of this valve a few years back to correct a radiant job that had a 1000' loop installed! The valve would flow into the loop from one end for 30 minutes, then flow from them other for 30 minutes. It actually did help the floor temperature even out by flip flopping the flow.

The valve was built up by Leif at Paxton. Basically it had a Honeywell 24V actuator motor bolted on. I think Bellimo also offers this actuator.

So when the boiler tank is hot a ∆ T control starts the pump with valve allowing flow as in the top drawing. When the storage is within 5 degrees of the boiler tank the pump stops. A second ∆ T function would start them pump, flop the valve and take that energy out of the storage and back to the boiler tank.

At least that is how I imagine this control logic to work. I'm open for suggestions.

The heat loads all pull from that boiler/ separator tank.

hr

Hi Hr I am confused, all the 4 way rotory valves I've been looking at are mixing valves. Can the mixing valve be used for flow direction control as well?
I'm guessing you have to get the actuator to either have them in the fully open or fully closed position .



Huff