Sizing a Super Store
#1
Member
Thread Starter
Sizing a Super Store
So we need a new hot water heater. We currently have an old old Vaughn 40 gallon tank. It is rusted out at the bottom, the drain valve is leaking and rusted. I would just replace the valve and try to get some more time out of it, but I am afraid that if I try to remove the valve I am going to break something because of all the corrosion. With the current water heater we can only get through 1 1/2 baths for the kids before we are out of hot water. I checked the continuity on both elements and they seem good.
We have one full bath with another 3/4 bath being built now. We have a dishwasher and a washing machine. I can get a 40 gallon superstore for $500 that is brand new. I already have a pump and I am assuming the aquastat comes with the unit, but I might actually have one lying around. My first question is, will this be enough capacity?
We have one full bath with another 3/4 bath being built now. We have a dishwasher and a washing machine. I can get a 40 gallon superstore for $500 that is brand new. I already have a pump and I am assuming the aquastat comes with the unit, but I might actually have one lying around. My first question is, will this be enough capacity?
#2
What super stor is it?
You need to do the math..
This pdf shows a ss 35 and its GPH ratings at the bottom. For these ratings you need the min sized boiler they recommend and have it on priority...
http://www.htproducts.com/literature/lp-66.pdf
example 115f water with a 65f delta T.
Typical water from the ground is 50F. Heat it with 65f temp rise you get 115f water. Per the chart you get 152 GPH. Or about 2.5 GPM..
But you need the right size pump to get the 8gpm through the superstor, and the min size boiler.
page 4 here shows 53k btu boiler minimum for SS35. Page 7 shows 8 gpm pump needed.
http://www.htproducts.com/literature/lp-65.pdf
You need to pipe these with thier own pumps. Youll need flow controls, zone priority controls, etc.....
You need to do the math..
This pdf shows a ss 35 and its GPH ratings at the bottom. For these ratings you need the min sized boiler they recommend and have it on priority...
http://www.htproducts.com/literature/lp-66.pdf
example 115f water with a 65f delta T.
Typical water from the ground is 50F. Heat it with 65f temp rise you get 115f water. Per the chart you get 152 GPH. Or about 2.5 GPM..
But you need the right size pump to get the 8gpm through the superstor, and the min size boiler.
page 4 here shows 53k btu boiler minimum for SS35. Page 7 shows 8 gpm pump needed.
http://www.htproducts.com/literature/lp-65.pdf
You need to pipe these with thier own pumps. Youll need flow controls, zone priority controls, etc.....
#3
Member
Thread Starter
Lawrosa,
Thanks for the reply. Your answers are always helpful. I have asked for the model number it seems like there is only a 30 gallon and 45 gallon listed on HTP's website.
I have a Burnham MPO-IQ84. So I have 69k BTU to work with. I have the outdoor reset installed with DHW priority. There are provisions on the boiler to hook up a DHW circulator and the outdoor reset card looks like it has the hookup for the superstore aquastat. I have a brand new spare Taco 007 circulator, from the pump curve it looks like that would work?? Also the Burnham piping schematic shows no zone valve for the DHW loop just a circulator... Is this ok? On the heat side I have 3 zones, 1 pump and zone valves.
I think the worse case scenario would be running two baths back to back. The typical case is the kids let the water run for 20 min sometimes the drain is open. Then they sit in the tub and play for 20 min. Then the next one gets in.... My wife and I rarely take showers back to back.
So from the chart using the min boiler BTU and 2.5 GPM this would mean that the kids could run one bath continuously for 37.5 min (assuming 4 GPM at the tub). I am also just using the numbers for the SSC-35 until I find out what the model number is and know what the tank size actually is.
The listed recovery time is 10-13 minutes when sized properly. This seems a lot faster than what we have now.
Thanks for the help. As soon as I find out what the model number is i'll do some calcs and post them to see if you agree.
Thanks for the reply. Your answers are always helpful. I have asked for the model number it seems like there is only a 30 gallon and 45 gallon listed on HTP's website.
I have a Burnham MPO-IQ84. So I have 69k BTU to work with. I have the outdoor reset installed with DHW priority. There are provisions on the boiler to hook up a DHW circulator and the outdoor reset card looks like it has the hookup for the superstore aquastat. I have a brand new spare Taco 007 circulator, from the pump curve it looks like that would work?? Also the Burnham piping schematic shows no zone valve for the DHW loop just a circulator... Is this ok? On the heat side I have 3 zones, 1 pump and zone valves.
I think the worse case scenario would be running two baths back to back. The typical case is the kids let the water run for 20 min sometimes the drain is open. Then they sit in the tub and play for 20 min. Then the next one gets in.... My wife and I rarely take showers back to back.
So from the chart using the min boiler BTU and 2.5 GPM this would mean that the kids could run one bath continuously for 37.5 min (assuming 4 GPM at the tub). I am also just using the numbers for the SSC-35 until I find out what the model number is and know what the tank size actually is.
The listed recovery time is 10-13 minutes when sized properly. This seems a lot faster than what we have now.
Thanks for the help. As soon as I find out what the model number is i'll do some calcs and post them to see if you agree.
#4
The ss 35 is a 35 gal tank. You'll get 30 gal usable output. IMO this is enough.
Youll get real fast recovery.
I mean I would do it. For $500 bucks is not a bad deal. They can be found for $900 new. Is this a new unit?
Youll get real fast recovery.
I mean I would do it. For $500 bucks is not a bad deal. They can be found for $900 new. Is this a new unit?
#5
Member
Thread Starter
He says it's never been used. I just want to make sure that all the stuff I'll need for the install isn't super expensive. After buying the Boiler and the parts to install we don't have a ton of $$ left over for a hot water heater. I was going to limp along until next year but this seems like a really good deal.
#6
Figure 13b here..
https://file.ac/XxMmlp_okRY/MPO-IQ%20I%26O.pdf
Youll need 1" copper and fittings. ( I believe thats the SS in/out size)
Pump/valves
Check valve
The MPO has provisions for the indirect circ to make priority,,
You must pipe as shown. I dont know how challenging that may be. Depends on how the boiler is piped now..
Close spaced tees? Location of system circ and exp tank...etc etc
https://file.ac/XxMmlp_okRY/MPO-IQ%20I%26O.pdf
Youll need 1" copper and fittings. ( I believe thats the SS in/out size)
Pump/valves
Check valve
The MPO has provisions for the indirect circ to make priority,,
You must pipe as shown. I dont know how challenging that may be. Depends on how the boiler is piped now..
Close spaced tees? Location of system circ and exp tank...etc etc
#7
Member
Thread Starter
Here is the current piping.... I was thinking of removing the drain valve on top of the Tee just before the air seperator and putting a Tee so that the drain could still be put there. Then I could run from that new tee over to the superstore (it would be just about 5 feet away). On the return side I could replace the 90 after the union with a T. Then run from the T over to the outlet on the Superstore. I still have a 1 1/2" Full port valve that I didn't use that I could put to use here, then reduce it down to 1" copper after that. I would just need the copper pipe/fittings another valve and a check valve.

Last edited by hammerpe33; 05-16-17 at 10:50 AM.
#10
What type heat emmitters?
Do you really need the boiler bypass?
Do you really need the boiler bypass?
The MPO-IQ is designed to withstand thermal shock from
return water temperatures as low as 100°F, but prolonged
return temperatures of below 135°F can cause excessive
flue gas condensation and damage the boiler and/or venting
system.
Use a boiler bypass if the boiler is to be operated in a
system which has a large volume or excessive radiation
where low boiler water temperatures may be encountered
(i.e. converted gravity circulation system, etc.) The bypass
should be the same size as the supply and return lines with
valves located in the bypass and return line as illustrated
in Figures 13A and 13B in order to regulate water flow
for maintenance of higher boiler water temperature.
return water temperatures as low as 100°F, but prolonged
return temperatures of below 135°F can cause excessive
flue gas condensation and damage the boiler and/or venting
system.
Use a boiler bypass if the boiler is to be operated in a
system which has a large volume or excessive radiation
where low boiler water temperatures may be encountered
(i.e. converted gravity circulation system, etc.) The bypass
should be the same size as the supply and return lines with
valves located in the bypass and return line as illustrated
in Figures 13A and 13B in order to regulate water flow
for maintenance of higher boiler water temperature.
#11
Member
Thread Starter
Although I am not sure of the implications of not pumping away from the expansion tank.. The MPO shows the connection between exp tank and circ,,
Last edited by hammerpe33; 05-16-17 at 12:32 PM.
#12
Member
Thread Starter
What type heat emmitters?
Do you really need the boiler bypass?
Do you really need the boiler bypass?
#14
Member
Thread Starter
The indirect is a SSU45. I think this is too big for my boiler? I'm not sure. The literature for the SSU series is a little confusing to me. It has a reduced boiler size chart. I'm not sure if that chart is showing a first hour rating at 180F or what??
#16
1. its an ultra stainless tank.. No anode needed. ( I dont install these)
2. Buying on the street they are pricey. $500 for yours is a good price but,
3. They need 10gpm pump ( This pump ratings are only used to get the GPH ratings) Using other pumps will just reduce these #'s.
4.Its 292 GPH @ 115F water out of faucet. ( Thats with 180F boiler temp) Thats 4.8g GPM but you must meet all the criteria.
4.
Specs say 141 K boiler needed.. ( Thats why someone probably returned it..)
5. Your boiler is DOE 74K btu
So take that 292 and cut it in half.. Thats 146 GPH. Then with the 007 you will not get 10gpm I believe.
So then reduce the GPH more. Say 100 GPH. ( Just throwing that # out. I dont know the reduction) But that dictates 1.6 gpm..
So you see why us plumbers like the contenders?
We aim to make customers happy with unlimited hot water as best we can...
The ultra specs..
http://www.htproducts.com/literature/lp-83.pdf
2. Buying on the street they are pricey. $500 for yours is a good price but,
3. They need 10gpm pump ( This pump ratings are only used to get the GPH ratings) Using other pumps will just reduce these #'s.
4.Its 292 GPH @ 115F water out of faucet. ( Thats with 180F boiler temp) Thats 4.8g GPM but you must meet all the criteria.
4.

5. Your boiler is DOE 74K btu
So take that 292 and cut it in half.. Thats 146 GPH. Then with the 007 you will not get 10gpm I believe.
So then reduce the GPH more. Say 100 GPH. ( Just throwing that # out. I dont know the reduction) But that dictates 1.6 gpm..
So you see why us plumbers like the contenders?
We aim to make customers happy with unlimited hot water as best we can...
The ultra specs..
http://www.htproducts.com/literature/lp-83.pdf
#17
Member
Thread Starter
Well I guess it was worth a shot. By the time I got
a new pump I would be almost at the same price as a ssc35 and it wouldn't work as well. At least now I know more about sizing these. The ssc35 is pretty reasonably priced new so that's something I can consider...
Again thank you for all your help.
a new pump I would be almost at the same price as a ssc35 and it wouldn't work as well. At least now I know more about sizing these. The ssc35 is pretty reasonably priced new so that's something I can consider...
Again thank you for all your help.
Last edited by hammerpe33; 05-18-17 at 03:20 AM.
#18
Yeah I would go take a ride to boston and pick it up..
744 best price ive seen..
Superstor Contender, SSC-35, Glass Lined Indirect Water Heater
744 best price ive seen..
Superstor Contender, SSC-35, Glass Lined Indirect Water Heater
#19
Member
Thread Starter
Too funny, I just saw that this morning and figured out how long of a drive it would be.... I am going to jump on that.
#20
Member
Thread Starter
Yeah I would go take a ride to boston and pick it up..
744 best price ive seen..
Superstor Contender, SSC-35, Glass Lined Indirect Water Heater
744 best price ive seen..
Superstor Contender, SSC-35, Glass Lined Indirect Water Heater
#21
Member
Thread Starter
I got a hold of them and they are ordering the SSC-35 for me. I'll pick it up this week hopefully. I do have a question on the pipng schematics. In figure 13b on Burnhams schematic here shows a shutoff valve, circulator and union on the inlet side of the SSC-35. On the outlet this schematic shows, a union, shutoff valve and a check valve. I have zone valves and one circulator pump for the heat side. So I was planning on using this schematic.
The SSC Schematic shown here in figure 6 shows a backflow preventer then a circulator on the inlet side. Then there is a note that says if a backflow preventor is on the Cold Water Inlet to the contender then I need an expansion tank between the back flow preventer and the Contender.
I was planning on using the Burnham Schematic is that ok?
My current electric hot water heater has no expansion tank and no backflow preventer on it. Can I keep this configuration with no backflow preventer and no expansion tank?
The SSC Schematic shown here in figure 6 shows a backflow preventer then a circulator on the inlet side. Then there is a note that says if a backflow preventor is on the Cold Water Inlet to the contender then I need an expansion tank between the back flow preventer and the Contender.
I was planning on using the Burnham Schematic is that ok?
My current electric hot water heater has no expansion tank and no backflow preventer on it. Can I keep this configuration with no backflow preventer and no expansion tank?
#23
Just get an IFC for your pump. Cheaper then buying a check valve..
Taco Pumps IFC Kit - Taco Pumps IFC - Taco Pumps - SupplyHouse.com
Taco Pumps IFC Kit - Taco Pumps IFC - Taco Pumps - SupplyHouse.com
#24
Member
Thread Starter
Just get an IFC for your pump. Cheaper then buying a check valve..
Is there a PRV at the main water line to the home anywhere?
#25
Member
Thread Starter
I finally got this installed... Long story short, I decided to correct a lot of the crazy plumbing associated with the old water heater. So I put in a Manabloc. So there was a lot of leg work to do before I could get this installed. It is all working now. One issue I have is that the loop for the indirect doesnt go through the microbubble separator, So I put in a Hy-vent at the high point on a 90 that goes down to the pump. It works, I can hear air purging, but there still seems to be quite a bit of air in that loop. Over time it seems to be getting better. Should I put an air separator on this loop?? Also, what is the going opinion on mixing valves? Is it more efficient to run the tank at 140 (or higher) with a mixing valve or run it at 120 (like we are now) without one.
#26
I assume that tee that you tapped into for the indirect off the boiler is the high spot. If you still have that valve in there I would replace with a can vent.
But if you want to add a mico bubbler you could..
Also raising the psi in the boiler would promote air reduction..
Have you looked at the boiler pressure?
But if you want to add a mico bubbler you could..
Also raising the psi in the boiler would promote air reduction..
Have you looked at the boiler pressure?
#27
Member
Thread Starter
Here are some images of the piping. I think (you can tell me) the problem might be on the return side? I went up from the return on the superstor, then across then down to tie into the main system return. If any air gets trapped on this run i'm not entirely sure how it would easily get out. I guess eventually it could but seems like I made a mistake by going up from the super stor then back down again. The boiler is currently at 20 Psi.







Last edited by lawrosa; 08-21-17 at 09:45 AM. Reason: Images not attached properly / Mod note: Fixed images
#28
Looks like you have something brass down by the return union. Its upside down. Is that a scrubber?
I dont know if the hi vent you have now may be sucking air in becuase its on the suction side of pump..
I dont know if the hi vent you have now may be sucking air in becuase its on the suction side of pump..
#29
Member
Thread Starter
I dont know if the hi vent you have now may be sucking air in becuase its on the suction side of pump
Looks like you have something brass down by the return union. Its upside down. Is that a scrubber?
#31
Member
Thread Starter
Not sure what happened but I cant see the pics I posted anymore, can you see them?
Also, on the mixing valve for the indirect tank... What is your thoughts on that? Should I get a mixing valve and run the tank temp higher? Would that also keep the water temp more even? Right now I can detect a slight fluctuation in temp by the end of my shower (I have to adjust the knob a tiny bit).
Also, on the mixing valve for the indirect tank... What is your thoughts on that? Should I get a mixing valve and run the tank temp higher? Would that also keep the water temp more even? Right now I can detect a slight fluctuation in temp by the end of my shower (I have to adjust the knob a tiny bit).
#32
Member
Thread Starter
Many thanks for all the help. This is all in and working properly. I just installed another microbubble air separator. It was just going to be less time to do that. I did have one issue.. the thermostat went bad on the unit! It was covered under warranty. I went through FW Webb to get a new one and to do the warranty. It is just a lower thermostat that is used on electric tanks so I actually stole the one from my old tank to use while the new one was on it's way. We are a family of four and so far we have plenty of hot water.