Which Boiler do I need?

[silvermonte]

Heres the back story, self built place. 80'x50' post frame building, 2500 of it is garage and 1500 of it is house, the place is tall enough for a second floor but for now its just a single floor. The concrete slab is just poured on grade, has r20 pink board insulation all the way around the slab 3' down and r10 under the concrete. The walls are r29 and the attic is r60 and Im located in east central Iowa. The garage has 2 zones and the house has its own zone, id like to plan ahead and have the option for a 4th zone for the second floor when that becomes a reality.

Editing for more information- 1/2" pex and i tried really hard to make all the lines as close to 290', the one that is off the most is just 10' shorter compared to the others. There are 2 zones in the garage with 5 runs apiece, and the house has 5 runs for the 3 zones. If a 4th zone went in for the second floor it would probably only have 4 runs at most. The house has 2 1/2 baths in it.

Heres where I would like some help. Are there better options for the money then the items listed? I have propane and electric is just silly expensive where im at so thats not an option really.

boiler- https://www.menards.com/main/plumbi...ler/rmcbh-l199i/p-1642874299838873-c-8519.htm

https://media.richmondwaterheaters.com/blobazrheem/wp-content/uploads/sites/43/2023/07/T-TK-RMCBH-L-Rev-1-Richmond-Combi-ssindd.pdf

Panels- https://www.menards.com/main/plumbi...ete-system/6959775/p-1471978652594-c-8521.htm

HS1T4ZPMP - 1 Temp, 4 Zone by Pump Zoning Panel

This Zoning Panel works with various Master Panels and is utilized when more than one thermostat zones is required in the system. The Zone Panel extracts the processed heated fluid from the Master Panel and redistributes to each thermostat emitter zone. The emitter circuit has hydraulic...

www.hydro-smart.com

https://www.hydro-smart.com/products/hsps120lt?_pos=1&_psq=hsps&_psid=70f6e9ef1&_ss=e

 

[fitter30]

Size of pex ,lenght of loops and number of them. Mernards thinks im a bot.

 

[kj_mustang]

Boiler spec write up is not very thorough. Since it is a Combi boiler you really need to know the max DHW flow rate and how much DHW flow you and the house occupants potentially will be using at the same time.

 

[Sumboodie]

Need to do a manual J calc.

Boiler link doesnt work, says I need security.

 

[Sumboodie]

Boiler spec write up is not very thorough. Since it is a Combi boiler you really need to know the max DHW flow rate and how much DHW flow you and the house occupants potentially will be using at the same time.

And cold water temp.

 

[kj_mustang]

Found the boiler info on their website. These are made by Rheem. 199,000 BTU model has a 5 gallon a minute DHW flow rate at 67 degree rise.
https://files.myrheem.com/webpartners/ProductDocuments/BB95E591-FC47-408F-921F-62E12F00A4DD.pdf

 

[PoorUB]

How many feet of tubing? Roughly 30 BTU per foot, so no sense in putting i a larger boiler than the tubing can handle.

Need to do a manual J calc.

Yes and no. The manual J might come out higher than the floor tubing can use. If the building needs 100,000 BTU, but he has only 50,000 BTU of tubing a larger boiler is a waste.

 

[silvermonte]

How many feet of tubing? Roughly 30 BTU per foot, so no sense in putting i a larger boiler than the tubing can handle.


Yes and no. The manual J might come out higher than the floor tubing can use. If the building needs 100,000 BTU, but he has only 50,000 BTU of tubing a larger boiler is a waste.

I have roughly 4350' of 1/2" tubing in the floor between the 3 zones.

 

[silvermonte]

Size of pex ,lenght of loops and number of them. Mernards thinks im a bot.

1/2" pex, roughly 290' apiece and 15 runs total , 2 zones in the garage and one in the house that are 5 runs apiece.

 

[silvermonte]

Boiler spec write up is not very thorough. Since it is a Combi boiler you really need to know the max DHW flow rate and how much DHW flow you and the house occupants potentially will be using at the same time.

I put a new link up that hopefully helps.

 

[PoorUB]

I have roughly 4350' of 1/2" tubing in the floor between the 3 zones.

4350 feet x 30 BTU gets you 130,000 BTU. So for the existing you need 130,000 BTU. Then add any anticipated additions, or the second floor in your case. Also you 50x80 comes to 4,000 sqft. Most of the time, for floor tubing in normal situations we always ended up with I foot of tubing per 1 sqft of floor, 4250 feet is a bit more, but pretty close to the 1 ft per 1 sqft. So if the anticipated second floor is 1,000 sqft, you will need another 30,000 BTU. In reality you probably don't need that much heat for the space. the 199,000 boiler is not out of line, 150,000 would probably do it.

Are you looking for a combi boiler, for domestic hot water too? If you are then you will want to size it for your domestic hot water requirements.

 

[silvermonte]

Are you looking for a combi boiler, for domestic hot water too? If you are then you will want to size it for your domestic hot water requirements

That particular boiler is a combi boiler, which I wanted for domestic use also, if its feasible. I have room for a standard water heater, but why use one if I can get away with a combi boiler and call it a day. Im out of my element with this stuff which is why Im asking for suggestions. The house would be 2 1/2 bathrooms and a 4 bedroom house. I dont know what a standard amount for domestic water would use.

 

[fitter30]

1/2" pex, roughly 290' apiece and 15 runs total , 2 zones in the garage and one in the house that are 5 runs apiece.

147,900 btu's total
each zone 49,300 btu's
Flow through each loop 1 gpm
Head .03X300= .9' then add 2' for piping around the boiler.
In the house any wood floor coverings or vinyl check with flooring manufacturer for temp limit for water temp most 80-85°. Boiler glycol 30% minimum 50% max. 30Glycol manufacturers list total freeze protection and slush. Slush might have to go to web site or call customer service.