New old system makeover.

cnmdesign

*Designed and installed a new radiant system three years ago with all the best bells and whistles. It sets in my mechanical room, un-commissioned and ready to be dismantled and updated. Heated whole house upstairs and down using a 20K open log gas fire place in basement. Hit design day 5 nights in three winters and the temp in the house dropped to 61. Most of the time, the kitchen at the top of the stairs stayed around 68-71. Back bedroom down the hall stayed around 64 put was backed up with an electric heater with thermostat control and ceiling fan to keep heat off ceiling. Live in SE Ohio.

Question 1.

Can I use my new unused K2 boiler till it carps out, for DHW heating only? Way over kill, but is better than junking it. It will be connected to my new unused Burnham 50 gal. stoned lined, Alliance indirect hot water heater. Will just hook up directly using boilers circ pump and internal thermostat to keep the system at temp. Best I can figure, it should work like a buffer tank operation. With the tank being stone lined and heated to 180 degrees, using mixing valve, it should only cycle two or three times a day, never run out of hot water and last forever. Or not.

Question 2.

Yes, Maybe, He## No ?

*Home is a 1650 sq/ft first floor, 1650 basement, ranch with R60 attic, R19+ walls and R13 in walls in basement . Will be placing pex al pex in ceiling using information from these two links:

https://www.pmmag.com/ext/resources/PM/2014/June/016-020-0614-Siggy.pdf
https://www.jlconline.com/how-to/hvac/installing-a-radiant-wall_o

*Heat loss is figured at 24,500 BTU/ph. Water temp required will be somewhere between 95 and 110.

*Each room will have it's own radiator in ceiling controlled by a Caleffi TRV on a straight connector located in a box in the wall near light switch.

*System water will be heated by a natural gas absorption heat pump: (information only)

https://www.energy.gov/energysaver/heat-pump-systems/absorption-heat-pumps
https://www.robur.com/heat_pumps/gas_absorption_heat_pump_for_homes_k18
https://www.energy.gov/eere/buildings/downloads/absorption-heat-pump-water-heater-0

Or some kind of air to water heat pump.

*Circulation will be handled by my new unused Alpha2 15-55 ECM pump (originally designed for TRV systems) located just after my new unused Caleffi SEP4 4-n-1 hydraulic separator.

*Manifold will be .75 pex al pex run up to and down the middle of the attic for supply to ceilings and all returns will run from ceiling, through TVRs in wall box near light switch and back to return manifold in mechanical room.

*Would it be better to have all the runs start and end at the TRVs on the manifold in mechanical so there are no connection in wall or ceiling to leak?

Hope to end up with the basic of basic systems, easy to run, maintain and pretty much Bulletproof.
(no bells, whistles, control boxes, zone valves, zone pumps, flow regulators other than TRVs, thermostats)

What's missing or will not work?

Thanks

mattmia2

https://www.caleffi.com/usa/en-us/technical-magazine

cnmdesign

mattmia2 said:

https://www.caleffi.com/usa/en-us/technical-magazine

Thanks. Avid follower of Caleffi, will be watching. I have read and watched everything they have at least twice.

STEVEusaPA

Some pics?

cnmdesign

STEVEusaPA said:

Some pics?

Don't have a system yet to take pics of. Was bouncing this idea first before I put it together.

cnmdesign

Here is a pic of the system I'm going to modify.

Please be kind.

Jamie Hall

Eek. Well, I don't see any big leaks... that's good!

EzzyT

Wow that’s some of the worst piping I’ve ever seen

EBEBRATT-Ed

Agree with @EzzyT

The word modification is an understatement in this case

EzzyT

Your looking at a complete repipe. Rip that all out throw it all way and start from scratch.
Might be able to salvage the pumps and expansion tank.
Is that an electric water heater sitting below the combi unit?

HVACNUT

It looks like a rainbow sneezed.

What's that on the Taco relay? I hope that outlet is GFCI protected.

Larry Weingarten

Hi @cnmdesign , A thought. when you redo this, consider using bend supports with the PEX, rather than 90s. You'll get nearly no pressure drop that way. As plumbers, we've been trained to run things straight and square, but that isn't always the best for flow, particularly with modern materials. The trick is to get good flow without making the system look like spaghetti

Yours, Larry

mattmia2

Larry Weingarten said:

Hi @cnmdesign , A thought. when you redo this, consider using bend supports with the PEX, rather than 90s. You'll get nearly no pressure drop that way. As plumbers, we've been trained to run things straight and square, but that isn't always the best for flow, particularly with modern materials. The trick is to get good flow without making the system look like spaghetti

Yours, Larry

I'd make up the near boiler piping in copper and just attach the pex that runs to the building to adapters where it comes out of the wall. It will be much neater and probably cost less than all the pex fittings, especially if it is mostly 1/2" and 3/4" and you use sweat fittings. As much as possible thing about running piping horizontally and teeing of where it needs to connect to the building.

SuperTech

I also would definitely do all the near boiler piping in copper and use the pex only for the distribution piping. I like to insulate everything as well. You definitely have some work to do there, but at least you have some good components to reuse.

pecmsg

The soldering skills are about as bad as the pex!

JackW

Hard for me to tell but it looks like you have two zone system, that's what I have in my Morton building. I included a couple of pictures of the rebuild I did last year with the help of the great people on this site. If it helps you any you are more then welcome to copy all or part of my design. If you have any questions feel free to ask, if I can't answer them I know someone on here will. Good luck.