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[jared]

In the beginning stages of a new home construction, just picked up the underground pex from the boiler to the house (Buying a central boiler 5036) I have seen a bunch of diagram's on how I should set my system up but they are all different. I plan on having help from a local plumber when it gets time to do the hook ups but any advise on how the system should lay out would be appreciated.

Will have to radiant floor zones (Garage and basement)
Will be hooking system up with the furnace and the hot water heater (Propane both)

I know I will need a pump at the furnace then go to a themostatic valve, Do I go right to the hot water heater the furnace and then the manifolds for  the radiant heat(s). Will I need a second pump (zoning)?

Again any help would be welcome I am hoping the plumber will know more about this than I do but I want to at least have a decent knowledge about its for future repairs and adj. Thanks Jared from WI

[Scott7m]

Most plumbers would be totally lost in a situation like that

I would put in a header system.  Off of the header I would put a pump that would be turned on when whatever zone if was called for heat.

So yea you'll have a main pump, and depending on how many zones whether it be radiant, forced air, or whatever, each would require its own small pump to pull from the header.  Your water plate or side arm would be on the main loop with the header.    That's the best, most efficient way to do this, it will work great and be very comfortable.  But good luck cause most general plumbers and hvac folks I've seen would just stand and shake there heads at this lol...   

If you want to call me to discuss it feel free, I can point you in the right direction, you want to do this right the first time

[jared]

Ok great thinking scott.... would it be to much of me to ask for a simple diagram of what you were thinking?
 

[Scott7m]

I could yes, and will, but call if u want so I can explain how it works and the benefits of doing it this way

I can tell you a thing or two id have them to do on your regukar hvac system as well that would make the home more comfortable and healthier as well, most dont do it but man its night and day difference

[RSI]

If I were doing it I would just run to the water heater, then to the furnace and back out.
Then for the floor heat, I would do a secondary loop that could me put into the main loop wherever is most convenient. To make a secondary loop, just put two tees as close together as possible.

For the floor heat you will need a pump and mixing valve. It will only take enough water out of the main loop to keep the floor heat at the temperature that the mixing valve it set at.

If you plan on having separate manifolds for the garage and basement, you will need a pump and mixing valve for each. Otherwise, you could run the floor loops for both to the same but you won't have as much control over the temperate for each.

Also, for the garage you may want to consider isolating and pressurizing it and using antifreeze so you don't have to worry about the pipes near the overhead door freezing. If you pressurize it you would use a heat exchanger instead of the two tees. A 20 or 30 plate would be sufficient.

If you do pressurize it, I would go ahead and put the basement on the same system.

[slimjim]

May I make a suggestion, pressurize and anti freeze the garage loop especially if it is radiant in floor or you will freeze up sooner or later and then you have a big problem on your hands

[jared]

I like the idea ( and understand ) why you would want  to isolated the radiant from the rest but how do you isolate the two systems (radiant and furnace/water heater) and how do you pressurize it? isn't it considered pressurized already. sorry for the stupid questions.  jared

[RSI]

You use a water to water heat exchanger.
You will also need an expansion tank on the pressurized side.

Most outdoor boilers aren't pressurized. They just have an overflow pipe.

[jared]

RSi, Ok got it, how do I determine how large of a water to water heat exchanger I should use?
 

[RSI]

For in floor heat a 20 or 30 plate is plenty.

[slimjim]

Personnally with the prices of plate exchangers being what they are I would go big just to buy more time as they will eventually plug up from sediment, of course they can be set up to rinse them out with acid without taking them off if you choose to set it up that way. That is a good question for some of you guys, have you ever had any issues with plugging up, we have up here, lots of farmland and minerals in the water.

[Scott7m]

Personnally with the prices of plate exchangers being what they are I would go big just to buy more time as they will eventually plug up from sediment, of course they can be set up to rinse them out with acid without taking them off if you choose to set it up that way. That is a good question for some of you guys, have you ever had any issues with plugging up, we have up here, lots of farmland and minerals in the water.

No not really

But clr will clean them out... 

I haven't seen any issues out of them personally tho

[slimjim]

I now simply put a boiler drain on each port of the heat exchanger followed by a ball valve which allows me to isolate the system and pump acid or CLR through the heat exchanger with my evac pump, good as new in about 15 minutes and you dont need any wrenches

[jared]

Great info guys, here is a couple questions I have regarding the pressurized side of the system.

1 Do I tie the heat exchanger  for the pressurized system in before or after the hot water heater/Furnace

2 How do I control the two zones for the radiant floor heat(pressurized) system?

3 What components do I need on the pressurized system, I know I will need and expansion tank, and probably a pump and manifolds for the radiant.

4 My radiant 1/2 floor lines will becoming through the wall above the manifolds because of the basement how will that get plumbed into the manifold?

[slimjim]

#1 is the garage attatched, if so then come off the gas boiler to the heat exchanger, if it is a wall hung on demand gas boiler you will need to plumb primary secondary and inject from the gas boiler into the main loop, if the garage is not attatched I would come directly off the wood boiler to a plate exchanger in the back of the wood boiler and pressurize with anti freeze from that point. #2 controlling the heat zones is easy with a circulator relay, Taco makes a very good relay from 1 to 6 zones (501---506) I forgot #3 be right back!