Radiant heat system, shutdown for summer?

[NateS]

My house is heated by a radiant heat system that uses a natural gas water heater. Apparently the hot water circulated through the radiant heat system is also the hot water that we get from the taps. I'd like to shutdown the radiant heat during the summer because it seems silly to pump hot water through the walls.

It looks to me that the water comes from the water heater, through a pump on a timer, through a valve with a red handle, then splits into many tubes that go to registers in the house, then comes back through tubes and joins into one pipe, through a valve with a blue handle, and back to the hot water tank. There are some other pipes for the house's tap water that are connected to the radiant heat system on its way back to the tank, but I don't think I could accurately describe them. I can take a picture if needed.

The only way I can see to disable the radiant system is to turn off the valve before the pipe splits into tubes and is distributed throughout the house, and to turn off the valve after the return tubes combine back into a pipe. I would also have to unplug the pump that is on a timer, so that it doesn't burn up pumping against a closed valve. I think this would cause the water to sit in the tubes in the walls throughout the house. Is this ok? I'm worried something might grow and contaminate the tap water. How often would I have to open the valves and run the pump to keep this from happening?

Is there any other way to disable the system?

 

[NateS]

No ideas on this?

 

[Red'n'WhiteRebel]

Sometimes you just have to get pro help. IMO this is 1 of those times. Find someone in your area that designs and installs these systems and ask. I don't think they would want $$ for that.

 

[shift2sixth]

If I'm reading you correctly, you are concerned with sitting water in the heating system contaminating your tap water?
If so, you have nothing to worry about. These are two different systems and are separated by a check valve that only flows water in one direction. There is no need to close any valves unless you plan to service the system for some reason.
Hope this helps.

 

[NateS]

Thanks for the replies guys.

Yes, you got it shift, I'm worried if water in the heating system sits all summer it may contaminate the drinking water when we turn it back on for winter. When we bought the house they said it was all one system. I guess it is a good idea to check with a plumber, hopefully I can do it over the phone!

Thanks for the advice!!!

 

[6t7gto]

Maybe ask here:

http://www.terrylove.com/forums/

david

 

[haggis]

I installed my own whole house radiant heat system last year. Mine is all one system. You need to keep the valves open to prevent stagnation. If your system is a standard setup, cold water from the city does not go directly to the water heater. It will go through the pex tubing in the floor first. This is to prevent stagnation when the pump is not running in the summer time. Every time you use hot water for a shower, etc, the cold water that fills the water heater will circulate through the floor first. Hope this makes sense.

The one way valve you have (if like mine) is to prevent the cold water from going directly into the water heater, it forces it to go through the floor, or return pipe. I adjust my thermostat down to 50 degrees in the summer time, this prevents the pump from every having to turn on.

Here's a pic of my system

 

[shift2sixth]

Apparently there is more than one type of system, and probably depends on who did the installation. They seem to range from simple to very complex. I will be making a few upgrades to my system, one of which is adding a spiral vent to keep the air bubbles out.
From my research I have concluded that your water supply and heating circuits should be kept seperate by a check valve(s). It is my understanding that this check valve also regulates the pressure at which the heating loop operates. Your city water supply should be somewhere in the 60 psi range. The heating loop should only be 15 psi according to my source. The two systems are supposed to use different types of pex tubing as well. If you have copper tubing, this is not an issue.
I think we all agree that water supply should not be contaminated by stagnant heating loop water EVER, and knowledge of your system is a good thing!

 

[kbs2244]

There is no way a professionally installed system is going to send domestic hot water through the heating system.
They have to be separate systems.
Get a pro to show you what you have, and maybe fix it up to code if it isn’t.

 

[RickP330]

My Radiant heat is totally isolated from the rest of the house heating and the DHW. I run a Heat Exchanger to heat the floor coils from the burner. I run my coils around 5psi and seperate it because it is an old installation that has a slight leak and I don't want make up water filling my burner constantly. Your DHW should be totally seperate from your heating zones. My installation is around 50 years old and I never had a problem with stagnant water.
RickP

 

[MyDomain]

I agree, if your system is pumping dhw through your floor it needs to be redesigned using flat plate exchangers to isolate the two systems. You can check out www . hvac-talk . com but the pros can be sensitive when dealing with h.o.'s.