In floor radiant floor heating, closed loop.

[scottransell]

I have a closed loop radiant floor heating system with it being attached to my Hot water demand system. The issue I have is that the floor heating keeps pressuring up and blowing out from the over pressure valve. They glycol keeps releasing into a bucket I placed and have about a inch in the bucket now after a month of the floor being placed on. I am not sure why the system keeps pressuring up. I have the system only in the basement so not going up any hills. Its a large system with a a seven zone manifold. The out going pressure is 20 psi and the incoming pressure is about 25psi with the tank set around 21psi. I am not sure if these pressures are good, or bad. The system works this way. If someone is having a shower the hot water demand shuts down the floor and goes to the shower, when it is finished it goes back to heating the floor. I am not sure if the glycol is low or has air pockets. Not exactly sure what is causing this over pressure to release. I am sure its because of the flipping from summer to winter mode, as in the summer I shut down the floor heat, but as soon as I increase the heat that is when I notice the over pressuring. Is this normal? If so at what point do you need to refill the lines as I have noticed that I have to crank the heat up more each year to get the floors to heat better. Thinking the glycol isn't running through it or lack of it.
Any advice would be appreciated, what to look at or try here would be much appreciated. the system is about twelve years old now, and the guy that built the system is no longer around to help or advise. thanks Scott

 

[Fitter30]

Floor heat doesn't need to more than 10 lbs under 100°with boiler and pumps off. Expansion tank pressure needs to be checked at the opposite piping end with a 50# tire gauge should be the same pressure as the system. If water comes out tank is bad and needs to be replaced. Air pressure can be added with tire pump. Water fill valve needs to be readjusted to 10lbs. Is the glycol boiler / chiller grade? Could post this question in the boiler section.

 

[Sponsor]

 

[John Gayewski]

To me it sounds like you have your expansion tank isolated from the system with a check valve somewhere or your expansion tank is bad. To figure this out you'd need to post a diagram of exactly how your piping and system components are arranged or a picture including the piping and components.

Do you have a makeup water system installed with a prv to automatically refill the system?

 

[scottransell]

so this is my system working right now

 

[scottransell]

To me it sounds like you have your expansion tank isolated from the system with a check valve somewhere or your expansion tank is bad. To figure this out you'd need to post a diagram of exactly how your piping and system components are arranged or a picture including the piping and components.

Do you have a makeup water system installed with a prv to automatically refill the system?

No make up water installed, its a diluted glycol system, Ive attached pictures so you can see they system thanks

 

[Fitter30]

NTI boiler model number? Never seen a boiler piped like that with a bypass hose and where the relief valve is a bypass back into boiler. Never seen the brass fittings feeding the zones what brand are they and what their called? Ex tank can't tell where its piped into.

 

[scottransell]

so this is my system working right now

 

[scottransell]

NTI boiler model number? Never seen a boiler piped like that with a bypass hose and where the relief valve is a bypass back into boiler. Never seen the brass fittings feeding the zones what brand are they and what their called? Ex tank can't tell where its piped into.

I attached more pictures for you can look at and see the system better. thanks for responding back.

 

[Fitter30]

Need to know about the brass fittings feeding the zones never seen one. For both of them. Couldn't read the model is it ti200? Ti boiler is different with plate heat exchanger for dhw. What brand is the micro bubbler air bleed?
Your not piped like page 37. Boiler doesn't have hydraulic separation back to back tees connecting primary loop to secondary loop. Expansion tank needs to be moved in the secondary loop. Relief valve opening when boiler goes from dhw to heat what happens to the boiler water temp for a few seconds probably goes up system pressure follows. 20 lbs of system pressure = 46.2'.
10 lb system pressure is more than i need with boiler and pumps off water under 100°.

 

[scottransell]

Need to know about the brass fittings feeding the zones never seen one. For both of them. Couldn't read the model is it ti200? Ti boiler is different with plate heat exchanger for dhw. What brand is the micro bubbler air bleed?

It is a Ti200 and the zones header is a heat link header, not sure what you are asking about the micro bubbler, the tank is a Flex 2 pro. Ive had this system for twelve years and the last few years is when I started noticing the over pressure. that is why I am wondering if the system has air or low on the poly glycol

 

[Fitter30]

Did water come out of the ex tank air valve when depressed? What brand and % is the glycol or what temperature is the protection down to so i can work backwards for the %.

 

[John Gayewski]

I haven't seen a puking setup like this. Where did the supply/return fitting come from? I'm guessing that's some kind of molded type of diverter tee. I also don't see how the bypass on the suction side of the pump isn't short cycling the radiant loop (edit from a distention angle I see that rubber hose isn't a bypass).

Do you have a link for the fitting the radiant loop is hooked to? The fitting that handles the supply/return/ and the primary loop apparently? This must be done non USA or at least new non standard fitting from what is normally used.

 

[Fitter30]

I haven't seen a puking setup like this. Where did the supply/return fitting come from? I'm guessing that's some kind of molded type of diverter tee. I also don't see how the bypass on the suction side of the pump isn't short cycling the radiant loop (edit from a distention angle I see that rubber hose isn't a bypass).

Do you have a link for the fitting the radiant loop is hooked to? The fitting that handles the supply/return/ and the primary loop apparently? This must be done non USA or at least new non standard fitting from what is normally used.

Two of us want to know about the brass fittings. Any number or name on them or where they were purchased.