Hello, we have a infloor radiant heat system that lost pressure recently. Have having the installer out he determined that the fluid (which was almost brown in color) needed replaced and he would add rust inhibitor. My question is this normal after only 2 years (two winters) of use? He said that he filled with high quality water/glycol mixture when he first filled system.
Radiant floor heat (closed system) needs fluid replaced after 24 months
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Well, obviously there's a leak! Also, air is somehow getting into the system, as you shouldn't have rust in the fluid--an air free, closed loop system shouldn't rust and you should be able to get away with a cast iron body circulator pump, not the more costly stainless steel or bronze which are required for potable water systems. Your system should have an air eliminator as well as expansion tank. You should not lose fluid.
I had a snowmelt system with 28 gallons of custom-blended glycol, two circulator pumps (though I opted for stainless and bronze simply because of availability and longevity not because they were necessary) at my home. That was fired with a 200K BTU heater. I also had a carwash with a similar system, but 3x the size in nearly every dimension. Never had a leak; in 10 years while I owned the home we still had all the fluid. So, no--losing fluid in two years of operation isn't normal.
However as all the PEX was buried in concrete, leak detection was costly and invasive; we thought we might have at one time, but we didn't. One method involved purging the system of fluid, and filling with compressed air and searching for a leak with sound. Another method involved pressurizing with helium or some other gas and using a sophisticated sniffer to detect the approximate location. Not easy, not cheap and then there's the repair...
I had a snowmelt system with 28 gallons of custom-blended glycol, two circulator pumps (though I opted for stainless and bronze simply because of availability and longevity not because they were necessary) at my home. That was fired with a 200K BTU heater. I also had a carwash with a similar system, but 3x the size in nearly every dimension. Never had a leak; in 10 years while I owned the home we still had all the fluid. So, no--losing fluid in two years of operation isn't normal.
However as all the PEX was buried in concrete, leak detection was costly and invasive; we thought we might have at one time, but we didn't. One method involved purging the system of fluid, and filling with compressed air and searching for a leak with sound. Another method involved pressurizing with helium or some other gas and using a sophisticated sniffer to detect the approximate location. Not easy, not cheap and then there's the repair...
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Check for a collapsed air bladder in the expansion tank
and leaks.
in a heating system you need to check for leaks with the boiler off, water cool and pump running
hot water will cause piping to expand, hiding a leak, then as system cools leak appears
and leaks.
in a heating system you need to check for leaks with the boiler off, water cool and pump running
hot water will cause piping to expand, hiding a leak, then as system cools leak appears
Well it depends on where it is! If you are lucky it's somewhere in your heating system, not the tubing. Cracks happen and develop over time and get worse as heat causes pieces and parts to expand and contract.
I've had electrical shorts develop in low-voltage wire over a period of years due to a nail placed in the wrong place. I've had window seals break by improper framing, and years of expansion and contraction against a nail caused a break. So, stuff happens.
I've had electrical shorts develop in low-voltage wire over a period of years due to a nail placed in the wrong place. I've had window seals break by improper framing, and years of expansion and contraction against a nail caused a break. So, stuff happens.
fixitron
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The problem, or actually the symptom, is a loss of pressure in a heating system. What we don't know is how the loss in pressure was manifested and detected, whether the pressure gauge used is accurately reading the pressure, how much the pressure changed and how much the concentration of glycol changed. The heating system should have a minimum pressure maintained by the feed pressure regulator. We also don't know what the conditions were when the contractor filled the system 2 years ago. Was it an existing or a new system? Did he flush and clean the system before adding the glycol? Are there any signs of the relief valve lifting?
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