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Nov
I have a hot water recirc system with a small grundfos pump on the hot water return line. Backpressure for example insufficient relief of pressure in a vessel where water is heated.
You do need an expansion control device if your incoming water has a check valve or a PR valve installed.
Hot water backflow into cold. Hot water can backflow into cold water due to a misaligned shutoff valve damaged check valve high water pressure or high temperature. Its recommended to install an expansion valve and cartridge to fix the problem. The one thing you dont want to do is leave the problem as-is.
The situation is going to get worse and the water will become difficult to use due to the hot. When theres a high demand for cold water hot water is flowing back up the cold supply cold in and hot out are both on top of HW tank and mixing with the cold supply. I first noticed the longer you ran a cold tap the warmer the water gotand verified what was happening by the cold inlet pipe on the tank becoming hot very hot and the heat travels right up to the T with the cold pipe.
If open to both hot and col the cold will partly come out of the faucet into the sink and partly flow into the empty hot water lines. Hot water backing up into cold side of hot water tank. Then my son enters the bathroom and turns on the cold water.
Hot water backflow - m Re. Iaposm having an issue with hot water backing up into the supply side of. Hot water backflow into cold supply.
I have a hot water recirc system with a small grundfos pump on the hot water return line. We also have 7 single lever mixing water valves on sinks and tubs. Within the past few months the cold water tap has been dispensing cold water for about 5 seconds then hot water for about twenty seconds and then cold.
You do need an expansion control device if your incoming water has a check valve or a PR valve installed. A 50 Gallon hot water tank at normal temperatures uses a 2 gallon expansion tank. It should be installed on the cold water and make sure you read the installation instructions.
Backflow is not good for a hot or cold water system. The cause is can be high pressure high temperatures defective check valve or a miss applied shutoff valve. The effect is still in your case allowing hot water to backup into your cold water supply.
In short the hot water tank continuously overflows up into the cold water tank while the hot water is being heated. This happens to the point that if were heating the water for a while it will take the cold water tank up to the overflow level and then starts to drip outside. This problem is caused by a term called a cross conection by leaving tohe cold on isolating the hot.
Water is flowing to the other fixture as the second fixture is tied into the supply line before the valve you turned off now having a 2 handle faucet opening only 1 tap namely the hot nothing turn off the hot turn on cold water flows open both taps and water will flow through and feed. It sounds like the cold water feed is not at equal pressure with the hot water feed. This is normally caused by a poor installation of a shower as the hot and cold to a shower if tanked hot water should be equal pressure.
If its a shower run from a combination boiler the chances are the thermostatic cartridge in the shower is faulty. The last 6 feet of the return line is left uninsulated - this temp difference causes the water to cool become more dense then the water in the tank and fall pushing water out the top of the hot loop - I never goes into the cold because it would always have less pressure - the hot and return are slightly out of balance thus fluw. Anonymous User Yes it happened before the hot water heater.
If you run the hot water out to cold then shut off the hot. Do you wonder why does hot. Httpsamznto2Z0CrdyAre you experiencing a hot cold water crossover and suspect that you have water heater heat trap problems.
Sizing The Therm-X-Trol Potable Water Expansion Tank Backflow Preventer Expanded Water 1400 Division Road West Warwick RI 02893 T. The backflow preventer will not allow water to flow back to the supply. Most single handle faucets showers will leak over from cold to hot or from hot to cold during use if they arent set at the absolute maxmin setting.
To prevent this try turning off the local hot water valve at each single handle faucetshower. Thermal Expansion Hot Water Heater Concerns DHHR. The water heater unlike the hot water boiler system uses a continuous supply of fresh water.
As water is heated installed with or without a water meter the backflow preventer becomes an effective non-return barrier making the system closed. Backflow is caused by a difference in pressure and may occur due to. Backsiphonage the supply pressure is less than the downstream pressure allowing water to be pushed in the wrong direction.
Backpressure for example insufficient relief of pressure in a vessel where water is heated. That is of coursed caused by something crossing over from the cold side. Assuming he does not have a recirc pump then when the water heater is fully restored the crossover mode will still be cold INTO the hot side.
This is due to the slight ΔP caused by the water flowing through the wh. Jimbo Dec 20 2011. Replace the cold water shut off valve and continue the test.
If the water turns COLD you have cold water crossing over to the hot water plumbing system. To locate the cross-over first shut off the hose bib service valves to the laundry washer. If the water stops flowing at your hot faucet the washing machine mixing valve is causing the.