Owb temp for sidearm

[farmking]

What are some of you running your owb temps at when going to your sidearm? I can only run about 165-170 because if I go any higher my relief valve lets go. I bought a new valve thinking maybe I had a bad one but it does the same thing.

 

[Mister Twister]

I had the same problem and I was not blowing off because of temp it was because of pressure. I did not believe I had that kind of pressure build up until I put a gauge in the line. Do you have an expansion tank installed? I actually had a bad pressure regulator from the water company it creeped up to over 100 psi. Our showers felt great and it happened gradually so we got used to it. Make sure you check pressure you may be surprised.

 

[ktm rider]

SO I'm guessing you both have a pressureized OWB's.

 

[Mister Twister]

No mine is a non pressurized system as are most.

 

[rx7145]

I run about 180*. Check you water pressure sounds too high.

 

[farmking]

I have a pressure regulator coming in from my main line. What is the correct way to adjust the pressure, with the faucet on or off? With it off I'm running 85psi on the gauge, with it on I'm running 40psi. My Owb is also non pressurized.

 

[Mister Twister]

The way I would check is to watch the gauge with all the faucets off and when the water in the hot water tank is heating. The water will expand and that is probably when your problem is occurring. That is when the max pressure in your system will be reached. That is how I found my problem. I would go down in the basement and see there was water under the T&P valve but never seen it actually blow off. Heres another tell tale sign.After the system sits for a while and the hot water tank cycled you can see when you first crack a faucet the pressure is high for a few seconds and then reduces a bit.

Good luck

 

[oneoldbanjo]

Do you have an expansion tank in your water system? If you have a pressure regulator it acts like a check valve and will not let any water flow back out to the water service line. When your OWB sidearm heats up the water it expands and needs someplace to expand to - the expansion tank give the system some relief....and is necessary whenever you put a pressure reduction valve in your house (or in some places the reduction valve is built into the meter pit to protect the water meter).

 

[Mister Twister]

+1 I asked that question earlier you are absolutely correct I experienced that first hand.

 

[farmking]

No expansion tank, I guess that's what the problem is. At what location do you install it at? Thanks for all your help!

 

[oneoldbanjo]

My expansion tank is located between the pressure reduction valve and the water heater inlet. My tank is attached at a 3/4" copper tee with a threaded fitting for the expansion tank, and it is located in the line a few feet prior to the water heater.

 

[Mister Twister]

Mine is setup about the same. Location is not critical just somewhere between your water meter/well pump and hot water tank. Watts even makes a pressure relief device for your toilet tank to do the same thing. I purchased my expansion tank from Lowe's I beleive for around 30 bucks. I am sure you will be happy with the results just set the pressure in the baffle to your relief valve pressure (mine is 65 psi) or pump cut-out pressure if you have a well.

 

[Geez]

I had the same problem and I was not blowing off because of temp it was because of pressure. I did not believe I had that kind of pressure build up until I put a gauge in the line. Do you have an expansion tank installed? I actually had a bad pressure regulator from the water company it creeped up to over 100 psi. Our showers felt great and it happened gradually so we got used to it. Make sure you check pressure you may be surprised.

Something doesn't sound right here. I'm not a plumber or steamfitter so maybe someone can 'splain it to me? The sidearm is just a heat exchanger and boiler water doesn't mingle with the potable water. Also Most OWB's are non pressurized units so how can the potable water system be running higher pressure, even if there WAS some pressure from the OWB? Or are we talking pressure in the potable water from the higher temps?

 

[Mister Twister]

Something doesn't sound right here. I'm not a plumber or steamfitter so maybe someone can 'splain it to me? The sidearm is just a heat exchanger and boiler water doesn't mingle with the potable water. Also Most OWB's are non pressurized units so how can the potable water system be running higher pressure, even if there WAS some pressure from the OWB? Or are we talking pressure in the potable water from the higher temps?

Yes the pressure is in the potable water you are on the same page.

 

[mimilkman1]

I am running a CB 5036 with a sidearm exchanger and have never had this problem. I guess the pressure from my pressure tank isn't high enough to cause this. I have had increased pressure a couple of times, but that was because the line from the tank to the house was froze.

Kyle

 

[Mister Twister]

I didn't have the problem when I was running off my well either which had a bladder tank on it. When we went to public water they put in a pressure reducing valve and along with that comes a check valve then my pressure increased whenever the hot water tank expanded the water on heating it.

 

[oneoldbanjo]

Geez: The event is caused by the sidearm heating the water in the tank to higher than normal temperatures - and the water expands more than normal. It is recommended that water heater controls be set for a minimum temperature of 130 degrees to control bacterial growth, and my water heater is set at 140 in the non-OWB season. The sidearm has the potential to raise the water heater temperature up to 160, 170, 180?....it all depends on how hot your OWB is and how much domestic hot water you are using.

mimilkman1: The potential for an expansion problem is increased when you have a household that uses lots of hot water. If the family runs the water heater out of hot water - the water heater has ingested a significant amount of 50 degree water from the well, cistern or public water supply. This water will soon be heated up to 160 degrees or so and will expand significantly. If you don't run your water heater out of water and the water inside stays nearly hot - the expansion will not be a problem. It will also not be a problem if you have a well or cistern pump with a storage tank that has an air space to provide water pressure when the pump is not running - as the expanding water can just go back into the tank. It will also not be a problem if you have public water without any pressure regulator in the system - as the expanding water can just to back out into the service line. Expansion is a problem for homes with pressure reduction valves because they act like check valves and will not allow any flow backwards - and expanding water then builds pressure in the house lines and water heater. Sometimes people will find that the valves on their toilets open when the pressure builds too high, and these will start flowing before the T&P valve releases.

 

[mimilkman1]

Geez: The event is caused by the sidearm heating the water in the tank to higher than normal temperatures - and the water expands more than normal. It is recommended that water heater controls be set for a minimum temperature of 130 degrees to control bacterial growth, and my water heater is set at 140 in the non-OWB season. The sidearm has the potential to raise the water heater temperature up to 160, 170, 180?....it all depends on how hot your OWB is and how much domestic hot water you are using.

mimilkman1: The potential for an expansion problem is increased when you have a household that uses lots of hot water. If the family runs the water heater out of hot water - the water heater has ingested a significant amount of 50 degree water from the well, cistern or public water supply. This water will soon be heated up to 160 degrees or so and will expand significantly. If you don't run your water heater out of water and the water inside stays nearly hot - the expansion will not be a problem. It will also not be a problem if you have a well or cistern pump with a storage tank that has an air space to provide water pressure when the pump is not running - as the expanding water can just go back into the tank. It will also not be a problem if you have public water without any pressure regulator in the system - as the expanding water can just to back out into the service line. Expansion is a problem for homes with pressure reduction valves because they act like check valves and will not allow any flow backwards - and expanding water then builds pressure in the house lines and water heater. Sometimes people will find that the valves on their toilets open when the pressure builds too high, and these will start flowing before the T&P valve releases.

Thanks for that, very informative.

Kyle

 

[Geez]

Geez: The event is caused by the sidearm heating the water in the tank to higher than normal temperatures - and the water expands more than normal. It is recommended that water heater controls be set for a minimum temperature of 130 degrees to control bacterial growth, and my water heater is set at 140 in the non-OWB season. The sidearm has the potential to raise the water heater temperature up to 160, 170, 180?....it all depends on how hot your OWB is and how much domestic hot water you are using.

mimilkman1: The potential for an expansion problem is increased when you have a household that uses lots of hot water. If the family runs the water heater out of hot water - the water heater has ingested a significant amount of 50 degree water from the well, cistern or public water supply. This water will soon be heated up to 160 degrees or so and will expand significantly. If you don't run your water heater out of water and the water inside stays nearly hot - the expansion will not be a problem. It will also not be a problem if you have a well or cistern pump with a storage tank that has an air space to provide water pressure when the pump is not running - as the expanding water can just go back into the tank. It will also not be a problem if you have public water without any pressure regulator in the system - as the expanding water can just to back out into the service line. Expansion is a problem for homes with pressure reduction valves because they act like check valves and will not allow any flow backwards - and expanding water then builds pressure in the house lines and water heater. Sometimes people will find that the valves on their toilets open when the pressure builds too high, and these will start flowing before the T&P valve releases.

Thanks Banjo, it makes sense now.