NEED HELP! LOST MY HOT WATER

[jimdeq]

I hooked up a sidearm heat exchanger to my 50 gallon propane water heater. I came out of the bottom and placed a tee. Off the side of the tee a 2inch nipple to a elbow then a union. After the union my gravity recirc line tees in. After the recirc tee is a ball valve and then to the sidearm exchanger. In the end of the tee I screwed in a threaded well for the aquastat. On the top I pulled out the pressure relief and placed a stainless tee. Pressure relief was then placed back into the end of the tee and copper was piped out of the top of the tee and up about 12inches and then horizontal back to the top of the sidearm. My plumber installed a Watts mixing valve. On the gauge after the mixing valve it says the water is 130 degrees. Prior to doing all this when I turned on a faucet we had almost instant hot water. Now when we open the faucet it takes up to 4 min to get warm water. After a couple minutes of warm water it starts to get hotter. Heres the funny thing, after all this and 10 minutes of running hot water and shutting it off for 5 minutes and I turn it back on, the hot water is gone again and it takes minutes to get it back. I apologize for the confusing post. What am I doing wrong? Please help everyone in this house is mad?

 

[benjamin]

I'll take a shot in the dark and guess that the gravity recirc line doesn't have a check valve so it's letting cooler water flow back to the hot water faucet instead of straight 130 water like you want.

Is the recirc line new with this problem?

 

[leaddog]

I'm thinking the mixing valve is hooked up wrong or is not working properly. when you are trying to get hot water feel the pipe coming out from the tank and see if it is hot. you should be able to trace where you have hot water and where it stops and find the problem.
leaddog

 

[Medman]

You could be pulling water through the sidearm, from the bottom of the tank through your mixing valve and out to the faucets. The cooler water in the bottom would flow first, then get hotter as cold water and hot water in the tank mix. After you shut off the faucet, the tank stratifies again, with cooler water on the bottom. Turning the faucet on at this point gets the cooler water in the bottom of the tank again.
If I recall, I had to put a swing check valve in my setup someplace to prevent this from happening.

 

[jimdeq]

Thanks fellas, Benjamin, there is a check valve on the recirc that was always there uand last nite it started making a loud constant pounding kinda like water hammer. I closed the ball valve half way that is just prior to the check valve and the pounding stopped??????

Leaddog, I think the mixing valve is hooked up correct. The pipe after the valve is warm and the gauge reads 80 degrees static. When hot water is drawn upstairs the gauge goes up to 120 degrees,but it takes forever to get even warm water and longer for hot.?????

 

[leaddog]

Leaddog, I think the mixing valve is hooked up correct. The pipe after the valve is warm and the gauge reads 80 degrees static. When hot water is drawn upstairs the gauge goes up to 120 degrees,but it takes forever to get even warm water and longer for hot.?????

If the pipe just above the mixing valve is going up to 120* then the mixing valve seems to be working. You are getting hot water then flowing. This makes me wonder that before you had a ghost flow and had hot water going up the system and now you have stoped that and because you have long pipes you are just moving the water in the system before you are getting hot at the fauset. If that is the case you will see a BIG drop in your energy bill cause you were continueing to try and keep your plumbing lines hot. You may have large water lines like 3/4 or 1in and it takes a while for hot water to get to the fauset.
Just a thought. If this is the case you might want to think about putting in 1/2 in pex as that would get the water to the fauset faster and also have less water in the lines to cool off each time saving alot of hot water over time.
leaddog

 

[jimdeq]

Leaddog, the thing is I never had this problem prior to installing the sidearm , but I also thought I burned alot of propane. My house is very long with bathrooms on each end. It is possible to lose alot of heat with 80 feet of 1/2" line uninsulated?
Medman, sorry for the delayed response,but what would make me be pulling water from the bottom of the tank. I dont have the supply from the wood boiler piped yet os im just flowing through the DHW. I have a check valve where my gravity recirc tees off. Right know I have the flow throgh the sidearm shut off and the gravity recirc shut off. I have hot water after three to four minutes. Keep thinking please im confused?

 

[tom in maine]

A drawing would be very helpful.
I'll second on short-circuiting through the sidearm, but would really like to see a detailed photo or a drawing.

 

[benjamin]

What happens if you turn off the ball valve next to the check valve on the recirc line? It's possible that draining and working on the system moved some junk into the check valve. I'd like to know what the water hammer is about, no ideas here though.

If you're saying that you have 80 feet of uninsulated copper line leading to one bathroom then that would lose a lot of heat if it was recirculating, but it probably shouldn't be an issue in this problem, unless your system was recirculating before so you had hot water in a second or two and now it's taking ten seconds because the recirc isn't working? Half inch line will get hot water to the faucet much faster than bigger line because there is less cold water to run first.

 

[leaddog]

Leaddog, the thing is I never had this problem prior to installing the sidearm , but I also thought I burned alot of propane. My house is very long with bathrooms on each end. It is possible to lose alot of heat with 80 feet of 1/2" line uninsulated?
Medman, sorry for the delayed response,but what would make me be pulling water from the bottom of the tank. I dont have the supply from the wood boiler piped yet os im just flowing through the DHW. I have a check valve where my gravity recirc tees off. Right know I have the flow throgh the sidearm shut off and the gravity recirc shut off. I have hot water after three to four minutes. Keep thinking please im confused?

Did you ever hook up 100ft of hose and turn the water on and wait for the water to come out. It takes a while. That said 3 or 4 min is along time.
It also depends where the pipe is that is uninsulated because if it is quite cool it has to heat 80ft of pipe up also and that will take the heat out. Thats one of the advantages of pex it don't have the mass of pipe. insulating WILL save you money no matter what the outcome of your problem.
leaddog

 

[jimdeq]

I will clarify a couple things. The water heater is central in the basement with 40 feet each way to bathrooms, not 80 feet one way. The water hammer I exprienced was constant until I shut the ball valve prior to the check valve. I dont understand what Medman and Benjamin mean when they say " short circuit through sidearm". As for right now the only thing different then it always was is that the recirc line is 7 inches further away from the bottom port with one elbow inbetween. The sidearm is about a foot longer than the two ports on the water heater so the plumbing on the bottom is level , but the top sidearm plumbing comes down a foot into top port of water heater to a tee with PRV. I took pictures,but I am trying to learn how to post them.

 

[benjamin]

I thought the cool water was going through the recirc line and out the faucet along with the real hot water. I think medman thought the water was coming out of the bottom of the tank through the sidearm and into the "hot" line.

From the description, I'm now more confused, does the top tee that the relief valve is in have a way for the air to escape? could that be causing the water hammer?

eagerly awaiting pics to see how wrong I've been.

 

[ABM2958]

When you say that the top piping from the sidearm drops down into the top port of the water heater with a tee I'm thinking that you have stopped the thermosiphon. I've seen this before and would drop your bottom down so that you can get the top of the sidearm flowing naturally into the tank, preferably through the temperature / pressure relief port with a tee. It will naturally draw the cold water in through a loop but won't push hot water down without a pump because it wants to rise with the convection action.

 

[jimdeq]

Here are some pics.