-
Low volume hot water
My volume of hot water has suddenly reduced. My cold water flow is excellent. Hot water very little volume. No new work done on plumbing. Pump and city water same result. The pump pressure is 60 pounds. City water also limited to samr PSI.
I have manifold for hot and cold flow. Manifold appears to be normal, have not taken apart yet. The volume is independent if amy using aqua hot to heat water, either on electrical or diesel. Same flow if not heating the water.
Any thoughts?
-
20 Replies
-
If its Aqua hot It maybe the mixing valve
-
Normally, the hot water for the coach starts at the Aqua Hot and is distributed from there. So if the coil or mixing valve of the AH is the source of the restriction, all hot water facuets would be affected. If only some facuets are affected, the restriction is not in the AH.
Using the electric or diesel function does not affect hot water pressure or flow.
The coil does not normally suddenly stop up. But a bit of debris could restrict the mixing valve.
A converter can add more hot water heating devices which complictes finding the restriction. I would check the water flow into the AH. If good I would check the flow out of the AH. If good, it is in the coach somewhere and a Prevost repair guy would be the go to person for that.
If the water flow out of the AH is not good, check the flow out of the fresh water coil before the mixing valve. If good it is the mixing valve that is not to hard to replace. If poor, then clearing sediment from the coil is a challenge using forward and backward flushing with water pressure and perhaps air pressure.
A sudden restriction would probably not be a build up needing vinagar to hopefully desolve before desolving the copper pipe. If coil is restricted and can not be cleared, it is not repairable per Aqua Hot. But the heater can usually be remanufactured at Aqua Hot. If you do need a reman of your heater, I woud be happy to do what I can for you to get this done. A message to me would let you know what the possibilities are.
Good luck in sorting this out.
-
Rudy Thanks
you will be a great resource for us.
GregM
-
Rudy already has been a fantastic resource for us and we can highly recommend him. He was a great help to folks at Oysterfest.
-
Thanks everyone. Will try and figure this out when when I am not dry camping since testing is going to use some water. We are dry camping (ecpet for electricity) which is good since still have generator problem that I think is voltage regulator and do not want to waste water testing things right now. Next stop we are hooked up full xervice, so that is where will address.
-
Reviving this thread since have had time to do testing and tried some repairs. I thought the problem was the mixing valve. On this older unit this is brass valve soldered in. I replaced all of the guts including thermostat and control valve since before change had great flow when set at the coldest setting but poor flow when set anywhere else on valve of the mixing valve. This did not change anything. Spoke to Rudy (our advertiser) at Aquahot and Hydronic RV services (great guy and very helpful) who feels with the trouble shooting I have done the problem is either sediment or other buildup in the coil. He instucted me in possible method of clearing. I will try that next week when have some more time. At present we have warm, not hot water in a low volume but enough to do what we need.
The bad news is if not able to clear coil may need a new aquahot (ouch).
-
Morning,
Where are you located please Sir? Depending on the “Where:, I know of some very good folks that can help you.
If you wish to replace the heater, you have two choices. One is to reman your heater. Your heater would be removed, sent to Aqua Hot in Frederick, Co, remaned and shipped back to you. From start to finish is about a month.
Second is a new heater. Takes two days to do the work and cost about $2k more than the reman. New heaters run very well and have a electronic control board. Yours has relays to control the pumps and fans so a relay adapter board would need to be used to adapt your thermostats, fans and pumps to the new heater.
I would certainly like to help you if you could come to the east side of Houston in Baytown, Tx. I have 50 amp hook up under a large covered area for either choice. But I would be happy to share hints if you wish to do the work yourself. Sure would like to sell you the reman or new heater. I know how to get the adapter board if you choose a new heater.
It is your bus so please know I would want you to use folks you feel are best for you. My phone is 7 one 3 – 8 one 8 – 3234 if you would like more info.
All the best as you make you decision.
-
I had a similar problem with my 06 Liberty It turned out to be a defective backflow preventer on the hot water line coming from the HW heater.
Check your system for a check valve in the line. They fail sometimes.
Good Luck
-
Roger,
Very good catch. If the heater is detached from fresh water supply and one gets good flow, that becomes a top suspect.
Where in the piping is your check valve located? Check valves can be deleted if one wishes. Some converters install them and some do not. Not an Aqua Hot spec.
-
On my Libertys the check valve has been on the cold water side supplying the HW tank.
If it is the issue you can leave it off. I believe it’s purpose is to prevent hot water from backflowing into the cold side if the cold side pressure drops. On a Liberty it should have a pin hole in it so the back flow is severely restricted, but the expansion due to water heating is handled by the accumulator / expansion tank. Failure to provide that relief hole might cause the HW tank pressure / temperature relief valve to open, especially when heating the tank with engine coolant.
-
I picture of one of these would be helpful. My aquahot is in a very hard to reach place. I have to remove a panel from rear of first bay, and then it sits between the partial depth right and left second bay. A real B—- to get at. A picture of one of the valves would be very helpful.
-
Hello Rudy,
This is Kim Sloan, we spoke on Friday. Right now I am in Gardiner, MT.
-
Kim,
Oops, did not realize it was you I spoke with — a senior moment before my time.
The check valves I have seen are brass in color and about 3/4 inch in diameter, 1 and a half inches long. A brass cylinder with flats on each end that have female threads usually. Sorry, I do not have a picture.
They can be placed any where along the fresh water line. I have even seen them in the cold water line coming into the heater. Good luck from me too. I hope you do not need a heater.
-
Problem solved, thanks to everyone who offered support and help. On Friday with the help of Don from RV service in Ennis, MT we were able to clear the aquahot coil.
We first tried to free the lines with air pressure. We could not get any volume of air through the hot water coils. We then set up a water pump to put 55 pounds of pressure into the line with pure vinegar through. At first got almost no flow. Then got slight flow, not enough to have pump run continously. The color of the vinegar in the outflow slowly became slightly green on color (this was promising). Then after doing this for around 4 hours suddenly alot of material (scale) came out of the outflow, flow became great, and pump would run continously without any back pressure. We allowed this to work for around 2 more hours. Flushed the system with gallons of water (actually attached city water to the inflow area.
Now everything back to normal, great hot water with great flow. I have left the two T line into the system, one on inflow cold water, and one on outflw hot water in place, so if happens again can flush again.
-
The green sounds like the copper coil had a lot of corrosion. Copper is pretty reactive so that is not a surprise.
Log in to reply.