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Hot water heater and water pump acting strange [message #248395] Thu, 24 April 2014 19:26 Go to next message
An87ttype is currently offline  An87ttype   United States
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Last year I put one of the hot water heater bypass valves with check valve on the water heater for winterizing. All went well. Now Spring is here and I turn the valve and fill up the heater. Great! That was easy. The strange thing is, now it's acting kind of like a pressure tank. The pump cycles real fast, and when you turn the water off it cycles slower and slower until it stops. If I switch the pump off, the water will run for a long time with just the pressure from the tank. If I switch it to bypass everything works normally.

So what's going on? Is there just air in the tank? Does not seem to be any air coming out of the faucet. I've never had this problem without the bypass. Doesn't seem to make a lot of sense to me.

Anybody have any thoughts?...Thanks all


1975 Eleganza II Hudson Valley NY
Re: Hot water heater and water pump acting strange [message #248396 is a reply to message #248395] Thu, 24 April 2014 19:41 Go to previous messageGo to next message
SeanKidd is currently offline  SeanKidd   United States
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Seems you answered your own question, you are pressurizing air in the system, could be at a dead end of a line or your tank, acts like a pressure vessel.

Sean and Stephanie
73 Ex-CanyonLands 26' #317 "Oliver"
Hubler 1-Ton, Quad-Bags, Rear Disc, Reaction Arms, P.Huber TBs, 3.70:1 LSD Honda 6500 inverter gen.
Colonial Travelers
Re: Hot water heater and water pump acting strange [message #248398 is a reply to message #248396] Thu, 24 April 2014 19:57 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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It sure sound like the bypass is not installed correctly Is it the type with two valves or one valve and a check valve or just one valve.

An easy way to get most of the air out is to open the safety pressure valve, but that will not fix your real problem. It sounds like the water exit at the top of the tank is not moving any water or air out of the tank.



Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Hot water heater and water pump acting strange [message #248415 is a reply to message #248395] Thu, 24 April 2014 22:41 Go to previous messageGo to next message
Bob de Kruyff   United States
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An87ttype wrote on Thu, 24 April 2014 18:26

Last year I put one of the hot water heater bypass valves with check valve on the water heater for winterizing. All went well. Now Spring is here and I turn the valve and fill up the heater. Great! That was easy. The strange thing is, now it's acting kind of like a pressure tank. The pump cycles real fast, and when you turn the water off it cycles slower and slower until it stops. If I switch the pump off, the water will run for a long time with just the pressure from the tank. If I switch it to bypass everything works normally.

So what's going on? Is there just air in the tank? Does not seem to be any air coming out of the faucet. I've never had this problem without the bypass. Doesn't seem to make a lot of sense to me.

Anybody have any thoughts?...Thanks all

Air in the system. It will work its way out.


Bob de Kruyff
78 Eleganza
Chandler, AZ
Re: Hot water heater and water pump acting strange [message #248417 is a reply to message #248395] Thu, 24 April 2014 23:13 Go to previous messageGo to next message
Bullitthead is currently offline  Bullitthead   United States
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Can you post a pic of your bypass installation? Air in the hot water heater is a bad thing...it should bleed right outta there as soon as you open the hot spigots in the galley and bath.

Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Re: Hot water heater and water pump acting strange [message #248436 is a reply to message #248395] Fri, 25 April 2014 07:28 Go to previous message
Matt Colie is currently offline  Matt Colie   United States
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An87ttype wrote on Thu, 24 April 2014 20:26

Last year I put one of the hot water heater bypass valves with check valve on the water heater for winterizing. All went well. Now Spring is here and I turn the valve and fill up the heater. Great! That was easy. The strange thing is, now it's acting kind of like a pressure tank. The pump cycles real fast, and when you turn the water off it cycles slower and slower until it stops. If I switch the pump off, the water will run for a long time with just the pressure from the tank. If I switch it to bypass everything works normally.

So what's going on? Is there just air in the tank? Does not seem to be any air coming out of the faucet. I've never had this problem without the bypass. Doesn't seem to make a lot of sense to me.

Anybody have any thoughts?...Thanks all

Daryn,

Important question to the diagnosis:
Have you gotten a reasonable amount of hot water out of the tank?

It sounds to me like your by-pass is not opening correctly and only opening the cold feed to the tank and the bypass. The hot water has to get drawn out of the top of the tank. What you are seeing would lead me to suspect that you by-pass is either a defective part or installed incorrectly.

This would trap air in the top of the tank, and water would only enter or exit by the bottom (cold) fitting.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
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