Question about Pentair Minimax NT Heater

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Should check valve be open when the heater is running?

Should the flap on the check valve outlet be open when heater is running?

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What check valve?
if there is a check valve plumbed into a plumbing system, when pump comes on, then yes, check valve will automatically open!
its a one way valve! The water will flow against the flapper, pushing it open!
you have no control over that! And... Water always goes thru the heater! Whether it is firing or not / on or off, does not matter, if pump is on, water is also flowing thru heater.

Posted on Apr 05, 2015


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3 Answers

Only warm air in def no heat elsewhere

check the mechanism that controls the heat flow .The flap may not be opening fully thereby ,impeding the full flow of heat into the cabin. .

Jan 03, 2014 | 1996 Audi A4

1 Answer

No Heat, fan works engine is at temp.

Check to see if both heater hoses are hot when the engine has heated up and the heater is running.

You have 2 possibilities. One is that water valve is not opening and the heater core is cold, the second possibility is that the heater core is hot and the ductwork under the dash is not switching the flaps to give heat.

If both heater hoses are hot it means the heater core is hot and the interior ductwork is not channeling heat. You would then need to replace a movement valve or motor to switch the flaps in the ductwork.

Sometimes with the high priced options, there are self-diagnostics in the control panel of the heater. You would need someone to initiate the sequence and let the self-diagnostics pinpoint the bad part. Otherwise you need to dive under the dash and troubleshoot.

Feb 12, 2012 | 1995 Buick Regal

2 Answers

I have a 93 delta 88. heat comes and goes. we have changed the thermostat, and checked fluids. the car does not run hot. but the heat will work one day and blow cold the next.

Check the vacuum diaphragm in the heater hose. It's a little metal valve with a hose going to it. When the heat is turned on the vacuum line opens the valve letting hot water pass through the heater core.

Mar 14, 2010 | 1988 Oldsmobile Delta 88

2 Answers

Heater is blowing luke warm air. does not get any hotter

Quite a few idea's come to mind.
1) Thermostat is stuck open, causing the engine to run cool.
2) The vacuum valve that opens and closes the air "flap" is stuck open, allowing cool air in all the time.
3) The vacuum valve that opens and closes the line that feeds the heater core isn't opening all the way.

Jan 30, 2010 | 2004 Chevrolet Impala

3 Answers

99 jeep cherokee problem w/ heat I replaced the blower motor, water pump,radiator, thermostat and flushed the coolent system. Still getting little heat. I'm thinking heater core or head gasket... Is there...

It sounds like the heater coil needs flushing out or replacing or the heater valve. Look on the engine firewall and make sure the heater valve is opening. If not open it manually and check the heat level. If that produced heat check the condition of the heater vale cable (or vaccum hose).

Jan 05, 2010 | 1999 Jeep Cherokee 4WD

1 Answer

Relief valve is leaking

The relief valve is a SAFETY Device.... what every you do, don't plug the outlet....
These valves are designed to leak for one of two reasons: Too high of a water pressure or too high of a water temperature...

Be very careful around this because if it decides to open up more, there's most likely going to be alot of hot steam that can scald very rapidly.

First of all, check to make sure the thermostat on the water heater is not set too high...dial it down about 25%. Then watch to see if it's still leaking.

You may want to check your water pressure...has there been any increase that was noticeable lately?.. If not, you may want to replace the TPR valve with a new one... readily available ...
to do so, turn off the gas to the heater, close the inlet valve and attach a drain hose to the outlet on the side of the water heater and run the other end outside. Drain off enough water to allow removal of your TPH, install the new one using teflon tape liberally on the threads. Tighten and then close the drain valve, and open the inlet valve, and once the tank is full, relight.

Good luck..

Nov 19, 2009 | Rheem 40 Gallon FVR NATGAS Low WATER...

1 Answer

2005 chevy truck a/c works cant get heat blows cold

This sounds like a valve problem, or a heater/ cool air door stuck.
Many GM vehicles, have under the hood, a valve, it is electronic or vacuum controlled. When you switch the lever to heat, this valve opens, thus letting hot water flow through to the heater core.
On some newer models, there is a door (flap so to speak) within the interior compartment. This flap opens and closes between heater core and interior, thus controlling hot air flow.
Have you check to insure there is sufficient coolant in the system?
Low coolant levels will also cause no heat, but will also show signs of engine running warmer, sometimes much warmer than it should.
The valve under hood was as used on my 1995 Astro van. the mechanism looked to work as you could see shaft move in and out, problem was the diaphram or flap in valve on end of shaft (inside valve and not visible) was detached.
The other method, interior door or flab within heater box assembly was a problem on my 1998 Ford Expedition.
Yours, being GM, I would check for this valve under hood. It will be somewhat obvious in most cases as it will have heater tubes running into it and from it into firewall.

Oct 12, 2009 | Chevrolet C2500 Cars & Trucks

1 Answer

1994 where might the heater control valve be?

Look under the hood and follow the heater hoses and the valve will be in line in one of the hoses. Usually in near the heater core. If you see it and the cable or vacuum line does move the lever the valve could still be bad. To check take valve out and manually move the control and make sure the flap opens and closes. The flap may not work even though the lever is moving. Good Luck.

Sep 26, 2009 | 1994 Jeep Grand Cherokee

1 Answer

2000 Linc ls v8 auto question james from ILL.

maybe you won't need to. On the fire wall you will see 2 hoses an inlet and an outlet.that go directly into the heater core. Sometimes the heater core is clogged. disconnect the hoses and use a water hose running at only a moderate flow. put it into one of the the inlet of the heater core and run water until you see clear coolant. Then do it on the outlet and run it until the coolant is clear. you are trying to remove any clogs the heater may have. if this does not work, check the heater control valve.move the temperature slider the one to control the temp inside the car. and see if you can hear anything move. Check to see what type it is it can be a vacuum controled vavle, or a cable hooked on to the valve or an electronic controled valve. if it is a vacuum controled valve, you can check to see if a vacuume hose is disconnected, if it is a cable type valve,check it by moving the temperature control inside the car open it and close it with your fingers if you can see it. But most likely it may be the heater core thats clogged.

Nov 30, 2008 | 2000 Lincoln LS

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