Furnace temperature rise

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I had a new 70,000 BTU Rheem furnace installed in my house. The airflow from the registers is rather noisy: You can hear the air rushing through the registers, not exactly whisper-quiet!
The temperature differential between return duct and heat register is 30 degrees (from 70F to 98F). Is this a normal differential or can the fan speed be reduced, resulting in a higher temperature at he registers?
Thanks
--
Walter
www.rationality.net
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So what did your installer say?
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This isn't alt.hvac. If you don't have something that will be of help crawl back to your snake pit where your buddies appreciate moronic replies. MLD
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I must have that guy killfiled, but he has a point. The OP may want to call the installer and explained what it is doing and express his concerns.
You never know: If HE attemps to change the fan speeds, he could possibly void the warranty.
Just a thought....
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When I had that same concern on my new unit I called the installer, I know just enough to understand there is a safe operating output temp and setting fan to low could be bad, and I dont know the safe limits. Also with wired taps I did not want to make a mistake that could ruin a board. So again I say talk to the installer first why risk ruining a unit under warranty or doing something stupid that you are not familar with. Installers have training and know their equipment and your house, you don`t.
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Actually there mr Dildo MLD Ransley gave perfect advice. The OP said it was JUST installed and with the info he gave (if its correct) I can tell you infact that it is NOT setup properly. They need to get out there and set it up right. The OP doesnt need to be messing with it and shouldnt be messing with it. He just paid for it and paid for it to be installed properly. You may now go crawl under the tunnel of your muddy rock. Bubba
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You dumbshit! How do you know the rest of the system is set up properly? What is the gas pressure? What about the orifices? What about the venting? What about the duct work?
Something is obviously wrong here, and the homeowner shouldn't have to be changing settings on his brand new furnace. He should call the installer and get it checked out and set up properly.
You sound like a real kunt.
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venting?
You have a point, many things to consider--but your response is still typical of the snake pit at alt.hvac. Just one question--between your hat size, your shoe size or your IQ---which one is bigger?
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At least he didnt give the hack reply to put in a restrictive air filter.... Since no one here knows the condition of the ductwork, and we can all assume that the installer just went and slapped in a furnace and didnt redo any duct, sure...lets half ass the air flow and since the OP prob has no clue how to check and adjust the gas valve, yay...lets create a possible senario that could...and thats COULD ruin a new installation.
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properly?
be
installer
hat
filter....
assume
senario
You're right--no fault in trying to give a proper response to someone's request for information or help. Every field, no matter what, requires expertise, experience and common sense. What you have over in alt.hvac is a bunch of buffoons who relish every opportunity to dump on anyone who enters looking for some info or help. It's so bad there, you're even dumping all over yourselves. Don't start bringing that trash mouthing here. HVAC is a specialty and there are things that you know that the average owner doesn't---however, it's not rocket science, lots of people can read a schematic, understand a wiring diagram and can up to a point, do their own troubleshooting. I also recognize that there are situations that are too dangerous to give advice, that doing the wrong thing can ruin an installation, if so, say so--have no fear, no one is going to take over your job, give a little respect if you want respect. MLD
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To someone that is looking for help, THIS is the right group to ask in. The other group was NEVER intended to be a self help group, and what alot of folks forget, is that in many states, its illegal for a homeowner to install, work on, or modify a unit...licences are a big deal. Now, with that ruling in I think it was the Netherlands, expect to start being held liable as we all have predicted for giving wrong advice that hurts someone...to someone with a licence, like myself, you have to pick and chose real careful.

the bad mouthing over there, is over a few users that are simply hacks. Period. Ive been in here for years, I dont post much in here..I go months and wont even look at the place...you can only tell someone to get a pro with training and INSURANCE so many times. No..its not rocket science..its fluid dynamics, and thermal dynamics, with a bit of electrical thrown in. And if you want the truth, there are times rocket science is prob more simple. Then again...with enough training, you too can do open heart surgery.

Respect is something I gain every day by being just like I am...I pull no punches, and dont sugar coat something just because you want it sugar coated..if teh damn things broke, its broke. Dont try to do like some EEs do and make it sound simple to replace a resister on a board...we dont do that, NOR would it be approved by any maker of a unit to start doing surgery on a board....as an example that is used in so often.
I will NOT sit here on every post and explain how many hours might go into something as simple as a manual T, or J, or D...I wont tell you how to do it either. I will tell you that the freebie online shit is that..shit..its not even close to what you encounter in the real world. You can run all the fill in the blank proggys you want, it does not do you a bit of good if you dont know EXACTLY what you are putting in. Diagnosis? No way anyone in the biz has time to cover each and every possible issue on every unit every time its asked. If you notice, most of the info in here, from the same bunch thats raising hell in the other group, is pretty much what anyone could ask for being that no one has that crystal ball. There are two in here that everyone loves cause they kiss ass...but they are two of the worst examples of the trade, to a real pro...hence, why they catch so much hell. Ive told people to fuck off in alt.hvac, and come over here and answer the question... Respect? I have that, and my paying customers show it, every time we get another call thats a referral...and yes Virginia, we get alot of them.
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I don't know, but my dick fits pretty good in your mouth.
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from
there are to many variables that are not stated in your post to even attempt a answer.
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That is a rather low temperature rise for a gas furnace. I would suggest dropping the blower speed one tap. I would normally expect to see between 40 and 60 degrees temperature rise with a gas furnace. See if the installer can do that for you.
BTW, the fan switch on the thermostat should be set to AUTO. If the switch is set to ON, you would be running at air conditioning speed. But the grilles should still not be that noisy.
Stretch
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Thank you, all.
The installer says that the fan speed in this dual-stage system is set by the factory and cannot be lowered. It's a Rheem 80% 2-stage Criterion Two+, Model RGPK 70.
The installation manual is of limited value.Wonder where I can find a maintenance manual. (The old tinkerer in me).
Maybe I can reduce the air speed by using a heavy duty air filter.
--
Walter
www.rationality.net
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although you might reduce the speed of the air flowing thru the heat exchanger (and consequently increase the temperature differential), you might at the same time adversely affect the amperage draw on the motor.
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I think you should call rheem , Im no pro but I thought a 2 stage had 2 fan speeds and different taps for different needs, but someone here will know.
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All furnaces come wired at a default speed and yes they can be changed. The default speed is based on an assumed external static pressure of .5" WC. If your system pressure is lower, then you could be moving an excess amount of air. The only way this could not be lowered is if the unit is shipped with the heating at the lowest fan speed. If this is the case, an after market accessory, such as a variable speed drive, could improve the unit's performance. For more info on drives e-mail me for info at cowlesandco at hotmail dot com
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wrote:

The model # will be helpful. By the way, I dont think you should have gone with the cheapest installer you could find. Bubba
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The installer says that the fan speed in this dual-stage system is set by

Sounds like BS to me. A pleated filter would lower air flow 10 to 20 percent. Try that. The fan speed IS set by the factory. It may already be set to the lowest speed tap, but probvably not. Most likely your installer is looking for an easy way out. Did he actually MEASURE the air flow when he installed the system? He should have.
Stretch
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