Slowing down blower on heat pump?

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qcroanoke

Sometimes I don't know if I'm the boxer or the bag
Location
Roanoke, VA.
Occupation
Sorta retired........
The ladies are happy, so far. It will also help with another headache.... Breakers tripping all of the time from their little space heaters under their desks! They have actually turned most of them off! "Ms. cold nature" left hers on, she runs hers year round! They don't understand why you can't plug in a bunch of 1500 watt heaters on the same 20 amp circuit!

I thought that was only here where I work.
And they never will understand why they can't plug unlimited heaters in and the breaker kicks.
But the first time they lose a bunch of work on their computers because of it, then you'll really hear them howl!!!!
 
You should not call the manufacturer. You should look around the system for the name of the installer or HVAC company. Just call them and tell them what you did. Wait for their perplexed look, the sound of coffee hitting the phone, or something. Anyway, discuss it with them. They may have a smarter way to do it... here is an example from experience:

A multi-speed smart thermostat. It can detect the load on the system and adjust the fan speed in a less-womanly way. :p You know, it will use logic... pure logic. Tell the boss lady that the guys who install it really know their stuff, and for $200 or less, they might be able to save the sisters some money and do it the Right Way. (c) In either case, the newer thermostat could adjust the speed of the air handler as required.

If you can't see a sticker from the installer, look in the yellow pages and guess. The big guys will have the logo/brands you see on the unit.
 

hockeyoligist2

Senior Member
A multi-speed smart thermostat. It can detect the load on the system and adjust the fan speed, the newer thermostat could adjust the speed of the air handler as required.
.

That would require extra relays to be added to the air handler, correct? The helpful HVAC guy told me he didn't have any way of making it work on different speeds. I will have to convince her to let me get a quote before I call anyone else.
 

stickboy1375

Senior Member
Location
Litchfield, CT
Im running a 2 stage Heat pump at my house, and what I did what swap out the blower motor with this unit, Emerson Rescue, My fan (G) runs 24/7 at 600 rpm lowest speed, on a stage 1 call for heat/cool it speeds up (x) amount of rpm, and on a stage 2 call it ramps up to even higher (x) amount of rpm, but anyway, the Emerson motor requires no relays, you can apply voltage to any lead, if two leads have voltage at the same time, the faster of the two speeds will run... it works awesome in my house!

You would still require a few relays, but they could all be controlled by low voltage wiring, so you would have W1 as a coil, W2 as another coil, AUX as the final coil. This setup
would change the speed of the fan as needed by the operation of the heating system...
 
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hurk27

Senior Member
I have only one word for you guys:

LIABILITY!

If you are an electrical contractor and in your normal duty's do not work on HVAC, then most likely your liability insurance will not cover you when things go south, you are playing with fire, and with liability there is no such thing as signing off, that is a farce, you have altered the original installation and the building owner can say you said it would work, the first thing a judge would ask is are you an HVAC tech?

I know it is nice to help people out of a jamb but I politely refuse to do work to which I'm not either qualified or insured to do, I can't count how many times I have been asked to hook up the gas to a dryer or install a dishwasher, nope I'm not insured to do plumbing, I know of at least one contractor who was held liable when a flex gas line let go and blew up a house, luckily no one was hurt, but it cost him dearly to build this person a new house and cover the loss of their valuables, some irreplaceable.
 

Dennis Alwon

Moderator
Staff member
Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
I do know a heating contractor who almost always uses the lower speed but I think he may have it set up to go to a higher speed in the summer. The gentle air blowing really helps with the wind chill factor. The unit will run longer between cycles but the temp. should stay very comfortable. BTW, this guys systems also incorporate much larger than normal duct system. He has a very sophisticated system and usually cost about 2x what a normal system cost.
 

kwired

Electron manager
Location
NE Nebraska
I do know a heating contractor who almost always uses the lower speed but I think he may have it set up to go to a higher speed in the summer. The gentle air blowing really helps with the wind chill factor. The unit will run longer between cycles but the temp. should stay very comfortable. BTW, this guys systems also incorporate much larger than normal duct system. He has a very sophisticated system and usually cost about 2x what a normal system cost.

There will be some change in effeciency but not much - it will not be a noticeably longer cycle. Heat pump is going to produce around the same amount of Btu of heat in same amount of time, temperature of discharge air will be higher if blower is running slower - so you have a higher temp for a smaller volume of air vs lower temp vs larger volume of air -both containing approximately same rise in Btu.
 

hockeyoligist2

Senior Member
I have only one word for you guys:

LIABILITY!

If you are an electrical contractor and in your normal duty's do not work on HVAC, then most likely your liability insurance will not cover you when things go south, you are playing with fire, and with liability there is no such thing as signing off, that is a farce, you have altered the original installation and the building owner can say you said it would work, the first thing a judge would ask is are you an HVAC tech?

I know it is nice to help people out of a jamb but I politely refuse to do work to which I'm not either qualified or insured to do, I can't count how many times I have been asked to hook up the gas to a dryer or install a dishwasher, nope I'm not insured to do plumbing, I know of at least one contractor who was held liable when a flex gas line let go and blew up a house, luckily no one was hurt, but it cost him dearly to build this person a new house and cover the loss of their valuables, some irreplaceable.

No liability here, I'm not an electrical contractor, I work for the company, signing off is all I need! My normal duties include checking out the HVAC Before they are called.
 

stickboy1375

Senior Member
Location
Litchfield, CT
No liability here, I'm not an electrical contractor, I work for the company, signing off is all I need! My normal duties include checking out the HVAC Before they are called.

Generally speaking, Most air handlers are setup to run at two speeds, one higher speed for AC, and a much slower speed for heat, since cold air is heavier to move you need higher blower speeds.
 
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