Soft start for air handler?

 
creek44
Member
Posts: 112
Joined: Tue. Aug. 23, 2011 12:20 pm
Location: Eastern Ohio
Stoker Coal Boiler: EFM 520
Coal Size/Type: Rice

Post by creek44 » Thu. Oct. 17, 2019 11:35 am

Happy heating season to all!
My air handler for the water to air heat exchanger has always started with a “bang” which is not only annoying but detrimental to the motor and drive. I had to replace the motor last heating season. The motor is 1/2 hp 115/230v capacitor start wired for 115v. It is a belt drive blower and is thermostatically controlled with a 24v relay. I installed a new blower shaft and bearings as well as a new belt when replacing the motor. I upgraded the pulleys to cast iron. Belt tension is proper. The blower runs smoothly after starting with the bang. This is nothing new since it has started in the same manner with previous motors. The motor life has only been 3-4 years which I feel is short due to the traumatic starts. I am looking at this soft starter but not sure if it is a good idea and what would be needed to thermostatically control it.
https://www.supplyhouse.com/Square-D-ATS01N112FT- ... ut-Voltage
Should I try to “fix it” or leave it alone?


 
User avatar
coalkirk
Member
Posts: 5185
Joined: Wed. May. 17, 2006 8:12 pm
Location: Forest Hill MD
Stoker Coal Boiler: 1981 EFM DF520 retired
Hand Fed Coal Stove: Jotul 507 on standby
Coal Size/Type: Lehigh anthracite/rice coal

Post by coalkirk » Thu. Oct. 17, 2019 12:49 pm

Start up is the hardest thing for electric motors. I'll tell you what I do and I know I'll be immediately criticized here for it but I run the fan motor 24/7 in the heating season. My air handler is a variable speed so when there is no call for heat it runs at a low CFM rate. When there is a call for heat it ramps up to a normal CFM rate. Yes it uses more electric. I don't care. I'm saving enough using coal. This method eliminates the start up from 0 and keeps the air in my home moving, mixing, filtering and adding humidity. It's a comfort thing and as this motor is now 20 years old it doesn't seem to have affected its service life. I'm told its a pricey motor.

 
creek44
Member
Posts: 112
Joined: Tue. Aug. 23, 2011 12:20 pm
Location: Eastern Ohio
Stoker Coal Boiler: EFM 520
Coal Size/Type: Rice

Post by creek44 » Thu. Oct. 17, 2019 1:45 pm

Good alternative. Thanks. Easy no cost change other than electric consumption which is unknown at this point. I could even allow the blower to cycle with heat calls when not at home if desired. I am going to try to put a cost on running that motor 24/7 before committing to it. Your suggestion would give me time while considering other alternatives. We have a pool with a 1.5hp pump motor that boosts the summer electric bill a significant amount which makes me cringe a bit. Not sure of that cost due to the a/c running also.

 
User avatar
Lightning
Site Moderator
Posts: 14659
Joined: Wed. Nov. 16, 2011 9:51 am
Location: Olean, NY
Stoker Coal Boiler: Modified AA 130
Coal Size/Type: Pea Size - Anthracite

Post by Lightning » Thu. Oct. 17, 2019 2:46 pm

Look for a wattage or amp draw on the motor. It is 120 volt right?

Volts × amps = watts

A Kilowatt (1000 watts) is usually $.12 to $.16 per hour.. could be more, could be less. Take your total dollar amount on your monthly electric bill and divide it by total kilowatts to get a good number for your kilowatt price. It could be variable, in that case do a few months to get an average.

 
creek44
Member
Posts: 112
Joined: Tue. Aug. 23, 2011 12:20 pm
Location: Eastern Ohio
Stoker Coal Boiler: EFM 520
Coal Size/Type: Rice

Post by creek44 » Thu. Oct. 17, 2019 4:37 pm

Approximately $1 per day according to my calculation. 2.6 amps @ 120v.

Attachments


 
creek44
Member
Posts: 112
Joined: Tue. Aug. 23, 2011 12:20 pm
Location: Eastern Ohio
Stoker Coal Boiler: EFM 520
Coal Size/Type: Rice

Post by creek44 » Thu. Oct. 17, 2019 5:36 pm

I think that I misread the label. Should be 5 amps @ 120v? That would be $2 per day. Ouch! The last time I checked my electric bill I think that I calculated $0.14 per kwH.

 
xackley
Member
Posts: 252
Joined: Sun. Oct. 07, 2007 10:57 am
Location: Finger Lakes, NY

Post by xackley » Thu. Oct. 17, 2019 6:20 pm

Isn't 5 amps for the fastest speed and 2.6 for the slowest?
When I had a belt drive blower I would keep the belt a little loose so there was a little slip at start up.

Kinda relate would a speed controller like this save on electricity if set to a slower speed.
KBWC-15K
https://www.kb-controls.co/product.sc?productId=1 ... egoryId=25


 
creek44
Member
Posts: 112
Joined: Tue. Aug. 23, 2011 12:20 pm
Location: Eastern Ohio
Stoker Coal Boiler: EFM 520
Coal Size/Type: Rice

Post by creek44 » Thu. Oct. 17, 2019 7:33 pm

5 amps when configured for 115v is the same rpm as 2.6 amps when configured for 230v which is 1725 rpm and similar power consumptions. Actually slightly more consumption @ 230v. I tried loosening the belt slightly and it still “bangs on”.

 
User avatar
wilder11354
Member
Posts: 1221
Joined: Sat. Jan. 29, 2011 10:48 pm
Location: Montrose, Pa.
Hand Fed Coal Boiler: Harman SF260 Boiler
Hand Fed Coal Stove: Hitzer 50-93
Coal Size/Type: nut or pea, anthracite
Other Heating: crown oil boiler, backup.if needed

Post by wilder11354 » Thu. Oct. 17, 2019 7:40 pm

is the motor mounted on rubber isolator bushings? or hard bolted to frame work?

 
User avatar
McGiever
Member
Posts: 10130
Joined: Sun. May. 02, 2010 11:26 pm
Location: Junction of PA-OH-WV
Stoker Coal Boiler: AXEMAN-ANDERSON 130 "1959"
Hand Fed Coal Boiler: BUCKET A DAY water heater
Hand Fed Coal Stove: Warm Morning 414A
Coal Size/Type: PEA,NUT,STOVE /ANTHRACITE
Other Heating: Ground Source Heat Pump and some Solar

Post by McGiever » Thu. Oct. 17, 2019 8:03 pm

What I have done for similar results is to get the VFD (soft start) that inputs 240vac single phase and outputs 240vac 3 phase then changed the motor to a 240/480 vac 9 lead 3 phase motor to run at 240vac 3 phase.

Works smooth as ever that way. Definitely runs at less watts than at 120vac and that motor doesn't get very hot either.
All it takes to cycle the fan is a switch with a dry contact, such as any t'stat or relay could.

 
creek44
Member
Posts: 112
Joined: Tue. Aug. 23, 2011 12:20 pm
Location: Eastern Ohio
Stoker Coal Boiler: EFM 520
Coal Size/Type: Rice

Post by creek44 » Thu. Oct. 17, 2019 8:19 pm

The motor has rubber bushings.
How costly is the single phase to 3 phase changeover? Interesting. Sounds like it might be expensive.

 
User avatar
McGiever
Member
Posts: 10130
Joined: Sun. May. 02, 2010 11:26 pm
Location: Junction of PA-OH-WV
Stoker Coal Boiler: AXEMAN-ANDERSON 130 "1959"
Hand Fed Coal Boiler: BUCKET A DAY water heater
Hand Fed Coal Stove: Warm Morning 414A
Coal Size/Type: PEA,NUT,STOVE /ANTHRACITE
Other Heating: Ground Source Heat Pump and some Solar

Post by McGiever » Thu. Oct. 17, 2019 8:46 pm

creek44 wrote:
Thu. Oct. 17, 2019 8:19 pm
How costly is the single phase to 3 phase changeover? Interesting. Sounds like it might be expensive.
Price of the VFD, plus the 3 ph motor...about $200.00 maybe? Should last beyond your lifetime, so one and done.
I get what I need off of ebay for best deals.

 
User avatar
coaledsweat
Site Moderator
Posts: 13763
Joined: Fri. Oct. 27, 2006 2:05 pm
Location: Guilford, Connecticut
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

Post by coaledsweat » Thu. Oct. 17, 2019 8:57 pm

creek44 wrote:
Thu. Oct. 17, 2019 8:19 pm
The motor has rubber bushings.
How costly is the single phase to 3 phase changeover? Interesting. Sounds like it might be expensive.
Not very many homes have 3 phase service. I have seen a total of one in my lifetime. The guy had a machine shop in his basement.

 
User avatar
McGiever
Member
Posts: 10130
Joined: Sun. May. 02, 2010 11:26 pm
Location: Junction of PA-OH-WV
Stoker Coal Boiler: AXEMAN-ANDERSON 130 "1959"
Hand Fed Coal Boiler: BUCKET A DAY water heater
Hand Fed Coal Stove: Warm Morning 414A
Coal Size/Type: PEA,NUT,STOVE /ANTHRACITE
Other Heating: Ground Source Heat Pump and some Solar

Post by McGiever » Thu. Oct. 17, 2019 9:01 pm

CS, this doesn't need any 3 phase service, go back and reread, it is all powered by single phase, and then runs 3 phase motor from the single phase input. Lots of small 3 phase machines now need no 3 phase service.

C44, Another thought...find a 1/2HP, 2 or 3 speed furnace blower motor with same frame mount and shaft diameter as existing and wire it to start on low speed and after 12 seconds or so a timer connects in the medium or high speed winding to operate at.

 
creek44
Member
Posts: 112
Joined: Tue. Aug. 23, 2011 12:20 pm
Location: Eastern Ohio
Stoker Coal Boiler: EFM 520
Coal Size/Type: Rice

Post by creek44 » Thu. Oct. 17, 2019 9:22 pm



Post Reply

Return to “Coal Bins, Chimneys, CO Detectors & Thermostats”