fan delay on make timer to help start up for ac generator

Received the ICM Controls ICM102B timer and it works. Took about 5 minutes to install, moved the thermostat fan low connector to the relay, made up a short jumper back the the control panel. Secured with a screw to the interior of the air filter plenum. Set at minimum, I get 2.5 seconds of delay, the adjustment is not linear, a small increase jumps the delay to 20 seconds. Maybe a bad unit. I turned off the converter and ran the batteries down to 11.35 volts and it still timed and latched reliably.

WDP

smkettner wrote:

Larryect wrote:
When I did mine I had some trouble finding a 12 volt relay. I think I found it at Allied electronics on-line. I had to add a resistor for the appropriate time-delay.

I had read about the mod on-line. It was a very good write up with instructions and links to a source for a cheaper relay. But at that time the cheaper relay was no-longer available.

For the life of me, I can't find that detailed write up again.

This should be it

If someone wants my agastat, send PM

Could be. Your post on the second page nails the process. Seems to me the one I saw before had pictures - but maybe not.

This worked great on my old Dometic with analog t_stat. Don't know if it would help the OP with controls in the housing, or with the new didgital stat's.

Larryect wrote:
When I did mine I had some trouble finding a 12 volt relay. I think I found it at Allied electronics on-line. I had to add a resistor for the appropriate time-delay.

I had read about the mod on-line. It was a very good write up with instructions and links to a source for a cheaper relay. But at that time the cheaper relay was no-longer available.

For the life of me, I can't find that detailed write up again.

This should be it

If someone wants my agastat, send PM

shooted wrote:

bob213 wrote:
Look at this thread. OP changed wiring method so correct way is from post #13 on.
Fan delay

Great minds think alike! I was thinking of this exact thread. Strange, I contributed to that thread and all of my posts are missing. This is the reason you will notice some gaps in the conversation.

Pic shows 7.5 volts on the thermostat, not likely with everything running off of 12. If it works for this poster, sounds like a mod to try.

WDP

When I did mine I had some trouble finding a 12 volt relay. I think I found it at Allied electronics on-line. I had to add a resistor for the appropriate time-delay.

I had read about the mod on-line. It was a very good write up with instructions and links to a source for a cheaper relay. But at that time the cheaper relay was no-longer available.

For the life of me, I can't find that detailed write up again.

I think I would mate that timer with a relay that could easily handle the fan running amps.
1.5 amp rating seems a bit light.

And yes I had installed similar in the wall thermostat control circuit. Worked great. agastat was the delay unit and it was 12v based. 12v is hard to find as most units (non-RV) are controlled with 24vac.

C Schomer wrote:
The best thing for starting an AC compressor is to have the pressures equalized and that gets done faster by running the fan. If you want to get creative with delays, stop the fan for a couple of seconds when the compressor wire get a call from the tstat. That will help the pressures equalize and kill the fan power for a moment at compressor start up. Craig

To increase component life expectancy and to lower amps drawn by the compressor on startup, a low pressure differential is important. In this application equalization takes place during the compressor off time when the high pressure side bleeds thru the cap tube to the low pressure side. Fan operation, or the lack there of, will have little to no effect on equalization. Ensuring the system(compressor) has enough time(off) is the important factor concerning equalization.

bob213 wrote:
Look at this thread. OP changed wiring method so correct way is from post #13 on.
Fan delay

Great minds think alike! I was thinking of this exact thread. Strange, I contributed to that thread and all of my posts are missing. This is the reason you will notice some gaps in the conversation.

gbopp wrote:
Clicky

Reading the specifications, says 18 to 240 volts AC, an older catalog for the same switch states 18-240 volts AC/DC. Inquiry to ICM produced this response:
RE: Product Inquiry : ICM102 - Delay-on-Make Timer with .03-10 minute adjustable delay, universal 18-240 VAC
Pete:

One thing to note, the timer will not work on only 12VDC. It took 18VDC to latch. This makes sense because it is rated 18-240VAC and the old books state 18-240 VAC/DC.

Regards,

John Fannetti
ICM Controls
7313 William Barry Blvd
North Syracuse, NY 13212
315-362-9363

Now, my question, does anyone have one in service that works on 12 volts DC? (control voltage for air conditioner)
Thanks in advance.

WDP

The best thing for starting an AC compressor is to have the pressures equalized and that gets done faster by running the fan. If you want to get creative with delays, stop the fan for a couple of seconds when the compressor wire get a call from the tstat. That will help the pressures equalize and kill the fan power for a moment at compressor start up. Craig