circulators come on in low limit when 2 minute timer is active

Retro_Origin · Post by **Retro_Origin** » Fri. Dec. 24, 2021 1:02 pm

Thanks guys, I picked up the conversation here but to answer your q's:

lzaharis wrote: ↑
Fri. Dec. 24, 2021 9:30 am

When was the last time you vacuumed out the air passage under the fire grates?? When was the last time you cleaned the ash build up out from behind the removable baffle at the flue breech-I found out about this the hard way as it was never described in "their" owners manual.

I did both twice this year already, once end of winter and then beginning of fall. The ash build up clean was mostly just as high as I could reach with the brush.

Pacowy wrote: ↑
Fri. Dec. 24, 2021 9:53 am

If it's one of the newer models, it may be slow to respond at least in part due to the [insert expletive] secondary blower. In making the ash look better, that blower consumes the coal on the grate when there is not even a call for heat. This forces cooling air into the combustion chamber and adds to the time required for the stoker to achieve a good burn.

I've found that anything more than 1/4 open and that secondary just burns out my fire.

McGiever · Post by **McGiever** » Sat. Dec. 25, 2021 12:57 am

A aquastat control for a "dump zone" could possibly also serve as a HH/L (high/high limit) which can be your 160* cut off...

lzaharis · Post by **lzaharis** » Sat. Dec. 25, 2021 10:31 am

Hello and good morning, Retro Origin,

Based solely on what information you have provided us I candidly think you can remove the secondary blower successfully and have fewer problems with your K-6 by increasing the number of hold fire cycles exactly as I have done with my Kaa-4.
When I purchased my kaa-4 It did not have the secondary combustion fan, but after 2 years of trial and error and replacement of the digital controls twice with a set of Honeywell L8124L triple aquastat and B+G mechanical RB1-122 LWCO controls at great expense to me with no help from keystoker or the retailer I purchased the boiler from.
The boiler works and works well but the home is poorly insulated and can not keep up at times. I can sleep nights knowing it works just as they did when the machines were initially designed in 1947 with the control of the single aquastats.

Several of the forum members have removed thier secondary combustion fans with better operating results.

My hold fire timer pin settings for my 30-minute hold fire timer are set for ten minutes of idle time burning as follows:

3 minutes at zero time

2 minutes at 7 minutes

3 minutes at 15 minutes

2 minutes at 23 minutes

Having the hold fire time split over 4 periods guarantees that I will not lose my fire unless we have a power outage.

I candidly feel I am not wasting rice coal with the extra time on the hold fire timer as my chimney is only 19 feet tall with the chimney extension.

McGiever · Post by **McGiever** » Sat. Dec. 25, 2021 6:00 pm

lzaharis wrote: ↑
Sat. Dec. 25, 2021 10:31 am
Hello and good morning, Retro Origin,

Based solely on what information you have provided us I candidly think you can remove the secondary blower successfully and have fewer problems with your K-6 by increasing the number of hold fire cycles exactly as I have done with my Kaa-4.
When I purchased my kaa-4 It did not have the secondary combustion fan, but after 2 years of trial and error and replacement of the digital controls twice with a set of Honeywell L8124L triple aquastat and B+G mechanical RB1-122 LWCO controls at great expense to me with no help from keystoker or the retailer I purchased the boiler from.
The boiler works and works well but the home is poorly insulated and can not keep up at times. I can sleep nights knowing it works just as they did when the machines were initially designed in 1947 with the control of the single aquastats.

Several of the forum members have removed thier secondary combustion fans with better operating results.

My hold fire timer pin settings for my 30-minute hold fire timer are set for ten minutes of idle time burning as follows:

3 minutes at zero time

2 minutes at 7 minutes

3 minutes at 15 minutes

2 minutes at 23 minutes

Having the hold fire time split over 4 periods guarantees that I will not lose my fire unless we have a power outage.

I candidly feel I am not wasting rice coal with the extra time on the hold fire timer as my chimney is only 19 feet tall with the chimney extension.

Being he has a K-6 with a totally different stoker design than yours I would wager a guess your pin settings will not be his salvation. Besides everything else his chimney has high probability of being nothing near matching yours either so all bets are off for those considerations.
Other that those discrepancies carry on!

Pacowy · Post by **Pacowy** » Sat. Dec. 25, 2021 8:04 pm

Even if the pin settings are different, the general proposition that you can efficiently run a KA-6 without a secondary blower is sound. By adjusting towards a thicker coal bed, I expect one would be able to reduce run time needs on timer cycles.

Mike

Retro_Origin · Post by **Retro_Origin** » Sat. Dec. 25, 2021 9:01 pm

Pacowy wrote: ↑
Sat. Dec. 25, 2021 8:04 pm
Even if the pin settings are different, the general proposition that you can efficiently run a KA-6 without a secondary blower is sound. By adjusting towards a thicker coal bed, I expect one would be able to reduce run time needs on timer cycles.

Mike

Thicker bed meaning quicker pickup and more 'buddy coal burning up his neighbors'? Are you saying I should aim for as thick of a bed as possible and think less about my air adjustment? I'm new at this, remember!

Notice I've actually disconnected the secondary as far as idle purposes go. It is being used in conjunction with the primary to supply more air since I'm still seeing what "appears" to be unburnt and every increase in air has provided a quicker and hotter fire.

Please continue this topic on the other thread if possible

Post by **Rob R.** » Sun. Jan. 02, 2022 11:21 am

cardinal wrote: ↑
Wed. Dec. 22, 2021 10:27 pm
EFM 520 STOKER SETTING 200 HIGH 160 LOW 10 diff
Stoker with 4 zones and two zones calling for heat,
stoker keep running below low limit (ok)
circulators shut off at 150 and come back on at 160(ok)
Digital timer runs 2minutes every ½ hour (ok)
Honeywell Aquastat L7224
TACO SR503 3 ZONE Switching Relay

Need Help
The Problem starts with stoker running on low limit and the circulators shut off, (at 150)
for some reason during the low limit, power is getting to the circulators only when the 2 minute timer comes on, and the circulators shut off when timer shuts off after the 2 minutes . When stoker is idle and timer comes on it does not affect the circulators and everything is normal .This problem is cooling down the boiler below the 150 and it only does this when 2 minute timer is active as the boiler heats up 150 rising to 160, after 160 circulators power back on and everything is OK
Could it be the TACO SR503 3 ZONE Switching Relay (ice cube relay look ok )
ZR wire on taco relay goes to ZR in Aquastat and to ZR on to 2 minute timer
Note : don't know what is wrong it ran good for 11 years Thanks

Did you get this figured out?

cardinal · Post by **cardinal** » Tue. Jan. 11, 2022 12:53 am

Changed thermostat for one zone now ok,It Kept shutting off (short cycle ) As for the other zone it might have had a stuck cube relay ,In the taco switching relay ,now that also is ok. Now for the timer. I put old Wil Burt timer back on and it also starts the circulator when boiler is in the low limit rising making heat. So I put the new electronic timer back on same results. Timer starts boiler and circulators in low limit . The ZR wire goes from timer to ZR in the aqua stat to ZR in the switching relay. ZR Some how sends power to ZC in switching relay as the low limit is rising up and the 2 minute timer comes on .When timer comes on it should send power via ZR to start boiler. Not to power circulator. ZR some how is sending power to ZC in the taco relay box on low limit only . When above low limit setting ,it’s OK the timer only starts boiler Thru the ZR. and does not turn on circulators thru ZC . Maybe it always did this. Never noticed it. Or the relay box has a gone bad. I guess I will just change switching relay box. Thanks

Post by **Rob R.** » Tue. Jan. 11, 2022 9:51 am

cardinal wrote: ↑
Tue. Jan. 11, 2022 12:53 am
I guess I will just change switching relay box.

If you are going to change the zone relays, get one that is large enough for all of your zones and wire it like this:

.PNG | 50.9KB | Screenshot 2022-01-11 095001.png

If you find that your boiler frequently runs up to the high limit setting, I would run the wire from the isolated end switch though a toggle switch and leave that "off" unless more heat is needed. More than likely the low limit of 160 degrees is plenty to heat your house and hot water 95% of the time.

cardinal · Post by **cardinal** » Fri. Jan. 14, 2022 7:55 pm

The zones are wired to a taco three zone switching relay. Zone 4 runs off of c1 c2 on aquastat .the one zone does heat boiler to high limit. Thanks for the tip to put toggle switch on isolated end switch wire going to TT on aquastat. Thank You. Rob. U always solve my boiler problems Thanks again