I have a evcon dgat070 and last year it was upgraded or downgrade I think because of heat exchanger issue's.
But I am a little ticked that they put a smaller orifice in and cut back my btu's to 64000 now the thing runs more.
When the tech wired in the aux limit switch,why would he wire it into the upper limit for the fan and not the lower for the gas valve??
The schematics on the furnace shows it being in series with the lower limit switch so my last question is
If something goes wrong to open this aux limit switch they way he has it wired won't it just make the fan run all the time.instead of shutting down the gas valve as intended?
In-case anyone else wants to know I live in NW Ohio.
Simidrm
Furnace changes due to recall issues
The upper limit switch is normally closed switch to I think 180f and when bypassed it just turns the fan on.
when I bypass or unhook the lower limit it shuts down the gas valve,so according to the schmetics it shows wired to the lower limit,which makes sense it would shut down the gv if the temp gets to hot,not just keep the fan running
any way I am replacing both upper,lower limit switches as It's not worth risking a problem later as it is now the lower limit switch went out causing the gv to shutdown at the same temp as the fan comes on and then a get the 4 flash code and I jumped the lower switch and everything has worked correctly,so to be safe I rewired the aux switch from the upper limit to cover the bypassed lower limit as I have ordered both from here a couple days ago.
Normally I wouldn't do this but it was really cold here in the single digits last week so I assume it's safe with aux limit covering for the lower.
simidrm
when I bypass or unhook the lower limit it shuts down the gas valve,so according to the schmetics it shows wired to the lower limit,which makes sense it would shut down the gv if the temp gets to hot,not just keep the fan running
any way I am replacing both upper,lower limit switches as It's not worth risking a problem later as it is now the lower limit switch went out causing the gv to shutdown at the same temp as the fan comes on and then a get the 4 flash code and I jumped the lower switch and everything has worked correctly,so to be safe I rewired the aux switch from the upper limit to cover the bypassed lower limit as I have ordered both from here a couple days ago.
Normally I wouldn't do this but it was really cold here in the single digits last week so I assume it's safe with aux limit covering for the lower.
simidrm
Oh forgot a question,since the upgrade they put in a smaller orifice,would it be any problem to put the origianl size in and go back up to the 70,000 or would you recommend not doing this,my reason for thinking this is since they lowered the btu's to 64,000 it seems to run longer and cycle more then when it was hotter or so it seems to me anyway.
Thanks for the advice and availability of parts.
simidrm
Thanks for the advice and availability of parts.
simidrm
Leave the orifice as is, it is no longer designed for the larger btu's.
The Upper Limit Switch is as I stated above. It is a safety that in the event of blower failure while furnace is firing, at 180* it will shut the Gas Valve off.
It is NOT to keep fan running.
Thanks,
Robert
The Upper Limit Switch is as I stated above. It is a safety that in the event of blower failure while furnace is firing, at 180* it will shut the Gas Valve off.
It is NOT to keep fan running.
Thanks,
Robert
-
- Similar Topics
- Replies
- Views
- Last post
-
- 5 Replies
- 18576 Views
-
Last post by Greg
Sat Apr 06, 2019 4:51 pm
-
-
Intertherm/Nordyne feh-015ha furnace issues blower not working, unit will only turn off at breaker box
by onmypath78 » Sat Mar 16, 2019 12:11 pm » in Nordyne Service & Repair - 0 Replies
- 167387 Views
-
Last post by onmypath78
Sat Mar 16, 2019 12:11 pm
-
-
- 0 Replies
- 50110 Views
-
Last post by Kourgath
Fri Mar 23, 2018 3:41 pm
-
- 0 Replies
- 65432 Views
-
Last post by Chevy357
Wed Nov 13, 2019 7:47 pm
-
- 0 Replies
- 51416 Views
-
Last post by Elkaholic800
Mon Dec 16, 2019 12:39 pm