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Wiring a boiler. honeywell L8124A, C and aYr845a t stat calls for heat the circulators run but the boiler doesn'T FIRE what am i missing

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SOURCE: I have a coleman evcon

The most common wiring is: This sometimes varies as to installers preferance.
Red wire is your supply power to the T-stat. R terminal
Green wire is the blower fan. G terminal
Yellow wire is compressor contactor Y terminal
older units used a blue wire to Y
White wire is heat auxilary or black wire W terminal
Orange wire is reversing valve O terminal
Blue wire is the common C terminal
Black wire can be emergency heat E terminal
Best thing to do is replace wire for wire from t-stat to t-stat
or write down the colors to which terminal on the old t-stat and match to the new. make sure you SECURE POWER to the Air Handler, furnace and condenser before replacing any t-stat.
It is very easy to short the wires out if the power is left on and take out your A/H low voltage fuse or transformer.

Posted on May 18, 2008

  • 1 Answer

SOURCE: keston c40 honeywel 9400c programmer

do a s plan plus and buy a poly plumb roomstat combined programer with built in relays as you require the relays to stop back feed! simple!

Posted on Jul 23, 2008

  • 2 Answers

SOURCE: No hot water honeywell st6400c

HW valve was stuck in the open posiion and the micro-switch was not working so thats why boiler and pump were not starting. Bled system to below the level of the valve to be changed, and replaced valve with a drayton ( easy quick change of valve head if needed no screws )

Posted on Sep 17, 2008

  • 659 Answers

SOURCE: hot water boiler will not ignite

Check all your limit switches on this unit. One of them is either tripped or bad.

Posted on Apr 07, 2009

  • 234 Answers

SOURCE: what would the correct high and lo and diff

I would say high if you need cooling. If the tempature is cool enough for you then set it to low.If you are hot and need more cooling then high.

Posted on Apr 07, 2009

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