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I have a Honewell CM921/927 wireless programmable room thermostat that is operating the combi boiler in AUTO mode even when the time setting is meant to be off (no output). The target temp is 20 deg and the room may be 21 deg for example, but still the flame icon appears on the lcd screen of the thermostat and the radiators are luke warm continuously. Once the time reaches a preset the boiler kicks in fully to give proper heating and the radiators become very hot. Any help to allow the thermostat to be left in AUTO without the continuing operation of the boiler out of any time settings would be appreciated. Regards Barry.

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If the room is at the set temperature even when the rad are warm the boiler is doing its job. It takes steel rads up to an hour to cool down so if they stay warm to the touch that is normal.It takes steel rads a long time to heat up when they get cold so its cheaper to let them not get real cold.I was told not to put a programmable thermostat on our boiler simply because it takes a lot of gas to bring your house up even two degrees. I run a non programmable and set our heat at 72 degrees and do not touch it all winter. There should be a water shut off on each rad so if you want your bedroom cooler just shut that shut off on that rad off.

Posted on Apr 10, 2017


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Posted on Jan 02, 2017

The HVAC Guy
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SOURCE: Goodman GSH130301AB heat pump with

the reversing valve wire needs to be on the o terminal.nothing will be on the b terminal on the thermostat

Posted on Oct 30, 2008

  • 67 Answers

SOURCE: hitachi

I would really call your installers back mate.

If you have anything to measure air temp with I will take you though some tests.

But at this point I would say that your air con does not have any gas and the installers should come back. If they will not come back you should contact Hitachi warranty

Hope this helps

Posted on Jan 11, 2009

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SOURCE: My outdoor heat will not

you need to go oside and look for a red reset button on the unit. you tripped the high ressure switch when you let your filter get that dirty. go check on this and when your done if it still is not working then ask me more.

Posted on Jan 25, 2009

Sea Breeze
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SOURCE: GE Heat/Cool model AJHS10DCBM1

OK I will be looking over the manual. Now that squeal sounds like the squirrel cage fan scraping the housing around it. Those units are so tight fit they can be twisted one way or tightened a little to much they scrape. I love them for there silence win they work right but hate them because my hand are too big to move things around inside them. Stay in touch I will be looking around while
multi-tasking today- I'll be here!

Posted on Feb 02, 2009

  • 478 Answers

SOURCE: Heat pump cycling on and off.

It sounds as if you you have a low charge of refrigerant, r22. When the unit comes on outside, the outdoor coils become the lowside, there is a low pressure switch that is tripping out contactor protecting the compressor.

Posted on Mar 11, 2009

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