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MONDAY MORNING MESSENGER

Message Prepared For Members of the American Institute of Inspectors®

January 25, 1999

GOOOOOD MORNING A.I.I.™

It's a great day at Michael Leavitt & Co Home Inspections! The snow is falling and the snow skiing is fantastic and getting better every day. Last week was as busy as any week in the middle of July. My wife Shelly and I keep looking at one another wondering what is going on. Traditionally the work flow is steady, but not overwhelming. Amidst the heavy work load came the idea to modify the name of the MMM. Instead of the Monday Morning Marketer, we have broadened the title and it will now be called the Monday Morning Messenger. The acronym is still the same...... MMM.

INCREDIBLE TECHNOLOGY

Today's edition of the MMM was authored by several members of AII's™ online membership. Special thanks to Ken Ives, Scott Merritt, Jon Gudnason, Bill Ball, John Renebstorff, Jim Lucas, Sylvan Stenge, and Dan Back. Earlier this past week I was e-mailed the Heat Pump freeze-up photos shown below by Ken Ives in Sacramento, California. Instead of waiting for this edition of the MMM to present it to all of you, Ken needed a quicker answer. This need for information spawned the idea to send out a Monday Morning Messenger Newsflash. The responses were incredible, informative, and quite lengthy in quality content. I have reformatted each of them in this edition to compile all of the topical information together in one document. This will be a great resource to re-read a year or two from now when each of us encounters the same situation.

Ken Ives has over 4 years of inspecting experience, yet he was able to draw upon our combined hundreds of years of experience. All of today's MMM information came back within 72 hours of Ken encountering the condition. That is incredible! The membership's feedback to Ken's photos was my dream come true. This is what I envisioned a year and a half ago when we started down this cyberspace pathway. Flash back with me to our previous method of answering Inspector questions. Just a year ago Ken would have sent the picture to the newsletter editor. Within a month or two it would have arrived in our mailboxes published in the newsletter. If we responded promptly, the answers would have come out in the following newsletter. All-in-all Ken would have got his responses within about 4 months of originally encountering the situation. Because of our modern cyber technology and the AII™ Inspector Hotline, Ken's first feedback came back from Scott Merritt within about 12 hours of Ken snapping the digital photo...... Incredible!!!

I would be very interested on how you feel about the technology that currently links us together..... E-mail me with your thoughts.

MONDAY MORNING MESSENGER

NEWSFLASH

A.I.I.™ MEMBER'S HELP NEEDED

Ken Ives from Northern California sent me some photos and he needs your immediate input.

SCENARIO: Residential structure with a heat pump system. The thermostat was set to heating and there was no apparent back-up emergency heat strips installed (Ken says this is common in his area). The blower motor was circulating air through the ducted system.

EXTERIOR TEMPERATURE: 48 degrees

INTERIOR TEMPERATURE: 44 degrees

EXTERIOR UNIT:

HELP NEEDED: Ken has never encountered this before. Does anybody know what happened. Why did it freeze up. What is the failure??? I realize that we don't need to concentrate on the "WHYs" but it would be very beneficial when it comes time to explain the condition to a client or agent what is going on. Ken is experienced and he reported it as needing immediate attention by a licensed HVAC. He then shut the system off, took some pictures and left completely puzzled.

I would love to know who has ever encountered this, and a detailed explanation of how the system works verses what went wrong to cause the freeze-up would be very beneficial to us all.

AII™ Members please send your responses immediately to:

AII-L@PEACH.EASE.LSOFT.COM

Non-AII™ Members please send your response to:

PeaceofMind@TheHomeInspector.com

I would be interested in any and all feedback.... So would Ken.

HEAT PUMP FREEZE-UP RESPONSES

You will immediately notice that all of the responses are from Northern California. Don't feel left out if you are like me sitting at least 700 miles from where Ken encountered the frozen up Heat Pump. This is a regional topic. Heat Pumps are not used much here in Northern Utah, if at all. We run about 95% Forced Air Gas Heating systems. I still read all of the information with great interest because I know that one day I will run across one.

The AII™ Inspector Hotline responses were quite informative. Compiling them back to back in the MMM setting is that much more impressive. I had been reading them as individual e-mail messages over the last few days and hadn't realized how much information was shared.

Scott Merritt was the first to respond to Ken Ives' question. He provided excellent information, and even a quick chastisement....... Uh, I mean encouragement for all AII™ members residing near Sacramento to attend the local monthly Chapter Meetings.........

John Rebenstorff gave us a great handout at the Sacramento area Chapter meeting last week. I'll quote him:

"Heat pump efficiency is reduced during cold, humid conditions. When the condenser, (outside air coil), on a heat pump is acting as the evaporator during heating operations and the outside air temperature is low and humid (foggy conditions especially) frost will form on the outside air coil. When this occurs the coil must be defrosted. This is accomplished one of two ways:

(1) by a sensor sensing the air temperature drop across the coil.
(2) a timer is used to put the unit in defrost for a few minutes every hour.

The defrosting of the coil is achieved by allowing the heat pump to operate in the cooling position, this causes hot gas to enter the condenser. Normally when the defrost cycle is energized the outdoor fan (condenser fan) does not operate. When inspecting a heat pump during
winter operations be aware of this condition."

In short, it looks as if the defrost mode is not operating, having to do with a stuck reversing valve, perhaps.

Hope this helps. It will be interesting to hear other responses.

Now Ken, if you had been to the Chapter meeting you would have had the answer at the job site and come across as a genius! See you next month?

Scott Merritt - Grass Valley, CA

Bill Ball passed along this succinct answer........

YES, the unit's "defrost" cycle is not functioning. A condensing unit freezes up like this when it doesn't "reverse" and go into air conditioning mode occasionally to heat up the coils to defrost the unit.

KEN: It should have been shut-off and a technician recommended... BILL BALL - Las Vegas, NV

Jon Gudnason passed along another quick answer........

What a great picture! John Rebenstorff would perhaps be most qualified member to comment on this. I don't know if he is on line. I believe it could be the result of two possible conditions or a combination of both. A heat pump has a defrost cycle that involves reversing the flow of refrigerant. This runs hot refrigerant through the exterior coil during freezing conditions to defrost it. The reversing valve that directs the flow may be malfunctioning. I believe that an incorrect refrigerant charge in the system can also cause this condition. I am not sure how.

That is my two cents. Jon Gudnason - Placerville, CA

Finally, our AII™ member expert on Heat Pumps who has already been quoted and referenced added his valuable insights....

This system appears to not work in the defrost cycle allowing frost to build into a solid sheet of ice. It could also be caused from a low refrigerant charge. The reversing valve may have failed. The room thermostat may be broken or damaged. I have encountered this condition many times as an HVAC service technician. As an Inspector recommend a HVAC Tech further evaluate. Low outside air temperature coupled with moderate to high humidity and a faulty system results in the condition shown. ----- The outdoor coil acts as an evaporator in the heating mode, Remember that the indoor coil during the cooling cycle is the same as any standard a/c unit and it acts as a dehumidifier, that is why you have a condensate drain on the indoor section. Well during the heating cycle the outdoor coil becomes the evaporator and dehumidifies- in this case because the outdoor coil temperature is at or below dew point moisture is allowed to collect on the coil in the form of frost. A heat pump utilizes a defrost cycle to rid the coil of this formation. Most are timed defrost cycles either brought on by sensing air pressure drop across the coil or temperature or preset every 30-90 minutes depending on climates expected. The unit comes out of defrost normally by terminating thermostat fastened to the outdoor coil. Most units are shipped with a
thirty minute cam and a 90 minute as a spare part item. During defrost on most units the outdoor fan will also be stopped. Hope this answers most your questions. I offer my HVAC Inspection course at the AII™ Conferences with an excellent handout that also covers heat pumps. I have currently finished a book on HVAC Inspections for the Inspector and am interested in adding these pictures if I could get permission to publish them. I could provide a handout in return. If interested in placing a more thorough article on heat pumps and how they work please contact me.

John Rebenstorff & Associates - Orangevale, CA

Sylvan Stenge encountered another Heat Pump evaluation question.........

Heat pumps....probably my weakest subject. Inspection this AM.... Heat pump appeared to operate fine. Detailed manipulation of setback thermostat beyond my knowledge. Red emergency light off. Amber "supplemental" light on constantly. Return air 67, supply air 110.

Inclined to report "improper supplemental heat operation-Suggest consulting HVAC technician". Probably will add more description of condition.

Ya'alls thoughts? Thanks, Sylvan Stenge - Sacramento, CA

Dan switched the topic thread by taking the time to reinforce our Rules of Thumb for evaluating Heat Pump Systems......

Sylvan, Heat pump sounds ok. Return air = 67 degrees, supply = 110 degrees. (allowing 24 degrees. for heat pump leaves 19 degrees. for heat strips, 67+24+19=110)

Heat pumps can be tricky. Some thoughts on inspecting:

1. If ambient temperature is above 65 degrees, operate in cooling mode. If ambient is below 65 degrees, operate in heating mode.
2. In heating mode, look for 20 to 28 degrees differential (rise).
3. In heating mode, be sure to test w/o heat strips running. Take cover off of two stage (two mercury bulbs thermostat), turn up thermostat very slowly until first stage activates. (second stage is for heat strips). Check for correct temperature differential.
4. To verify operation of heat strips; a) turn up thermostat to activate second stage (heat strips). Verify operation of heat strips by additional rise in temperature. b) second method - run heat pump in emergency mode. Compressor should not be running. Temperature at supply should be warmer than at return.

OTHER NOTES: Sometimes the heat strips have been removed. Sometimes an HVAC tech will install a temperature switch that prevents heat strips from operating until ambient temperature reaches a preset temperature (usually a low temperature.) This is done to save energy because operating a heat pump in the heat strip mode is very costly. Identifying presence of heat strips: I look for separate fusing and/or manufactures spec plate showing heat strip sizes. Usually one can see to separate disconnects one for compressor and one for heat strips.

SIDE NOTE: In heating mode the air off the compressor is colder than ambient air. Because the compressor is now the evaporator your cooling the air outside suction line will be hot. (too hot to touch) Liquid line will be cool.

QUIZ: Inspector Quiz for inspectors in cyberspace-- In the A/C mode, what does the second mercury bulb in the thermostat do?

Hope this helps! Dan Back - Gridley, CA

The compiler of this MMM answered quickly Dan's quiz with......

Doesn't this ring the bell for the Egyptian maidens to bring in the palm leaves to fan you while carefully feeding you grapes??? Michael Leavitt - Orem, Utah

Alright, so my answer was nowhere close...... Then again, maybe it was on target. Dan Back rechecked in and elaborated with the quote of the week........

Michael, You are close, as the answer does have something to do with "fans and cooling"

Quote: "The best tool an inspector can have is knowledge. I'd rather spend a day in school than anytime in court." Dan Back - Gridley, CA

Jim Lucas clarified the 65 degree directive......

Dan, it doesn't matter whether or not you operate a heat pump above or below exterior ambient temperature. of 65 degrees as it has an internal heater (providing it has been on for 12 or more hours). The 65 degrees. It only applies to standard A/C units. Jim Lucas, Camino, CA

Dan Back takes a moment to step back to Heat Pumps 101 to help all of us who don't encounter these systems very often, if at all........

Sylvan, To test heat strips if the thermostat is electronic. First test the heat pump by turning up thermostat no more than 2 degrees, compressor should come on. Then check for adequate temperature. differential. Next, turn the thermostat up, an additional light on the thermostat should come on indicating heat pump + supplemental heat. After turning up the thermostat, your temperature on
the supply side should increase. This verifies the heat strips are working. Second method to test heat strips-- If the thermostat has an emergency mode, flip thermometer switch to emergency mode. The fan should come on with the compressor off. The temperature at the supply side should be warmer than at the return side.

For comments regarding testing the air conditioner when ambient temperature is below 65 degrees, see comments by Jim Lucas. Dan Back - Gridley, CA

Dan Back went on to discuss trouble shooting the Defrost Controls......

Jim Lucas, Your comment that one can run the heat pump in the A/C mode when the ambient
temperature is below 65 degrees is correct. However, it may be difficult or impossible to test the A/C for proper cooling. I would not want to lead one to believe that you can test the A/C under these conditions.

THOUGHTS: This is because during cold ambient temperature (below 65 degrees) the condenser gets too efficient. The condenser has more liquid than gas as it would under normal operating conditions... and then the system would act as though it were low on refrigerant. And one might not get an acceptable cooling temperature differential. Therefore, it is best to test the heat pump in the heating mode when the ambient temperature is below 65 degrees.

By the way, for those that insist on testing an A/C system (not a heat pump, but you could although it would not be prudent), here is the method and it does exceed our standards.

(WARNING: The following paragraph is not endorsed or recommended by AII™.... Michael Leavitt)

Go to your pickup truck, grab those garbage bags and start covering the condenser. Keep covering until the liquid line is just about luke warm; warmer than the ambient temperature. You may have to cover quite a bit of it. Then check for the acceptable split (temperature differential at the Return Air & Supply registers).

Incidentally, for Ken's condenser freezing, it would have been a good idea as well as an acceptable practice to operate the heat pump in the A/C mode. This is what the system is supposed to do anyway... that is to automatically go into the A/C mode to melt the ice. By switching from the heating mode (cooling the outdoors) to the A/C mode (warming the outdoors), one would be able to test if the reverse valve was functioning, thereby eliminating it as one of the probable causes for the inoperative system. In all likelihood it is my understanding that the most likely cause of freeze-up is a defective defrost control. The two common defrost controls are:

1) The demand-defrost which uses sensors to determine when a defrost cycle is needed.
2) The time-temperature defrost which activated the defrost cycle at preset intervals when the outdoor temperature drops below a specified level.

Dan Back - Gridley, CA

Dan Back the rechecked in to follow-up on his initial Inspector's Challenge.....

We did not get a correct answer, although Michael was close. The answer. In the A/C mode, the second mercury bulb in the thermostat activates the high speed fan in the blower. This is for faster cooling but less energy efficient. Just like when operating a heat pump in the first stage is more efficient because the heat strips are not activated. With A/C once the interior has cooled to the setting on the thermostat and as the temperature rises the A/C will come with the fan at the low speed to save energy. If the thermostat is moved to a high setting, this calls for rapid cooling and the second stage higher speed of the variable fan motor is activated.

INSPECTOR QUIZ #2 - Inspector Quiz for inspectors in cyberspace- we have all been trained to report the condition of the A/C condenser not being level.

QUESTION: How many degrees unlevel is acceptable.

HINT: The Egyptians knew this when they built the pyramids. They wrote it in hieroglyphics and on paper from the papyrus tree. The Babylonians also new the answer to this and they wrote it in their language...cuneiform. Dan Back - Gridley, CA

MARKETING TIP

The MMM would not be complete without a marketing tip to help increase your visibility and business success. This week's marketing tip was inspired from my channel surfing late at night as I came across one of the many COPS type shows. I watched the Sherrifs raid a home and as they did so there was no mistaking who were the Sherrifs and who were the plain Joe civilians and/or bad guys. It seems that all of the law enforcement agencies use the same technique to identify themselves for the entire neighborhood to see.

Law enforcement agencies attire their home entry raiders with dark jackets sporting huge yellow letters across the back saying SHERRIF. This keeps them from shooting one another, and lets the neighbors know who is making the raid. What a great idea! I had recently received a navy blue jacket as a gift from my wife with the intention of having my small 3"x3" logo embroidered on the upper left front portion of the coat. COPS inspired me to talk with my local Embroidery Magic shop to see what it would take to blow up my logo to fit on the back of the jacket.

My shirt pocket embroidered logo ran $125 to have the graphic computerized and then $3 per shirt after that. I was fearful what fee for the huge version would run. It turns out that it was only an additional $10 for the computerization upgrade. What a deal!!! My small logo incorporates 7,842 stitches to complete. Measuring 12" x 12" the larger logo uses 43,688 stitches....... Wow! It is quite impressive though and worth every cent of the $16 for each article of clothing that I have it placed upon in the future.

Now when I am walking around the exterior of houses and climb on rooftops the whole neighborhood will know who I am......... If you want to increase your businesses visibility you should consider this form of visual marketing.