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Bethany United Methodist Church Building Information

This packet was intended as a reference to the building's main systems, most importantly HVAC. The heating system is very complicated, and nobody else in the building fully understands how it works. The information allows anyone to troubleshoot problems with the building's mechanical systems. It also provides methods for maintaining proper, efficient operation, hopefully saving the Church money in the long run. Virtually all the information was put together by exploring the building. The only information available was a basic diagram of the thermostat system and the blue prints. None of the blue prints gave any information on the specific systems in the building.

 

 

HVAC System

Furnace

Boiler

Thermostat System

Thermostat Control Panel

Thermostats

Air Conditioner

Exhaust Fans

Other HVAC Information

Furnace:

General Info:

The old portion of the building is heated by the furnace, which is located under the Narthex and Sanctuary. There are three burners in use, and all of them must be operating during weather that falls below freezing. The fourth burner located in front of the blower chamber is shut down. It was probably used to preheat the air in the blower chamber. However, it is not known where it gets its supply air from.

Operation:

When the thermostat in the Sanctuary calls for heat, all of the burners will come on. After at least 3 minutes (longer if it is very cold outside) the blower will come on. When the furnace is ready to shut itself down, the burners will turn off first. After a few minutes the blower will shut off as well.

Trouble:

If the Sanctuary is not as warm as it should be, one of the pilot lights might be out. To see if this is the case, look along the burners right under where the supply air enters the heat exchangers. When they are lit, blow some dust off the floor, it will turn the flames bright orange. If there are only two thin rectangles of light, one of the pilot lights is out. Most likely, the middle of the three burners is out. Follow these instructions to relight it:

Turn off the main power. The switch is labeled and is on the north wall, to the left of the hot water heater.

When the blower is off, open the main air supply panel.

Crawl inside, and use a socket wrench or a pair of pliers to open the panel.

Push in the control knob on the gas valve and turn it to Pilot.

Push the knob as far in as it will go (do not let go until the pilot has been lit for 30 seconds) and light the pilot from above the burner assembly (see the diagram below).

Turn the control knob to On.

Replace the panel, and make sure the gasket seals it from any air movement.

Close the main access panel and flip the main power back on.

If it is very cold outside (below 0°), and the furnace is operating erratically, there is probably cold air inside the blower chamber. Make sure the furnace is trying to run (the burners will be cycling on and off, but the blower will not be running). Turn the small switch that is marked Auto/Fan On to Fan On. The blower will start, and all the burners should light up. Leave the switch on for about 5 minutes, this will allow enough time for the air to circulate a number of times through the system. Turn the switch back to Auto after 5 minutes are up. If the blower turns off, wait until it turns back on by itself before leaving.

Cooling:

The furnace can be used to cool the Sanctuary to a certain degree. Try this only if the temperature in the Fellowship Hall is significantly cooler than the Sanctuary. In the Furnace Room, turn the Auto/Fan on switch to Fan On. Open the door to the blower chamber and prop open the door to the Furnace Room. In order to make this useful on hot Summer days, the Sanctuary windows must stay closed. Also, make sure that the door to the North Stairwell is closed. It is extremely important not to leave the blower on after services are over. The blower draws a huge amount of electricity, and it will drive up the electric bill if left on.

Special Notes:

The thermostat in the Sanctuary should not be turned below 50° during the week.

All 3 ceiling fans in the Sanctuary should be turned to medium when the heat is on.

Do not remove the plastic covering over the outside vent which supplies fresh air to the furnace. If the covering is removed, there is not enough hot air to heat the Sanctuary on cold days. Also, it causes problems with the blower (see the Trouble section above).

The blower's main power shut off is on the east wall above the Auto/Fan On switch. The access panel cannot be opened until the power is switched off.

Do not close the return vent in the old Organ Blower Room (behind the Storage Room which is next to the Men's Bathroom on the bottom floor).

Boiler:

General Info:

The boiler operates somewhat separately from the building's thermostat system. The water inside of the boiler is kept at roughly 200°F when it's turned on. There is a cut-off switch on the north side of the boiler, it should never be changed. This turns the main burners on when the temperature falls below 180°, and off when it reaches 200°. The burners have two stages of fire. The first stage fires under normal operation. However, if the boiler temperature falls too far below 160° the second stage will light. The second stage is the burners located along the sides of the burner chamber. The second stage may not work, however, because it is almost never used and it may seize up. This is not really a problem, because the second stage is only necessary when the boiler is first started up in the Fall. The boiler will continue to maintain the same temperature even in the middle of Summer. Therefore, it must be turned off for the warm months of the year (see the Shutting Down section below).

Operation:

When the boiler first comes on, the draft fan will start up. This will cause the draft damper to close completely. After about 20 seconds, the electronic ignition will start the burners. When it turns off, all components shut down at the same time, and the draft damper will slowly open.

Trouble:

If the draft fan is not running, do not shut the boiler down unless there are obviously fumes leaking from it. As long as the draft damper is working properly, there is no immediate need to shut down the boiler. Check the Draft Fan Motor switch underneath the Boiler Power switch. Make sure it is on, and if the burners are lit, flick the switch off and on to make sure it is not just a one time problem. If this does not work, check the motor itself (it is located on the south side of the boiler). Chances are that the motor is burned out. It should be replaced as soon as possible by a qualified technician. If the electronic ignition is working but the burners won't light, push the green button to the left of the Boiler Power switch.

Mixing Valve:

Once the water leaves the boiler, it is entirely in the hands of the thermostat system. Just to the south of the pump is the water mixing valve. When the valve is closed, the water is simply pumped straight from the return water line back into the supply line. When the main water temperature falls below its setting, the valve opens and lets the very hot water from the boiler mix with the hot water in the system. The temperature is increased as the outside temperature decreases (see the Thermostat Control Panel section below).

Shutting Down:

At roughly the beginning of June, the boiler should be turned off. This helps save money, because the boiler normally continues to run even on very hot days.

Turn off the Boiler Power switch on the side of the boiler.

Turn off the circulating pump. The switch is labeled and is located on the south wall.

Turn off the air compressor (only if the air conditioner will not be used over the Summer). The switch is labeled and is located on the east wall.

Disengage the 7 day clock. Simply loosen the nut that attaches the disc to the motor. Make sure that the disc rotates freely, and that the system is set on day. This stops wear on the solenoid valve.

At roughly the beginning of October, follow these instructions to start the boiler again (Note: The boiler and furnace should be serviced at this time):

Reset the 7 day clock, and tighten the nut on the disc.

Turn on the air compressor, wait about half an hour before proceeding beyond this point. Go ahead if it's already on.

Turn on the circulating pump.

Turn on the boiler.

 

Thermostat System:

General Info:

This is the most complicated system in the entire building. Once understood it seems fairly straight forward, but it takes a long time to figure out. Basically, the building uses a pneumatic thermostat control system, meaning all thermostats, and most of the control panel, use compressed air to operate. The diagram below details the setup of the pressure switching apparatus. This system is designed to switch the main air supply pressure to 15# during the day and 20# at night (Note: # denotes air pressure in PSI). The diagrams posted next to the main control panel (which were used during construction), are not entirely correct, the diagram below is correct. According to the old papers, the N.C. line is 15# and the N.O. line is 20#. In fact, the system is set up in reverse. This also means that the solenoid air valve is energized only at night, not during the day as the old diagram states. During normal day operations, the system works as follows: The 60# air leaves the compressor and branches off between the N.C. lines and the N.O. lines. The air then passes through both pressure reducing valves. The air in the N.C. line is blocked by the air switching valve. The solenoid valve and port Z on the Day Auto Night switch are also closed. Basically, there is nowhere for the 20# air to go. The 15# air in the N.O. line makes a 90° turn at the air switching valve and exits through port C. to the building.

Switching:

There are two ways to switch the system between day and night settings. The manual way is to turn the Day Auto Night switch between day and night. When the system is switched manually to night, port Z connects with port W on the Day Auto Night switch. This switches the air being allowed through port C. from N.O. to N.C. on the air switching valve. When the air switching valve is in the night position there is a pressure buildup in the N.O. line. The pressure climbs maybe 2 or 3 PSI. This is a problem, because it causes the pressure reducing valve to vent the excess air. When this happens there is the potential that the system could lose enough air to cause the compressor to run constantly. Also, because the pressure reducing valve is old the pressure may not fall back to 15# on its own after the day setting has been established. This valve should be replaced soon to prevent any problems in the future. In an attempt to postpone the problem, the 15# valve has been changed to 13#, and the 20# valve has been changed to 22#. This will help the 15# valve fall back to its proper setting, and it will also help switch the thermostats a little better.

The way the thermostat system was intended to run is in the auto mode. Set the Day Auto Night switch to Auto in order to operate the system in this manner. When set at auto, the system switches itself between day and night according to the settings on the 7 day clock. Currently, there are not enough pins on the clock to operate a day/night cycle for every day of the week (Note: Each pin can be either a day or night pin. Just remove the thumb screw and put it back in the opposite hole to change its function). When the clock tells the system that it is daytime everything works exactly as it would if the Day Auto Night switch was set manually to Day. When the clock tells the system that it is nighttime things get complicated. The clock energizes the solenoid valve, thus allowing the 20# air to flow through it. The 20# air travels through the Day Auto Night switch from port Y to port W. This changes the position of the air switching valve, and thus allows the 20# air from the N.C. line through the valve's C. port and to the building.

Thermostat Control Panel:

General Info:

The air pressure system can be viewed as a progression from the N.C. line to the hot water supply temperature. Use the diagram above as a guide. The air first branches off of the N.C. line right after the pressure reducing valve. It then goes into gauge 6. This air then goes over to gauge 4 and to the outside thermometer (the outside thermometer is located over the door leading to the Parking Lot from the landing in the Basement Stairs). After the air pressure is reduced by the thermometer it proceeds through dial 1 to the outside air remote set point 9. It should not be changed. It sets the relationship between the outside temperature and the pressure reading. Currently it is set so that when the temperature is 60° the pressure is 15#. At 15# the system turns off the circulating pump, but cannot turn off the boiler. After leaving the outside air remote set point, the air goes through gauges 5 and then 7. After that, the air goes into the water supply remote set point 12. This remote set point changes the relation between the air pressure and the water supply temperature (it has the same function as 9, it is just older). After that, the air goes through gauge 8 which registers the pressure to the water mixing valve (see the Mixing Valve section on page 3). The air then goes to the mixing valve itself. When the reading is 12# the valve is closed, allowing no boiler water into the supply. When the pressure drops, it lets in water from the boiler into the supply line. Gauge 10 simply registers the pressure that is acting on the air switching valve. It will read 0# during the day and 20# at night.

Thermostats:

General Info:

The building contains 22 Johnson Controls pneumatic thermostats. Of those, 7 are not made to switch between day and night temperatures. They are located in the top and bottom of each stairwell, in the Dubs Room, and in the two downstairs bathrooms. The model number of these thermostats is T-4002-201. The rest of the ones in the building are dual acting and can switch between day and night. The model number of these thermostats is T-4502-201. The T-4502s are rather complicated. These thermostats are most "comfortable" when in the day setting. Most of the thermostat's components are right on the front. Looking at one of the T-4502's, there are 2 metal strips (the T-4002's only have 1). These are the bimetallic strips which sense the changes in temperature. The one on the bottom (3) is the day strip.

Operation:

Behind the very left end of each of the bimetallic strips is a small metal tube, this always bleeds a tiny amount of air to sense the movement of the strip. When the bimetallic strip bends away from the tube (which means the room is getting cold), the strip lets the air out. When the air is let out, the thermostat lets all of the air out of the air pipe between itself and the radiator valve. When the air is gone, the valve opens and hot water starts to flow through the radiator. When the room warms up and the bimetallic strip touches the tube, the opening is blocked. When the tube is blocked, the thermostat lets the air flow through it and forces the radiator valve shut. Not all of the thermostats operate quite like this though. The older ones are slow, and they gradually open and shut the valve. Some of them fluctuate between slightly open and more open which is more comfortable, but means the thermostat is somewhat clogged. There is no need to replace any thermostats that do this, however they will be the first to fail.

Calibration:

As of the '96/'97 heating season all of the thermostats have been properly calibrated so that the rooms stay at a comfortable temperature. The calibration screws are the ones on the far right end of the bimetallic strip (5 and 6). If recalibration is necessary, only turn the screws a tiny amount (no more than 10°). The calibration screws are extremely sensitive, and it may take a few hours before the new temperature is reached. All of the bottom strips are calibrated for a comfortable temperature when set at 70°. The top strips (2) are calibrated for a night temperature of between 55° and 60°. Don't turn the screw that sits in between each of the bimetallic strips (7), this just throws the calibration completely off.

Setting Night:

The best way to set the night temperature is to turn the system to night and set the temperature right away. Simply turn the temperature dial between 80° and 85°. After setting the dial, turn the calibration screw on the top strip until the thermostat responds. After the temperature is set, turn the dial back to 70°.

Buttons:

The buttons on top of the T-4502s (1) are not very useful. They will switch that particular thermostat to the day setting if the system says it is night. However, the button must stay down or else the night temperature will be reinitiated. Using a few rubber bands will hold down the button, but they must be removed or else the room will stay at day all the time.  The button should also reset the thermostat to day if it happens to be stuck on night.

Trouble:

There is one good way to check if the thermostats are operating properly. Follow these steps when the system is at day and also at night:

Using the Johnson Controls Allen Wrench (found in the Supply Closet on the Main Floor), pull both bimetallic strips away from their sensing tubes. Place the wrench behind the thick side of the strip (4) and pull forward gently. Never touch the thin part of the strip, they are very sensitive.

Cover the bottom hole with your thumb and listen for any hissing.

Cover the top hole and listen for any hissing.

Slide the Allen wrench away from the strips carefully.

During the day, if covering the bottom tube causes a reaction and covering the top one does not, there is no problem. At night, only the top strip should be active.

If they both cause a response there is only one way to possibly fix it. Use the Allen Wrench to take the thermostat out of the wall. Have a dull pencil ready to plug up the left hole in the wall. Turn the large screw on the back of the thermostat no more than 180° at a time in either direction. Replace the thermostat on the wall, and repeat steps 1-4 again. If it does not work keep turning the screw, but do not let it get too loose, there is a spring behind it and it will fly across the room and get lost. Also, if it is getting too loose and nothing happens, try tightening it instead. If the response is corrected, cycle between day and night a few times to make sure it will work fine on its own. This however, rarely works so replacement might be necessary. A new T-4502 costs close to $100.

Special Notes:

Of all the thermostats in the building, only 7 of them work well enough to switch between day and night. These thermostats are in all of the classrooms on the top floor, and in the Fellowship Hall. (Note: The one in the Kitchen does switch to night, but the air tube is smashed so it shuts off completely at night). The thermostats that do not switch are on the Main Floor. They do not need to be replaced at this time, because none of those rooms should be colder at night. All of the classrooms have either plants, fish or animals that would die if it got too cold. The 3 offices should stay warm all the time too so that anybody can work during off hours.

Air Conditioner:

General Info:

The 3 offices and the Storage Room on the Main Floor are serviced by a central air conditioner. This is the original air conditioner installed in 1964, but it can still work if properly repaired. The air conditioner worked fine in the fall of 1997, but hasn't worked since. The compressor won't start. It uses a water cooled condenser instead of a large unit outside the building like most residential air conditioners. Therefore, there will always be water flowing when the unit is cooling. The plastic cup and tube must not be removed from the drain, or else it might leak into the Fellowship Hall below. The Damper switch will not register until the circuit breaker is turned on, and the thermostat that controls it is the one in the middle office. The damper mixes return air and outside air, the lower the air pressure reading, the more air is recirculated. Turning the damper as high as it will go brings in virtually all outside air. There is rather little air flow throughout the system, however this appears to be normal.

Operation:

Follow these instructions to start the air conditioner:

Make sure the air compressor in the Boiler Room is on.

Adjust the thermostat in the middle office to about 78°.

Make sure the left knob in the control panel (on the bottom right of the unit) is turned all the way to the right.

Turn on circuit breaker #32 in the panel to the right of the air conditioner.

Make sure the damper control knob is set to 0#.

Close the office doors.

When the circuit breaker is turned on, the fan will start up. If the office is warmer than the set temperature the compressor will start after about 2 seconds. Soon after that, the water will start flowing through the condenser. The water might stop flowing for a second or two, but this is normal. The condenser water flows out of the copper pipe and the condensate from the evaporator coil drains out of the large galvanized pipe. As long as the circuit breaker is on the fan will keep running. There is an air filter in the middle compartment of the air conditioner. This should be checked at the beginning of each cooling season, and replaced if necessary.

Exhaust Fans:

There are 2 exhaust fans in the building. The first is located in the Boiler Room. It pulls air out of the Fellowship Hall through 3 large vents. There is also one in the Dubs Room as well. The switch for this fan is located at the end of the duct in the Boiler Room. It is to the right of the access panel facing the south wall. Before using this exhaust fan, open the 3 large vents with a screw driver (there is a screw in the corner of each vent that opens and shuts it). These vents have to be shut in the Winter, otherwise cold air flows into the building.

The other exhaust fan services all of the bathrooms and Janitor's Closets on the 1st and 2nd floors. The fan itself is located on the roof of the building, and as of January 1999 is still inoperative. Tom Danley is supposed to be working on the motor.

Other HVAC Information:

The building's gas meter is located in the old Coal Room under the front steps.

There is a forced air convector at the bottom of the North Stairwell. This should be left at the low setting always. The fan turns off if the water supply gets cold so there is no need to turn it off.

There are 2 forced air convectors in the ceiling of the Kitchen. The one by the door to the Playground works sometimes, and it will only run on High. The other one is completely inoperative, the motor has seized up. Replacing the motors would be very difficult and costly, and the extra heat is not really needed.

There are two radiator valves in the building that need replacing. The first is in the Dubs Room. The valve is located next to the door and does not close. To keep it from getting too hot the water valves on either end of the convectors have been partially closed. They should not be reopened until the valve is replaced.

The other broken valve is located in the northwest classroom on the Main Floor. The valve is against the west wall near the sink. The water shutoff valve has been almost completely closed. That valve is in the middle of the west wall near the two pipes that go up to the ceiling. The convectors under the north windows operate normally since they have their own control valve.

Whenever it rains substantially, the pit that the furnace is located in floods. The water should be pumped out as soon as possible because there is a serious rust problem down there. The water appears to be leaking into the old Coal Room from the side of the front steps (by the gas meter).

The Thermostat System should be drained of excess water every month. The two drains are labeled on the diagram above.

Electrical System

Main Electrical Panel

Location of All Circuit Breaker Boxes

Timers

Switches

Power Outages

Emergency Lights

Main Electrical Panel:

The building's main electric service enters from underground. The power comes off of one of the telephone poles out in the Parking Lot. The power comes in under the double doors which lead out to the Parking Lot. The main panel is located in the Boiler Room on the west wall. None of the components are to be touched by anyone other than an experienced electrician. The main power shut off and the electric meter are located here.

Location of All Circuit Breaker Boxes:

Boiler Room:

There is one fuse box located to the left of the Fire Alarm Control Panel. This fuse box controls the emergency lights and Exit signs throughout the building.

Basement:

There are two breaker boxes in the Storage Room next to the Men's Bathroom. The one on the left controls the old portion of the Church (Sanctuary, Narthex, Vestibule, Choir Room, WSWS Office and Balcony). Few of them are labeled, and they are not shown on the electrical plans. The breaker box on the right is for the downstairs rooms to the west of the Furnace Room. All the light and receptacle breakers for the Fellowship Hall are labeled. The rest are labeled as well, and refer to the electrical plans.

Main Floor:

There is one breaker box in the Air Conditioner Room. This controls all lights and receptacles on the Main Floor in the newer part of the building. They are labeled, and refer to the electrical plans. The breaker marked Outside Porch Lights is the only known way to turn the lights on the porch outside the Fellowship Hall on or off. The breaker marked A/C should stay off when the air conditioner is not in use (see the Air Conditioner section above).

2nd Floor:

There is one breaker box in the Janitor's Closet (next to the Boy's Bathroom). Most are labeled and refer to the electrical plan.

Timers:

Basement:

There is a timer in the Storage Room, by the Men's Room. It controls the outside bulletin board that faces Laurel Ave..

There is a timer in the furnace blower chamber. It is marked on the outside of the metal wall. This controls the outlet next to the front steps, by the gas inlet.

Main Floor:

There are two timers in the Air Conditioner room. One of them controls two lights on the top of the west side of the building. Both lights are broken, and need not be fixed. The other one controls the outside lights by the Parking Lot.

2nd Floor:

There is one timer in the south-east corner of the balcony. What it controls is unknown.

Switches:

Basement:

There are two switches right at the entrance from the Parking Lot. The one on the right controls the lights that must stay on constantly in the halls and stairwells. What the other one controls is not known.

There is a switch inside the closet in the Fellowship Hall (on the right side on the west wall). It is supposed to control the exhaust fan in the Boiler Room, but does not.

In the Furnace Room there is a switch on the south wall against the chimney. What it controls is unknown.

Main Floor:

In the Air Conditioner Room there are switches for the hallways and bathrooms. There is also a switch for the bathroom exhaust fan.

Emergency Lights:

Exit Signs:

There are a number of old Exit signs from 1964 around the building. They do not last very long, and new bulbs have to be soldered into the light casing. To access it, just take the cover off, and pull the casing out of the fixture (it just plugs into a regular outlet).

There are 2 newer Exit signs that have emergency lights. They should be tested every month, and the bulbs should be replaced as needed.

North Stairwell:

There is an emergency light in the North Stairwell. It should be tested along with the 2 Exit signs.

Plumbing System

Various Information:

Main Supply:

The building's main water supply enters in the Women's Bathroom next to the Furnace Room. The main water shutoff is also located there. The water meter is underground on the parkway near Laurel Ave..

Spigots:

There are various faucets around the perimeter of the building. All of the newer ones need a special faucet handle with a square female connector to operate.

Water Heater:

The building's water heater is located in the Furnace Room. There is a pump on one of the hot water lines which appears to be inoperative. This water line is the one that leads to the Kitchen.

Sewer:

The building's sewer exits to the street from within the Boiler Room. There is a sewer clean-out in the bottom floor hallway near the drinking fountain. Where this clean-out leads is unknown.

Drinking Fountain:

The drinking fountain on the bottom floor would work if someone could find a new button for it. Westinghouse stopped making those drinking fountains long ago, and they cannot replace it.

Urinal:

The urinal in the 2nd floor Boy's Bathroom probably needs a new flush valve. The old one will not close off the water. There might be a problem with the pipe too, because there is very little water flow.

Fire Alarm System

Main Panel:

The main fire alarm control panel is located in the Boiler Room. This panel can only be opened by the Highland Park Fire Department or the company that installed the system.

Auxiliary Panel:

This panel is located on the landing of the Basement Stairs. It will start to screech if there is trouble with the system. There is a Trouble Silence switch that will turn off the siren. However, the system should be serviced if this happens.

Routine Maintenance

Weekly Maintenance:

HVAC System:

*VERY IMPORTANT* Check the furnace pit for water. If there is more than a half inch of water, it should be pumped out.

In Winter, check that all 3 of the furnace's burners are working. Relight any if necessary.

In Winter, make sure that the Sanctuary thermostat is turned down after services are over.

In Summer, make sure that the blower is not left on if it is being used to cool the Sanctuary.

In Summer, make sure that the air conditioner is not leaking into the Fellowship Hall below. Make sure that the plastic cup and tube are still set correctly in the floor drain.

Electrical System:

In the event of a power outage, the following tasks must be attended to.

*VERY IMPORTANT* The timer for the boiler must be reset.

All the timers that are in use must be reset.

The clock hanging from the balcony must be reset.

Any other clocks in the building should be reset, unless the BECLC teachers will do it in their rooms.

Monthly Maintenance:

HVAC System:

*VERY IMPORTANT* Drain the thermostat system of excess water. The drains are labeled on the thermostat system diagram.

In Summer, run both the furnace and the boiler for about 5 minutes to burn off any dust and keep them from seizing up.

In Winter, check all of the rooms serviced by the boiler to make sure that none of the thermostats are stuck at night. Also, turn the system to night, and check that all the thermostats that are supposed to switch are working.

In Winter, make sure that the boiler, draft fan, circulating pump and air compressor are all working normally. Be sure that the 7 day clock is set at the right time.

Electrical System:

Test all emergency/Exit lights.

Seasonal Tasks:

HVAC System:

Every Spring, shut down the boiler as explained earlier, then go set the thermostat in the middle office to 78°. Run the air conditioner for 5 minutes to make sure it is working and not leaking into the Fellowship Hall below, and replace the filter if necessary.

Every Fall, the furnace and boiler need to be serviced. Have the technician come to prepare and start the boiler. This way, any problems can be fixed immediately. The boiler should not be started up before the technician comes, because the burners can't be cleaned while the boiler is hot. Make sure that the expansion tank is drained at this time too. The air conditioner should be shut down, and the thermostat in the middle office should be reset to 70°.

 

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