Q. Every spring companies advertise clearning of dirty air ducts in homes. They assert that the duct accumulate dust, and mold, and cleaning them reduces allergies. Is there any truth to this. Our house (30 yrs. old) has never had its "ducts cleaned." Please advise.

A. Many people do not realise the importance of cleaning fan coils and duct work. Although it may seem things are OK, you are potentially breeding harmful bacteria and may be suffering the side affects without knowing it. If not maintained, bacteria can build up within air conditioning coils, leading to flu like symptons, sick building syndrome and fatigue. I have put a page together here that will provide much more detailed information: http://www.ampleair.com.au/air-conditioning/Service-Maintenance/Domestic-Maintenance/Aeris-Guard-Anti-Bacterial-Treatment-Service.html Regards Jon http://www.ampleair.com.au

Q. Repairs by Tenant: Tenant shall keep by routine maintenance, repair, and replacement, at its sole cost and expense, the interior of the Premises, together with the storefront and all doors and windows of the Premises, and all electrical, plumbing, and any other mechanical installations serving the Premises or located therein, whether or not in or under the floor slab or on the roof of the Premises, in good condition and working order. Tenant agrees to employ a suitable contractor to perform Tenant's obligations for maintenance of the heating, cooling and ventilating units of the Premises, including at least semiannual inspections and cleaning of the system together with such servicing as each such inspection shall disclose, or as shall otherwise be reasonably required by Landlord. In the event Tenant fails to perform its maintenance, repair, or replacement obligations as provided herein, Landlord may, at its option, perform such remedial action on behalf of Tenant, and Tenant agrees to pay to Landlord, as Additional Rent, the cost thereof plus fifteen (15.0%) percent overhead promptly upon demand by Landlord. Georgia

A. The landlord is responsible for all major repairs. If the unit is bad, that is not considered maintenance.

Q. I work in the Philippines where most of the window type air conditioning systems have no ports for adding refrigerant. There is supposedly a pinch connector you can use to puncture the line for servicing. The pinch remains in the line permanently. Where can I find more information on this adapter or pinch for servicing or recovering sealed A/C systems?

A. Bolt on service ports are available through most HVAC supply houses in the USA. These work well for recovery, but tend to leak if left in a system so I won't put them in anything that's going back into service.

Q. Should I withhold rent if this is not addressed within 1 month?

A. No, it is not regular maintenance. It is not required at all. You can not legally withhold for this, and the landlord is not obligated to clean the ducts. Clean them yourself if you are in a tizzy about them.

Q. As a happy homeowner with no technical knowledge what should I do for preventative maintainence.

A. About the only thing you can do as far as doing a P.M. on your system,make sure its clean(coils) this is for the condenser,make sure there is nothing blocking the airflow,wash the coils out maybe once a month,just use a water hose make sure you turn the unit off first,wash it out good,make sure there's no grass,debris growing or stuck around the unit,make sure the big copper line is insulated good,as far as the inside unit make sure the filter gets changed once a month and the coil is cleaned and unrestricted as far as airflow is concerned,make sure the rest of your home is checked for leaks(air),nothing worse than having all your cold air cooling down the birds and chipmunks,all the door seals and windows need to be checked for leaks.i commend for taking on the task for doing your on P.M.s you wouldn't believe how much you can catch and repair just doing a simple inspection,that's why they call it preventive maintenance

Q. Is it OK to pour drano or similar products down the pvc drain lines of your a/c unit to keep them clean? Also is there any reason I should not install a "T" PVC joint where the drain lines come out of the unit so that I can do this w/out having to detach the drain lines to do maintenance?

A. You can pour dilute chlorine down the drain, once you have cleared the line. It is possible to blow out the line with compressed air, CO2 or the ole' fashioned tuba method. You can install a clean out T in the line. They now manufacture a cleanable trap with a clear u joint so that you can monitor the drain. I'm not sure if is available at home stores, but you might be able to get one from a local company that installs HVAC equipment AND they sell over the counter. If you go with PVC T, install with the T junction up and add a 6-inch riser. Pick up a tight-fitting cap for the top of the T. Don't use glue on the cap, just snug it up.

Q. I have a friend of a friend (who is an A/C Tech) that has offered to come out and 'top up' my home A/C unit with freon for $200. The air is blowing about 70 degrees but will not cool the house any less than 75. 1) Will this fix the problem? 2) Is that a reasonable deal or am I being taken for a ride?

A. I actually just had someone fill mine up this morning, and it cost $125. (But he cut me a deal, plus we live in a very small town) I'd say that's a pretty fair price. Our entire house has been SO much cooler than it was....before it would only cool it to 80 and my fiance said he fell asleep and woke up and it had cooled to 65. Just make sure that the Freon (sp?) is your problem. It could be the air filter or coils. Hope this helped.

Q. My aunt has not cleaned their air ducts in 5 years(ever since they moved into the house) and they have not been using an air filter since. She lives in northern cali and uses the heater during the winter and the a/c not so much during the summer. I saw the part where the air goes into the duct and it was covered with so much grey dust that i just HAD to vaccum it for her. There were 2 of these. They were both downstairs up close to the ceiling. Their house is 2 story. one was next to the stairs I told them they should buy an air filter because her whole family has asthma including her, but they're scared that the filter might catch on fire! Their youngest son (4) also just recently got asthma after winter. But they dont really get allergies in the house in the summer because they have windows open but its only in the winter when they have the heater on Dont you think they need this or is it just me? Do you suggest air duct cleaning? since its been so long without a filter

A. To give you an idea of how much dirt is in the duct work you can look inside the ducts or supply air runs by removing the diffusers. What you should be more concerned about is the dust that may be attached to the blower wheel and the evaporator coil and if the furnace is High efficiency it may have a secondary heat exchanger that may also plug up. If any of these actually plug right up with dust It may cause the air conditioning to freeze up. What is required is a full heating and cooling planned service maintenance check and cleaning. Many heating and cooling companies have a program in place and will go as called or will sign you up for an annual maintenance. The annual maintenance might be a good idea for them as they will also change the filter regularly. The usual cost of a maintenance program is what they would charge for 1 1/2 -2 hrs labour and any parts that you would need like a filter.