What kind of "system" is being discussed here? With gas heat and typical cooling maybe a humidifier running in the winter, once a year is fine. Even with oil-fired heat, yearly PM is standard.

Hello! It is best to have two maintenances a year - one on the air conditioning and one on the furnace. This ensures everything is working properly and also protects against a pricey repair later on. Performing maintenance will also extend the life of your unit and can help lower utility costs.

Mike,

Is there an argument for performing the Cooling check when the outside temperature is above, say, 80 Deg F? Also, is it true that outside temp is not an issue in performing a Furnace Check?

I do both of my checks in the warmth of summer for those reasons. Just curious if there was actually a reason to do it that way?

PS My Service folks want to check the A/C in the early Spring - leaving their Techs free for repair calls during hot weather.

TIA

There should be no issue doing the AC condenser PM when the temperature is above 80 degrees. I don't see a problem if a gas or oil furnace is checked in the summer. HVAC companies love to do maintenance during the slow parts of the year.

Mike,

Thanks. Actually I'm asking if the A/C check needs to be done in warmer weather to allow Coolant Measurements to accurately indicate the state of charge. In other words, should I not do it when the outside temp is in the 50s or 60s?

I come from heating only land. In the olden days, fuel oil and heating companies had staff driving delivery trucks in the winter and doing repairs when needed, obviously. The same people did PM and installations in the summer. PM in summer months was SOP for boilers and furnaces.

You should not run the condenser in AC mode when the temperature is in the 50s. Doing so may damage it. Even if the manufacture states low temperature operation is allowable, then the readings will be off and the typical tech may not know how to interpret them. Your best bet is to do the maintenance in the summer.

Thanks. I'll continue doing both in the heat of summer.

I agree with what you said Mike but I think by default you might have indorsed contracts. Some contracts might be ok but the majority aren't good investments. One drawback is they send the greenest kid on payroll out to do contract maintenance. Another drawback is that if you experience a problem shortly before your scheduled maintenanace. The system is checked over at time of repair(or should be if tech does what he should) then again at scheduled maintenance. And vs vs of course. The worst part is I can't count times I went on a cooling complaint and found condensers that had not been cleaned in years,much less a month or two earlier at seasonal maintenance. Pm at begaining of cooling season then again before heating season is a waste for heat pumps. It's to one's advantage being able to shop for specials rather than being tied to a single company. Just another opinion for consideration.