Reasonable HVAC repair costs?

This is going to be a bit vague, but I’m hoping it might be useful.

We are having a technician look at our condo’s heating and air-conditioning unit tomorrow. It needs to pass an inspection, but also will need some work.

The unit is in a closet on the balcony. I do not know many details about it, but I know it uses chilled water from an outside supply piped into the entire condo association.

It currently works. But…

[li]I have been told “the solenoid is broken” and “You may need a new motherboard” by a the condo association’s handyman.[/li]
[li]The metal duct leading the chilled air into the condo is rusted through in a few places. I taped it up with duct tape (on an actual duct – go figure!) but I know that’s a stopgap.[/li]
[li]The cinderblock wall beside the unit has dark smudges on it.[/li][/ul]

Since it still functions with the “broken solenoid,” it’s remotely possible that the unit needs as little as a new metal duct. I don’t know how much that would cost, but it can’t be that big a deal, can it?

The flip side is that my spouse has declared that the smudges on the wall are “mold.” She has a fear of “toxic mold,” reinforced by all the people who want to sell us stuff, and she believes having the work done will run into many thousands of dollars, including mold remediation.

She will be the person staying home to talk to the tech tomorrow.

I am hoping to gather some experiences and/or technical knowledge in this thread that will arm me to avoid being miserably ripped off in the decision of what to pay for. I know it’s a longshot.

Our location is Northern Virginia, and cost-of-living is fairly high here.

For all I know, the smudges could be toxic mold. Or regular mold. Or mildew. Or soot. I am concerned that my spouse’s reaction will cause dollar signs to light up in the eyes of whoever does the inspection.

For history, we did once have a guy come over to look at the jammed kitchen garbage disposal, and she paid $525 for a new one without blinking.

But maybe she’s right, I admit to knowing nothing about HVAC and little about home-repair costs in general. Perhaps I’ve been spoiled by having a good auto mechanic who is conservative about spending my money, or maybe I’m just cheap.

Sorry to be so non-specific…I just learned today, after leaving the house, that this was happening, so I didn’t even get to look for a model number.

I live in Tysons Corner, but I don’t think that will help you. The type of cooling you have sounds unusual to me, but it wouldn’t surprise me if the unit caused condensation around it that might develop some mold or mildew. I’m guessing the solenoid is triggered by a thermostat and acts as a valve, but that’s a wild guess. Maybe “broken” means “it never turns off.”

Your best bet is to get 2-3 estimates, depending on whether you find a company that will do a free estimate. If you PM or email me I’ll tell you who I use.

Take a spray bottle, add some bleach solution and spray the mold, problem with mold solved. It is a cinder block wall, mold causes problems in drywall and materials like it. Might take a few applications, might have to scrub it but it will come off. Alot of the “Toxic Mold” stuff is a scam, if you are worried about it, get a mask.

Hopefully your solenoid is cheap(they often are)


By the way, never use “duct tape” on ducts. There is all-metal tape that is vastly better for patching ducts.

Seconded on Capt Kirk suggestion of diluted bleach. If she is still worried, re-paint the wall with Kilz as a primer.

Well, we got the HVAC and the plumbing inspected for $188.

The HVAC did not pass – the rusted-through part that I thought was a duct leading into the condo turns out to be the flue, leading combustion products out, and it’s a carbon monoxide hazard when the gas furnace is running. The tech turned off the gas for safety, so I guess we have “until it gets cold again” to fix the flue. (We do have a working carbon monoxide monitor, recently tested.)

We’ve been quoted for the following possible services:

[li]Replace “zone valve” and wrap the pipes that bring chilled water in (they’re sweaty and could use insulation): $485[/li]
[li]Replace flue (carbon monoxide hazard): $225[/li]
[li]Wrap duct leading air into the condo: $185[/ul][/li](Currently said duct is unwrapped, but has old insulation draped over it, hanging down.) Not sure what the “zone valve” is – possibly the same thing as the “solenoid” we were told was “bad?”

Note that, although it’s a worthy goal, insulating will not save us any actual cash on utilities, as we pay a fixed amount to the condo association every month.

Do these prices seem reasonable? We are going to look for a competing firm or two to do some estimates as well.

Yes. The lack of insulation meant that condensation formed on that chilled water pipe, which is what likely caused the flue to rust. Do not mess around with not replacing a rusted flue - it can kill you.

The amounts seem very reasonable. The “zone valve” is most likely a solenoid that opens and closes a valve.

They should also check the roof to make sure there is a vent cap on the exhaust. If it’s missing, that is a route for water to come in and rust the vent.