Stuart RV Repair tests and replaces RV AC capacitors on-site across Stuart, FL and the Treasure Coast. Start caps, run caps, hard start kits. The #1 AC repair we do in Florida heat.
Stuart RV Repair tests and replaces RV AC capacitors on-site. Start capacitors, run capacitors, dual caps, and hard start kits. $120-250 depending on the part. This is the single most common AC repair in Florida. We come to you anywhere in Stuart, FL and across the Treasure Coast. Call 772-280-3915. Need a full rooftop AC repair? We handle that too.
If your RV AC hums but won't start, or trips the breaker every time it kicks on, the capacitor is the first thing we check. And 7 out of 10 times in Stuart, that's exactly what the problem is. Capacitors are cheap components that do a big job - they store and release electrical energy to give the compressor the boost it needs to start and keep running.
Florida heat destroys capacitors faster than anywhere else. Inside that rooftop shroud, temps can hit 140+ degrees on a summer afternoon. According to Dometic's technical bulletins, capacitors should be tested annually in hot climates. Every degree above the rated temperature shortens the cap's life. A capacitor rated for 10 years up north might last 3-4 years in Martin County.
We carry the most common capacitor values for Dometic, Coleman, and Advent units on the truck. A swap takes 15-20 minutes once we've pulled the shroud and tested the old one. We also install hard start kits, which add a stronger starting boost to aging compressors. If your AC is over 5 years old and starting to struggle in the Florida heat, a hard start kit at $130-200 can extend its life by several more seasons.
Classic bad run capacitor. The compressor motor needs that initial jolt of stored energy to start spinning. When the cap is dead, the motor just sits there humming because it can't overcome the starting torque. This is the most common call we get all summer in Stuart. $120-160 fix.
A weak start capacitor can't give the compressor enough boost, so it draws excessive amps trying to start under its own power. In 95+ degree heat the compressor is already under load. A hard start kit solves this about 70% of the time. If the compressor itself is drawing too many amps even with a new cap, we'll let you know honestly.
Short cycling from a run capacitor that's lost too many microfarads. The compressor starts okay but can't sustain operation because the cap isn't providing enough ongoing boost. We test the cap with a digital meter - if it reads more than 5% below its rated value, it's done. New cap fixes this immediately.
That's a dead giveaway. When a capacitor overheats, the electrolyte inside expands and bulges the can. Sometimes you'll see oil leaking from the top. Don't try to discharge it yourself - a charged cap can deliver a serious shock even with the power off. We handle the safe removal and replacement.
A capacitor on its last legs will work when temps are moderate but fail when it gets really hot. As the rooftop shroud temperature climbs past 120 degrees, the weak cap can't perform. This is the sneakiest symptom because it makes you think it's a refrigerant issue. We test the cap under load to catch this.
Recurring capacitor failure usually means something else is wrong - a compressor with bad windings, a contactor that's welding shut, or an electrical supply issue. We don't just swap the cap and leave. We check amp draw, contactor condition, and wiring to make sure the new cap will last.
Getting the wrong microfarad value will either not work or burn out fast. Here's what we commonly replace across the brands we service in Stuart and Martin County.
Dometic rooftop units typically use a 35/5 MFD dual run capacitor for the compressor and fan motor circuits. The Brisk II 13,500 BTU is the most common unit in the field. We carry the exact Dometic replacement values on the truck. When these caps fail in Florida heat, the compressor hums but won't engage. We probably replace 4-5 of these every week during summer in Stuart alone.
Coleman-Mach units (made by Airxcel) use slightly different capacitor configurations than Dometic. The Mach 8 typically runs a 30/5 MFD dual cap, while the Mach 15 uses a 45/5 MFD. Getting the right microfarad value matters. We've seen DIYers put a 35 MFD cap on a Coleman that needs a 45, and the compressor can't sustain operation. We match it exactly every time.
A hard start kit like the Supco SPP6 or RCO410 adds a relay-activated start capacitor boost that drops out after startup. It works on Dometic, Coleman, Advent, and Furrion units. We install these as a preventive upgrade on units over 5 years old, or as a fix when the compressor is struggling to start in extreme heat but isn't actually failing yet. It's the best $130-200 investment for an aging AC.
Advent Air units use standard round-can capacitors but at lower price points. Furrion Chill units are newer to the market and use a different board layout. Both brands are straightforward to service once you know the specs. We keep common values for these on the truck and can source oddball specs from our local suppliers in Stuart within 24 hours if needed.
Call 772-280-3915 or request a quote. Common symptoms: AC hums but won't start, trips breaker, compressor clicks then shuts off. If you know the brand, let us know so we can confirm we've got the right cap on the truck. Same or next day scheduling across Stuart.
Our tech pulls the rooftop shroud, safely discharges the capacitor, and tests microfarad readings with a digital meter. A healthy cap reads within 5% of its rated value. Anything below that means it's failing. We test both start and run capacitors, plus check compressor amp draw to rule out other issues.
We carry the most common RV AC capacitor values on the truck. The swap takes 15-20 minutes. After installation, we verify compressor amp draw to confirm the new cap is performing correctly. The whole visit is usually done in under an hour. You're back to cold air fast.
| Repair Type | Price Range | Typical Time |
|---|---|---|
| Run capacitor replacement | $120-160 | 15-20 min |
| Start capacitor replacement | $140-200 | 20 min |
| Dual capacitor replacement | $150-220 | 20-30 min |
| Hard start kit installation | $130-200 | 20-30 min |
| Capacitor + hard start combo | $200-250 | 30-40 min |
| Fan motor capacitor | $100-140 | 15 min |
| Full AC diagnostic (if cap isn't the issue) | $80-120 | 30-45 min |



AC was just humming but no cold air. Dealer wanted to bring the whole rig in for a $400 diagnostic. Stuart RV Repair came out, tested the capacitor with a meter, showed me the readings, and had a new one in within 20 minutes. Total cost was $145. Best money I've spent.
Kept tripping our breaker at the campground. Tech put a hard start kit on and also found the run cap was weak. Replaced both for around $220. AC hasn't tripped a breaker since. That was three months ago and we're in the middle of Florida summer.
I tried replacing the capacitor myself and put the wrong value in. AC worked for two days then the new cap blew. The tech from Stuart RV Repair explained exactly why, put the correct one in, and now it's running great. Lesson learned - call the pro first.
An RV AC capacitor replacement in Stuart runs $120-220 including the part and labor. A run capacitor swap is on the lower end at $120-160. A start capacitor or dual capacitor costs a bit more at $150-220. Hard start kit installation runs $130-200. We give you an exact quote on-site before starting.
The telltale signs are: the AC hums but the compressor won't kick on, the unit trips the breaker every time it tries to start, the compressor starts then shuts off after a few seconds, or the AC blows warm air even though the fan runs. A swollen or leaking capacitor is a dead giveaway. We test with a digital meter to confirm.
A start capacitor gives the compressor an extra electrical boost during startup, then drops out of the circuit. A run capacitor stays in the circuit the whole time the compressor operates, helping maintain consistent power. Most RV rooftop ACs have a run capacitor. Some also have a separate start capacitor or a dual cap that combines both.
A hard start kit adds extra starting torque to your compressor via a relay-activated capacitor boost. You probably need one if your AC trips the breaker on startup, struggles to start in extreme heat, or if your compressor is over 5-6 years old. We install these as preventive upgrades on a lot of RVs in Stuart. Runs $130-200 installed.
Heat is the #1 killer. Florida summers push rooftop shroud temperatures above 140 degrees. Capacitors are rated for a certain number of cycles at a given temperature. Every degree above the rated temp shortens the cap's life. A cap rated for 10 years up north might last 3-4 years in Martin County. We replace more capacitors between May and October than any other AC part.
You technically can, but capacitors store a lethal electrical charge even when the power is off. If you don't discharge it properly, you can get a serious shock. You also need to match the exact microfarad rating and voltage. Getting the wrong value will either not work or burn out fast. For $120-160 all-in, it's worth having a tech handle it safely.
We handle all RV A/C and heating repairs - rooftop units, capacitors, furnaces, thermostats, and ductwork. If you've got multiple climate control issues, we bundle them into one visit across Stuart and the Treasure Coast.
We cover Martin, St. Lucie, and Palm Beach counties for all RV AC capacitor work. From Stuart and Palm City to Jensen Beach, Hobe Sound, and down to Jupiter.
It's probably a capacitor. Call us or request a free estimate. We carry the most common caps on the truck and can usually have you back to cold air in under an hour. Same-day mobile service across the Treasure Coast.