Comfort Systems USA Hits Record $782 On Thin Volume Despite Overbought Signals

Comfort Systems USA (FIX) advanced 3.76% to close at $782.05 on September 15, 2025, establishing a new high within the session range of $755–$782.46. This movement occurred on below-average volume of 396,716 shares, suggesting potential fatigue near all-time highs despite the strong price performance. We assess key technical dynamics through multiple lenses below.
Candlestick Theory
Recent sessions show a bullish engulfing pattern formed on September 10–11, where a large green candle ($721.87–$752.10) swallowed the prior red candle’s body ($709.53–$717.50), confirming demand at interim support. The September 15 candle closed near its high after testing $755 support, reinforcing this level as immediate downside protection. Critical resistance resides at $782.46 (intraday high), while breach of $755 may trigger profit-taking toward stronger support near $721.87 (September 10 low).
Moving Average Theory
The 50-day SMA (~650), 100-day SMA (~550), and 200-day SMA (~450) maintain bullish sequencing—shorter averages above longer ones—confirming an entrenched uptrend. Price remains firmly above all three, with the 50-day SMA acting as dynamic support during August and September pullbacks. No death crosses (bearish SMA crossovers) are evident, supporting the primary bullish structure. The expanding gap between price and the 200-day SMA underscores strong momentum but may warrant monitoring for stretched valuations.
MACD & KDJ Indicators
The MACD (12/26/9) sustains a positive histogram since mid-July, signaling sustained bullish momentum, though its slope flattened in early September during consolidation. Concurrently, the KDJ oscillator (9-day) shows %K at >90 and %D above 80, reflecting extreme overbought conditions. While MACD supports trend continuation, KDJ’s overextension signals mounting risk of a tactical pullback. No bearish divergence is yet observed, but further price gains without KDJ reset could precipitate profit-taking.
Bollinger Bands
Price consistently hugs the upper Bollinger Band (20-day SMA + 2σ) since July, denoting strong directional bias. Recent band expansion aligns with September’s volatility spike, but the latest approach to $782.46 coincides with the upper band, implying technical resistance. Mean reversion toward the 20-day SMA (~720) would be consistent with typical volatility cycles, though sustained upper-band proximity favors upside continuation while volatility remains elevated.
Volume-Price Relationship
Volume surges validated key rallies: July 25 (1.25M shares, +22.37%), September 10 (616K shares, +6.00%), and August 12 (379K shares, +3.65%). However, the September 15 breakout occurred on below-average volume (-35% vs. 10-day mean), suggesting limited conviction at new highs. This volume divergence flags caution despite the closing gain. Downside confirmation would require expansion on breaks below $755 support.
Relative Strength Index (RSI)
The 14-day RSI (66.5) cooled from overbought territory (>70) after mid-August but rebounded to 68.0—approaching cautionary levels. While not yet overbought, its proximity to 70 alongside KDJ’s overextension implies limited near-term upside runway. Should RSI exceed 70 on sustained volume, momentum could extend, but historically such conditions preceded minor consolidations (e.g., early July pullback from RSI 75).
Fibonacci Retracement
Using the swing low of $340.41 (September 16, 2024) and high of $782.46 (September 15, 2025), key retracement supports emerge at $678.14 (23.6%), $613.60 (38.2%), and $561.44 (50%). These align with technical support near the 50-day SMA ($650) and the July breakout point ($560). The $678–$650 zone represents a high-confluence area for buyers, combining Fibonacci, SMA, and prior consolidation support.
Confluence & Divergences
Confluence appears at $720–$680, where Fibonacci (23.6%), moving averages (50-day SMA), volume-supported former resistance (July/August highs), and Bollinger mid-band converge, offering robust support. Bearish divergence manifests via KDJ overbought signals and low volume at new highs, contrasting with MACD’s resilience. While structural trends remain intact, tactical indicators suggest a digestion phase near $782.46 resistance may precede further gains. A decisive close above $782.46 with volume expansion would invalidate near-term bearish divergences.